RELATED APPLICATIONS

[0001] This application claims the benefits of priority under 35 U.S.C. 119 (e) to U.S. Provisional Patent Application Serial No. 61/432,794, filed on January 14, 2011.

FIELD

[0002] The present disclosure relates to effecting reactions in a plasma. BACKGROUND

[0003] Plasma based reactions for effecting reformation of natural gas are known. However, existing methods operate with less than desirable conversion efficiencies and are plagued with issues of carbon deposition.

SUMMARY

[0004] In one aspect, there is provided method of operating a plasma reactor including a reaction zone. The method includes generating a plasma in the reaction zone, and contacting reactant matter with the plasma in the reaction zone, wherein the pressure in the reaction zone is at least 75 psig.

[0005] In another aspect, there is provided a reactor, defining an internal space including a reaction zone, and includes a plasma generator. The plasma generator includes first and second electrodes. The first electrode is configured for electrical coupling to a current and voltage source. The second electrode is spaced apart from and disposed in electrical discharge communication with the first electrode through the internal space, and includes an operative second electrode surface portion. The reaction zone is disposed between the first and second electrodes. When a plasma forming gaseous fluid is disposed within the reaction zone and a sufficient electrical potential difference is applied between the first electrode and the operative second electrode surface portion, an electrical discharge is effected between the first electrode and the operative second electrode surface portion and through the reaction zone, and at least a fraction of the plasma forming gaseous fluid is converted into a plasma. The operative second electrode surface portion is defined by a radius of curvature of less than 0.002 inches.

[0006] In another aspect, there is provided a reactor including an internal surface defining an internal space including a reaction zone. The reactor includes a plasma generator. The plasma generator includes first and second electrodes. The first electrode is configured for electrical coupling to a current and voltage source. The second electrode is spaced apart from and disposed in electrical discharge communication with the first electrode through the internal space, and includes an operative second electrode surface portion. The reaction zone is disposed between the first electrode and the operative second electrode surface portion. When a plasma forming gaseous fluid is disposed within the reaction zone and a sufficient electrical potential difference is applied between the first electrode and the operative second electrode surface portion, an electrical discharge is effected between the first electrode and the operative second electrode surface portion and through the reaction zone, and at least a fraction of the plasma forming gaseous fluid is converted into a plasma. The first electrode is mounted within a reaction vessel with a mounting structure including an internal mounting structure surface defining a portion of the internal surface, wherein the mounting surface is disposed in fluid communication with the reaction zone. The minimum distance between the operative second electrode surface and the mounting structure is at least two (2) inches.

[0007] In another aspect, there is provided a reactor, defining a fluid passage portion for flowing a plasma forming gaseous fluid, wherein the fluid passage portion includes an upstream fluid passage portion and a downstream fluid passage portion. The reactor includes a plasma generator. The plasma generator includes first and second electrodes. The first electrode is configured for electrical coupling to a current and voltage source. The second electrode is spaced apart from and disposed in electrical discharge communication with the first electrode through the internal space, and includes an operative second electrode surface portion. The reaction zone is defined between the first electrode and the operative second electrode portion, and the downstream fluid portion extends downstream from within the reaction zone. When the plasma forming gaseous fluid is disposed in the reaction zone and a sufficient electrical potential difference is applied between the first electrode and the operative second electrode surface portion, an electrical discharge is effected between the first electrode and the operative second electrode surface portion and through the reaction zone, and at least a fraction of the plasma forming gaseous fluid is converted into a plasma. The operative second electrode surface portion is spaced apart from the first electrode by a minimum distance of less than 0.15 inches. The upstream fluid passage portion is defined by an upstream conduit wall disposed upstream of the reaction zone, wherein the upstream conduit wall includes at least one electrically conductive upstream conduit wall portion. Any electrically conductive upstream conduit wall portion, which is disposed in electrical discharge communication with the first electrode, is disposed further from the first electrode than the operative second electrode surface portion. The operative second electrode surface portion is disposed in thermal communication with at least one electrically conductive upstream conduit wall portion.

[0008] In another aspect, there is provided, a reactor, defining a fluid passage portion for flowing a plasma forming gaseous fluid, wherein the fluid passage portion includes an upstream fluid passage portion and a downstream fluid passage portion. The reactor includes a plasma generator. The plasma generator includes first and second electrodes. The first electrode is configured for electrical coupling to a current and voltage source. The second electrode is spaced apart from and disposed in electrical discharge communication with the first electrode through the internal space. The reaction zone is defined between the first electrode and the second electrode, and the downstream fluid passage portion extends downstream from within the reaction zone, and the upstream fluid passage portion is disposed upstream of the reaction zone. When the plasma forming gaseous fluid is disposed within the reaction zone and a sufficient electrical potential difference is applied between the first electrode and the second electrode, an electrical discharge is effected between the first electrode and the second electrode and through the reaction zone, and at least a fraction of the plasma forming gaseous fluid is converted into a plasma. The first electrode is at least partially disposed in the downstream fluid passage portion and is spaced apart from an internal conduit wall of the downstream fluid passage portion to define a fluid flow space in the downstream fluid passage portion, wherein, in any plane which intersects that portion of the first electrode disposed in the downstream fluid passage portion, and which is disposed in a normal orientation relative to an axis of the downstream fluid passage portion being intersected, the ratio of the diameter of the first electrode to the diameter of the downstream fluid passage portion is between two (2) and five (5).

[0009] In another aspect, there is provided a reactor, including an internal space defining a fluid passage portion for flowing a plasma forming gaseous fluid, wherein the fluid passage portion includes a reaction zone. The reactor includes a plasma generator. The plasma generator includes first and second electrodes. The first electrode is configured for electrical coupling to a current and voltage source, and including an operative first electrode surface portion. The second electrode is spaced apart from and disposed in electrical discharge communication with the first electrode through the internal space, and including an operative second electrode surface portion. The reaction zone is disposed between the first and second electrodes. When a plasma forming gaseous fluid is disposed within the reaction zone and a sufficient electrical potential difference is applied between the operative first electrode surface portion and the operative second electrode surface portion, an electrical discharge is effected between the operative first electrode surface portion and the operative second electrode surface portion and through the reaction zone, and at least a fraction of the plasma forming gaseous fluid is converted into a plasma. An operative distance is defined along the longitudinal axis of the first electrode between: (i) a plane in which is disposed an axis normal to the operative first electrode surface portion and (ii) a tip of the first electrode downstream of the operative first electrode surface portion, wherein the operative distance is at least 0.25 inches.

[0010] In another aspect, there is provided a reactor, defining an internal space including a reaction zone, and including an inlet fluidly coupled to the reaction zone with a fluid introduction passage for introducing a plasma forming gaseous fluid into the reaction zone. The reactor includes a plasma generator. The plasma generator includes first and second electrodes. The first electrode is configured for electrical coupling to a current and voltage source. The second electrode is spaced apart from and disposed in electrical discharge communication with the first electrode through the internal space. The reaction zone is disposed between the first and second electrodes. When a plasma forming gaseous fluid is disposed within the reaction zone and a sufficient electrical potential difference is applied between the first electrode and the second electrode, an electrical discharge is effected between the first electrode and the second electrode and through the reaction zone, and at least a fraction of the plasma forming gaseous fluid is converted into a plasma. The reaction vessel includes a heat exchanger disposed in heat transfer communication with the fluid introduction passage for effecting heat transfer to plasma forming gaseous fluid being introduced to the reaction zone.

BRIEF DESCRIPTION OF THE DRAWINGS

[0011] The apparatus and method of the preferred embodiments of the invention will now be described with the following accompanying drawings:

[0012] Figure 1 is a schematic illustration of an embodiment of an electric circuit for effecting a high voltage power supply to a reactor;

[0013] Figure 2 is a schematic illustration of a sectional, front elevation view of an embodiment of the reactor;

[0014] Figure 3A is an exploded sectional view of the high voltage feedthrough assembly of the reactor in Figure 1 ;

[0015] Figure 3B is an exploded sectional view of a lower portion of the reactor in Figure 2;

[0016] Figure 4 is a sectional detailed front elevation fragmentary view of an upper portion of the reactor in Figure 2;

[0017] Figure 5 is a sectional detailed front elevation fragmentary view of a lower portion of the reactor in Figure 2; [0018] Figure 6 is a sectional detailed front elevation exploded view of the lower portion of the reactor in Figure 2;

[0019] Figure 7 is a schematic illustration of a sectional, front elevation view of another embodiment of the reactor;

[0020] Figure 8 is the same view as in Figure 2, and illustrates the dimension Dl , which is the minimum distance between the operative second electrode surface portion and the mounting surface within the reactor.

[0021] Figure 9 is a sectional detailed front elevation fragmentary view of a lower portion of the reactor in Figure 2, and illustrates the dimension D2, which is the minimum distance by which the operative second electrode surface portion is spaced apart from the first electrode within the reactor.

[0022] Figures 10 and 11 illustrate the relationship between dimensions D3, which is the diameter of the first electrode, and D4, which is the diameter of the downstream fluid passage portion, wherein Figure 10 is the same view as in Figure 5 and also illustrates generated plasma, and Figure 11 is a cross-sectional view of the downstream fluid passage portion taken along plane 200; and

[0023] Figure 12 is the same view as in Figure 5 and also illustrates generated plasma, and also illustrates the dimension D5, which is an operative distance defined along the longitudinal axis of the first electrode between: (i) a plane in which is disposed an axis normal to the operative first electrode surface portion, and (ii) the tip of the first electrode.

DETAILED DESCRIPTION

[0024] Referring to Figures 1 to 12, there is provided a reactor 10 configured for generating a plasma.

[0025] Referring to Figure 2, the reactor 10 includes an internal space 26 including a reaction zone 32. The reactor 10 also includes a plasma generator 34. The plasma generator 34 includes a first electrode 36 and a second electrode 52. The first electrode 36 is configured for electrical coupling to a current and voltage source 44. The second electrode 52 is spaced apart from and disposed in electrical discharge communication with the first electrode 36 through the internal space 26. In some embodiments, for example, the second electrode 52 is a ground electrode. The reaction zone 32 is disposed between the first electrode 36 and the second electrode 52. When the plasma forming gaseous fluid is disposed within the reaction zone 32 and a sufficient electrical potential difference is applied between the first electrode 36 and the second electrode 52, an electrical discharge is effected between the first electrode 36 and the second electrode 52 and through the reaction zone 32, and at least a fraction of the plasma forming gaseous fluid is converted into a plasma.

[0026] In some embodiments, the internal space 26 includes a fluid passage portion 64 for flowing a plasma forming gaseous fluid through the reaction zone 32. For example, in some embodiments, the fluid passage portion 64 includes an upstream fluid passage portion 66 disposed upstream of the reaction zone 32, and also includes a downstream fluid passage portion 74 extending downstream from within the reaction zone 32.

[0027] With respect to the second electrode 52, in some embodiments, for example, the second electrode 52 includes an operative second electrode surface portion 54. When the plasma forming gaseous fluid is disposed within the reaction zone 32 and a sufficient electrical potential difference is applied between the first electrode 36 and the operative second electrode surface portion 54, the effected electrical discharge is between the first electrode 36 surface and the operative second electrode surface portion 54 and at least a fraction of the plasma forming gaseous fluid is converted into a plasma. In this respect, in some embodiments, for example, the reaction zone 32 is provided in an internal space 26 defined by an internal surface 28 of the reactor 10, and the operative second electrode surface portion 54 is an electrically conductive surface portion of the internal surface 28 that is closest to the first electrode 36.

[0028] In some embodiments, the reactor 10 includes a reaction vessel 12, and the first electrode 36 is mounted within the reaction vessel 12 with a mounting structure 46. In some embodiments, for example, the reaction vessel is constructed of stainless (such as 304 stainless steel, or 316 stainless steel). In some embodiments, for example, standard pipe flange connections are provided to effect coupling to feed and exhaust systems.

[0029] In some embodiments, the first electrode 36 is electrically coupled to the current and voltage source 44. For example, with respect to the current and voltage source 44, the frequency of the current and voltage source 44 is from lOKHz to 20KHz, and the pulse width of the current and voltage source 44 is from 10 to 20 micro-seconds. An exemplary electrical circuit for effecting a high voltage power supply to the first and second electrodes 36, 52 is illustrated in Figure 1. The first electrode 36 is electrically connected to a power supply. The power supply 2011 includes a rectifier 2013, a pulser 2015 (or inverter), a high voltage pulse transformer 2017, and, optionally, high voltage capacitors 2019 connected in series with the secondary winding of the pulse transformer 2017. The high voltage capacitors 2019 function in multi-discharge generation and for impedance matching, and, in this respect, allow simultaneous powering of multiple electrodes by a single power source, such as various embodiments of the reactor 10 which are described and illustrated in Canadian Patent Application No. 2,516,499 which is herein incorporated by reference in its entirety. The high voltage capacitors 2019 can be omitted under single discharge conditions. The power supply provides controlled bipolar high voltage pulses to a high voltage transformer which acts as a filter to make the current almost sinusoidal. For example, switching frequencies are between 10 kHz to 20 kHz, such as between 15 kHz to 17 kHz. For example, the pulse widths are between 10 to 20 microseconds, such as between 15 to 17 microseconds. For example, in operation, a stable flow of plasma forming gaseous fluid is established through the reactor vessel, and once substantially all of the ambient air has been purged from the reaction vessel 12, a high voltage pulse is supplied to the first electrode 36, and plasma is created in the reaction zone 32 between the first electrode 36 and the second electrode 52.

[0030] For example, with respect to the first electrode 36 and the second electrode 52, each one of these electrodes is electrically conductive and is configured to operate robustly in high temperature conditions. [0031] For example, with respect to the first electrode 36, the first electrode 36 includes a lanthanated tungsten rod. Other examples of suitable materials for the first electrode 36 structure include substantially pure tungsten, 2% thoriated tungsten, tungsten carbide, and other tungsten alloys.

[0032] Referring to Figures 2, 3A, and 4, in some embodiments, for example, the first electrode 36 is electrically coupled to the voltage and power source through a high voltage feedthrough assembly 300. The high voltage feedthrough assembly (HVFA) 300 is configured to provide high voltage (HV) power to the first electrode 36 and to contain any pressurized gas within the reaction vessel 12. The HVFA 300 is configured to operate continuously at 20 kV and 20 kHz and at a working pressure of 300psig. A set of releasably coupled flanges 302, 121 provide for access to the HVFA.

[0033] In some embodiments, the HVFA 300 is composed of a top flange 302, an insulator 304, a high voltage input conductor 306, a threaded insert 308, a high voltage conductor holder 310, and an alignment ring 312. The HVFA defines an upper reaction vessel portion 1202 of the reaction vessel 12.

[0034] The top flange 302 is provided for holding the HVFA 300 while simultaneously ensuring a hermetic seal for the reaction vessel 12. The top flange 302 maintains the integrity of coupling between the HVFA 300 and the remaining portion of the reaction vessel 12 when pressurized gas is provided within the reaction vessel 12.

[0035] The insulator 304 provides electrical insulation between the metallic high voltage and grounding components of the reactor 10 and contains the pressure inside the reaction vessel 12. For example, the material of the insulator 304 is MACOR™ made by Corning Incorporated. The insulator carries two (2) o-ring seals 314, 316 that provide a positive seal with the top flange 302. The high voltage feed conductor 306 extends through a passage provided through the center of the insulator 304.

[0036] The high voltage input conductor 306 is electrically coupled to the first electrode 36 and is provided for conducting high voltage power to the first electrode 36. The high voltage input conductor 306 also provides a pressure barrier to gas pressure within the reaction vessel 12. There are two (2) o-rings 318, 320 carried by the larger, middle section of the high voltage input conductor 306. The high voltage input conductor 306 is made from stainless steel but can be made from any conductive metal that is compatible with the fluid used and that is rated for the operating pressure. The first electrode 36 is attached to the high input conductor 306 by friction fit within a hole 322 provided in the high voltage input conductor 306. The hole 322 is sized slightly smaller than the first electrode 36 and is drilled inside the high voltage input conductor 306. Slits are formed on the side to allow the wall to expand slightly, when the first electrode 36 is inserted.

[0037] The high voltage input conductor 306 is coupled to the insulator 304 by the threaded insert 308. In some embodiments, for example, the threaded insert 308 is manufactured from Teflon™ made by E. I. du Pont de Nemours and Company.

[0038] The high voltage conductor holder 310 maintains positioning of the high voltage input conductor 306 at the center of the assembly 300 and includes a passage through which the high voltage input conductor 306 extends. The holder 310 also provides electrical insulation between the high voltage input conductor 306 and the internal surface 28 of reaction vessel 12. In some embodiments, for example, the high voltage conductor holder 310 is made from Teflon™. The high voltage conductor holder 310 is supported by the alignment ring 312.

[0039] The alignment ring 312 supports the high voltage conductor holder 310 and provides a seal between the flanges 302, 121 . In some embodiments, for example, the alignment ring 312 is made from stainless steel.

[0040] Assembly of an embodiment of the reactor 10 will now be described. The reactor includes the upper reaction vessel portion 122, an intermediate reaction vessel portion 124, and a lower reaction vessel portion 126.

[0041] The intermediate reaction vessel portion 124 includes a second electrode assembly 1244 coupled to and disposed internally within an intermediate containment component 1242. The second electrode assembly 1244 includes a second electrode- comprising structure 1246 (for example, made from tungsten), a containment structure

1248 (for example, made from stainless steel), an upper sleeve 1250 (for example, made from tungsten), a lower sleeve 1252 (for example, made from tungsten), a heat transfer medium 94 (for example, steel wool), and an insulator 1254 (for example, made from MACOR™. The second electrode— comprising structure includes the second electrode 52. The combination of the upper and lower sleeves 1250, 1252 define at least a portion of the downstream fluid passage portion extending from the within the reaction zone 32. The heat transfer medium 94 is provided to effect dissipation of heat from an internal surface portion 96, of a downstream internal conduit surface 76, adjacent to the reaction zone 32. The insulator 1254 is disposed downstream of the heat transfer medium 94, and is provided for mitigating heat transfer from a downstream fluid passage portion 74 so as to assist in sustaining reactive processes within the plasma, as described below.

[0042] The assembly of the second electrode assembly 1244 is now described. The upper sleeve 1250 is seated on a seating surface provided on the lower sleeve (see Detail "A" in Figure 6). The second electrode-comprising structure 1246 is then seated on the upper sleeve 1250, and this intermediate assembly is then inserted into a receiving space

1249 defined within the containment structure 1248 to provide a second intermediate assembly, such that the second-electrode comprising structure 1246 is seated on the containment structure 1248. A set screw is inserted through passage 1266 and tightened against the lower sleeve 1252 to effect desired positioning of the lower sleeve 1252 relative to the containment structure 1248. The second electrode-comprising structure 1246 is then removed from the second intermediate assembly, and the insulator 1254 is inserted into space provided between the containment structure 1248 and the lower sleeve 1252, such that sufficient space remains for receiving the heat transfer medium 94 between the sleeves 1250, 1252 and the containment structure 1248. The heat transfer medium 94 is then inserted into this remaining space in a well-packed condition. The second electrode-comprising structure 1246 is then returned, and positioned such that the second electrode-comprising structure 1246 is seated on the upper sleeve 1250, the heat transfer medium 94, and the containment structure 1248. A set screw is inserted through passage 1264 and then tightened against the second electrode-comprising structure to effect its desired positioning relative to the containment structure 1248. [0043] The second electrode assembly 1244 is then inserted into a receiving space 1257 defined within the intermediate containment component 1242, and threadably coupled to the intermediate containment component 1242 by co-operative threads 1260, 1262 (see Figure 3B) provided on the second electrode assembly 1244 and the intermediate containment component 1242, respectively. Positioning of the second electrode assembly 1244, and, therefore, the second electrode 52 and the operative second electrode portion 54, is adjusted by rotating the second electrode assembly 1244 relative to the intermediate containment component 1242 while the second electrode assembly 1244 is threadably engaged to the intermediate containment component 1242.

[0044] The upper reaction vessel portion 122, defined by the HVFA 300, is integrated into the reactor 10 by coupling to the assembled intermediate reaction vessel portion 124. The insulator/pressure barrier 304 with its two (2) o-rings 314, 316 in place is inserted from below into the upper reaction vessel portion flange 302, making sure it is firmly in contact with the flange 302. The high voltage input conductor 306, with its two (2) o-rings installed 318, 320, is inserted through the passage provided in the insulator/pressure barrier 304. The larger diameter section of the high voltage input conductor 306 is firmly seated against the insulator/pressure barrier 304. The threaded insert 308 is screwed into the insulator/pressure barrier 304 to hold the high voltage input conductor 306 in place. The high voltage conductor holder 310 is then inserted into the alignment ring and this assembly is inserted through the top of and into the flanged lower reaction vessel portion 13. The flange 302 is coupled to a intermediate reaction vessel portion upper flange 121 of the intermediate containment component 1242, with the alignment ring 312 disposed in-between the two flanges 302, 121. Bolts and nuts are inserted in each flange hole and tightened appropriately to effect coupling of the HVFA 300 to the intermediate containment component 1242.

[0045] The lower reaction vessel portion 126 is then coupled to the intermediate reaction vessel portion 124. The lower reaction vessel portion 126 includes the outlet 22. A lower reaction vessel portion flange 1261 of the lower reaction vessel portion 126 is connected to an intermediate reaction vessel portion lower flange 1256 using bolts and nuts. [0046] For example, with respect to the second electrode 52, the second electrode 52 is made from stainless steel. Other examples of suitable materials include lanthanated tungsten, substantially pure tungsten, 2% thoriated tungsten, tungsten carbide, other tungsten alloys, graphite, or silicon carbide.

[0047] For example, with respect to the plasma forming gaseous fluid, the plasma forming gaseous fluid is any one of those fluids that can be ionized through electron impact events within a voltage potential gradient, and thereby create a reduced impedance pathway that provides a current path. Any ionisable fluid can form a plasma provided that a sufficient electric potential gradient exists. Such ionisable fluids include, but are not limited to, elemental species such as the noble gases (He, Ne, Ar, etc.), molecular gases (i.e. H ₂ , 0 ₂ , 0 ₃ , CH ₄ , CF ₄ , SF ₆ , H ₂ S, etc.) and vaporizable organic liquids (i.e. butane, hexane), organometallic liquids (i.e. tetaethoxysilane, trimethylphosphine, etc) and inorganic liquids (water, TiCl ₄ ). For example, the plasma forming gaseous fluid includes no gaseous oxygen or substantially no gaseous oxygen.

[0048] For example, with respect to the reactor 10, the reactor 10 includes an inlet 20 configured for introducing the plasma forming gaseous fluid flow to the plasma generator 34 so as to effect the plasma discharge into the reaction zone 32 by the plasma generator 34 such that the plasma discharge facilitates conversion of reactant matter in the reaction zone 32 into product matter.

[0049] As a further example with respect to the reactor 10, the reactor 10 is configured for receiving reactant matter within the reaction zone 32. For example, the reactant matter is in the form of a fluid, such as a gaseous fluid, and the reactor includes the inlet 20 for introducing reactant matter fluid as reactant matter fluid flow into the reaction zone 32. In the illustrated embodiment, the inlet 20 for the plasma forming gaseous fluid flow is the same as the inlet 20 for the reactant matter fluid flow as the plasma forming gaseous fluid is the same as the reactant matter fluid. For example, the plasma forming gaseous fluid flow, when it is the same as the reactant matter fluid flow, is introduced through the inlet 20 at a flow rate of 3.5 cubic metres per hour. [0050] For example, with respect to the reactant matter, the reactant matter consists of any one of: (i) an element, (ii) a compound, (iii) a homogeneous or inhomogeneous mixture of any one of: (a) at least two elements, or (b) at least two compounds, or (iv) a homogeneous or inhomogeneous mixture of any combination of: (a) at least one element, and (b) at least one compound.

[0051] As a further example, with respect to the reactant matter, the reactant matter, which is suitable for conversion within the plasma generated by the plasma generator 34 includes gaseous and liquid hydrocarbons such as natural gas, volatile petroleum fractions, landfill and other bio-generated fuel gases, methane, ethane, propane, propene, butane, pentane, and hexane, and volatile oxygenated organic compounds such as methanol, and ethanol, and reactive molecular element species such as, but not limited to, hydrogen, oxygen and ozone, and volatile inorganic hydrides such as, but not limited to, H ₂ S, SiH ₄ , PH ₃ , and As¾. In some embodiments, for example, the reactant matter includes syngas (carbon dioxide and methane). At least a fraction of the reactant matter is subjected to a reactive process in the plasma generated by the plasma generator 34, such that the reactive process effects creation of product matter.

[0052] For example, with respect to the product matter, the product matter includes solid particulate matter. For example, the solid particulate matter includes carbon- comprising matter, such as carbon. For example, with respect to the solid particulate matter of the product matter, at least a fraction of the solid particulate matter of the product matter becomes coupled to an internal surface 28 of the reaction vessel 12. The solid particulate matter is said to be coupled to the internal surface 28 when the solid particulate matter adheres to the internal surface 28 or becomes associated with solid matter which is already adhered to the internal surface 28. Mechanisms for association of the solid particulate matter with the solid matter adhered to the internal surface 28 include absorption, dissolution, covalent bonding, or ionic bonding. The operative forces, whose action effects the adhesion or the association, include any one of, or any combination of, Van der Waals adhesive forces, electrostatic forces, and gravity. [0053] For example, with respect to the plasma forming gaseous fluid, the plasma forming gaseous fluid includes the reactant matter. In this respect, for example, the plasma forming gaseous fluid includes any of the suitable reactant matter described above.

[0054] As a further example, with respect to the plasma forming gaseous fluid including the reactant matter, a suitable plasma forming gaseous fluid is natural gas, typically including 70 mole % to 95 mole % methane, based on the total number of moles of plasma forming gaseous fluid, with small amounts of other hydrocarbons such as ethane and propane and varying levels of inert gases such as nitrogen and contaminant gases such as hydrogen sulphide. For example, these fluids are introduced into the plasma reactor 10 at flows that can vary between very low (lO's of cc/min) to very high (lO's of Nm /hour). The plasma forming gaseous fluid is provided within the reaction zone 32. For example, natural gas feed flow to the reactor 10 ranges between 0.1 Nm /hour and 10 Nm ³ /hour. For example, the reaction is carried out at pressures that may range from medium vacuum (100's of Torr) to atmospheric and relatively high pressures (i.e. up to at least 300 psig). In this respect, for example, the reaction is carried out at a pressure of 150 psig. For example, once the plasma has been initiated, the system temperature is allowed to equilibrate to accommodate the small zone of very high (1000-1500°C) temperature in the plasma plume. For example, internal wall temperatures of the reactor 10 may be as high as 500°C. Depending on the reactant matter, the reactant matter of the plasma forming gaseous fluid is converted in the reaction zone 32 in accordance with any one of or any combination of the reaction steps described in Appendix "A".

[0055] In this respect, the conversion of the reactant matter of the plasma forming gaseous fluid results in product matter including solid particulate matter, wherein the solid particulate matter includes carbon.

[0056] In some embodiments, for example, the reactor 10 includes an outlet 22 configured for discharging the product matter. In some embodiments, the reaction vessel 12 also includes a heat exchanger disposed in thermal communication with the outlet 22 and configured for effecting heat transfer from the product matter discharging through the outlet 22. Such heat transfer effects cooling of the discharging product matter. For example, such heat transfer could effect heating of the plasma forming gaseous fluid before the plasma- forming gaseous fluid is introduced into the reaction vessel 12. In this respect, the heat exchanger is configured to receive the plasma-forming gaseous fluid and effect heat transfer from the discharging product matter and to the plasma-forming gaseous fluid.

[0057] Referring to Figure 10, in some embodiments, for example, an internal surface portion 96, of a downstream internal conduit surface 76, adjacent to the reaction zone 32, is disposed in thermal communication with a heat transfer medium 94 extending between the reaction zone adjacent internal surface portion 96 and an external surface 98 of the reactor for effecting dissipation of heat from the internal surface portion 96. In some embodiments, for example, the heat transfer medium 94 is steel wool.

(A) OPERATING AT HIGHER PRESSURES

[0058] One aspect is associated with a method of operating a plasma reactor 10. The plasma reactor 10 includes a reaction zone 32. The method includes contacting reactant matter with a plasma 102 in a reaction zone 32. For example, the plasma 102 is generated in the reaction zone 32. The pressure in the reaction zone 32 is at least 75 psig. In some embodiments, for example, the pressure in the reaction zone 32 is greater than 300 psig. In other embodiments, for example, the pressure in the reaction zone 32 is 150 psig. By providing the above-described pressure in the reaction zone 32, and amongst other things, there is effected a greater residence time for the reactant matter in the reaction zone 32, which effects a greater conversion of reactant matter into gaseous hydrogen and effects reduction in the amount of polycyclic aromatic hydrocarbons (PAH) associated with the solid particulate matter.

[0059] In some embodiments, the plasma 102 (see Figures 10 or 12) is generated by flowing a plasma forming fluid flow through a reaction zone 32 through which an electrical discharge is being effected. In some embodiments, the plasma forming fluid includes reactant matter. In some embodiments, the reactant matter includes natural gas. For example, the reactant matter includes methane. (B) ELECTRODE WITH RELATIVELY LOW RADIUS OF CURVATURE

[0060] Another aspect, which is provided, is associated with the manner by which the reactor 10 is configured for generating a plasma. The reactor 10 includes an electrode surface portion with a relatively low radius of curvature for, amongst other things, facilitating an electrical discharges at a relatively lower applied electrical potential difference.

[0061] Referring to Figure 2, the reactor 10 includes an internal space 26 including a reaction zone 32. The reactor 10 also includes a plasma generator 34. The plasma generator 34 includes a first electrode 36 and a second electrode. The first electrode 36 is configured for electrical coupling to a current and voltage source 44. The second electrode 52 is spaced apart from and disposed in electrical discharge communication with the first electrode 36 through the internal space 26, and includes an operative second electrode surface portion 54. For example, the second electrode 52 is a ground electrode. Referring specifically to Figure 5, the operative second electrode surface portion 54 is defined by a radius of curvature of less than 0.002 inches. In some embodiments, for example, the radius of curative is between 0.002 inches and 0.0055 inches. In some embodiments, for example, the radius of curvature is as small as permitted by existing manufacturing techniques so as to facilitate generation of a larger electric field, which eases the ignition process of the plasma. The reaction zone 32 is disposed between the first and second electrodes 36, 52.

[0062] Referring to Figures 5, 10, and 12, when a plasma forming gaseous fluid is disposed within the reaction zone 32 and a sufficient electrical potential difference is applied between the first electrode 36 and the operative second electrode surface portion 54, an electrical discharge is effected between the first electrode 36 and the operative second electrode surface portion 54 and through the reaction zone 32, and at least a fraction of the plasma forming gaseous fluid is converted into a plasma 102.

[0063] In some embodiments, the operative second electrode surface portion 54 is defined by an edge 58. For example, the reactor 10 includes an internal surface 28 defining the internal space 26, and the operative second electrode surface portion 54 is the conductive surface portion of the internal surface 28 which is closest to the first electrode 36.

[0064] In some embodiments, the reactor 10 includes a fluid passage which includes the reaction zone 32. Referring to Figure 5, for example, the fluid passage includes upstream and downstream fluid passage portions 66, 74, and the operative second electrode surface portion 54 defines an orifice 92 which effects fluid communication between the upstream fluid passage portion 66 and the downstream fluid passage portion 74.

[0065] In a related aspect, a method of operating any of the above-described embodiments of the reactor 10 in (B) is provided. The method includes contacting reactant matter with a plasma in a reaction zone 32, wherein the pressure in the reaction zone 32 is at least 75 psig.

[0066] In some embodiments, the plasma is plasma generated by providing a plasma forming fluid in the reaction zone 32, and applying a sufficient electrical potential difference between the first electrode 36 and the operative second electrode surface portion 54, so as to effect an electrical discharge between the first electrode 36 and the operative second electrode surface portion 54 and through the reaction zone 32. As a result, at least a fraction of the plasma forming gaseous fluid is converted into a plasma 102.

[0067] In some embodiments, the plasma forming fluid includes reactant matter. In some embodiments, the reactant matter includes natural gas. For example, the reactant matter includes methane.

(C) MITIGATING DEPOSITION OF PRODUCED SOLID PARTICULATE ON ELECTRODE MOUNTING STRUCTURE

[0068] A further aspect includes providing a reactor 10 configured for generating a plasma by virtue of an electrical discharge between first and second electrodes 36, 52, and providing a minimum distance between an operative second electrode surface portion 54 of the second electrode 52 and a mounting structure 46 for mounting the first electrode 36. Amongst other things, by providing this minimum distance, deposition of solid particulate, such as particulate carbon, generated by a reactive process effected by the generated plasma, upon the mounting structure 46 is mitigated. Such deposition could otherwise facilitate undesirable arcing between the mounting structure 46 and the first electrode 46.

[0069] Referring to Figure 2 the mounting structure 46 includes an internal mounting structure surface 48 defining a portion of the internal surface 28. The internal mounting structure surface 48 is defined by an electrically non-conductive material 49 of the mounting structure 46. With respect to the electrically non-conductive material 49, in some embodiments, for example, the electrically non-conductive material 49 defining the internal mounting structure surface 48 is disposed between the first electrode 36 and electrically conductive material, wherein such electrically conductive material is disposed within the reaction vessel 12 and in closer proximity to the first electrode 36 relative to the second electrode 52. For example, the electrically non-conductive material 49 includes a polymeric material, such as TEFLON™.

[0070] In some embodiments, for example, the reaction vessel 12 includes an internal reaction vessel wall 14, and the electrically non-conductive material 49 extends to the internal reaction vessel wall 14 such that a reaction zone remote electrically non- conductive material surface 481 is provided in abutting relationship with the internal reaction vessel wall 14. For example, the internal reaction vessel wall 14 includes an electrically conductive internal reaction vessel wall portion 16 and, in some embodiments, the electrically conductive internal reaction vessel wall portion 16 is disposed in closer proximity to the first electrode 36 relative to the second electrode 52. The electrically non-conductive material 49, in such cases, insulates the electrically conductive internal reaction vessel wall portion 16 from the first electrode 36.

[0071] In some embodiments, for example, the mounting structure 46 is the high voltage feedthrough assembly 300.

[0072] The reactor 10 includes an internal surface 28 defining an internal space 26 including a reaction zone 32. The reactor 10 also includes a plasma generator 34. The plasma generator 34 includes a first electrode 36 and a second electrode 52. The first electrode 36 is configured for electrical coupling to a current and voltage source 44. The second electrode 52 is spaced apart from and disposed in electrical discharge communication with the first electrode 36 through the internal space 26. The second electrode 52 further includes an operative second electrode surface portion 54. For example, the second electrode 52 is a ground electrode. The reaction zone 32 is disposed between the first electrode 36 and the operative second electrode surface portion 54.

[0073] The first electrode 36 is mounted within a reaction vessel 12 with a mounting structure 46. The internal mounting structure surface 48 includes an internal mounting structure surface portion 482 defining a portion of the internal surface 28. The internal mounting structure surface portion 482 is disposed in fluid communication with the reaction zone 32. Referring specifically to Figure 8, the minimum distance Dl between the operative second electrode surface portion 54 and the internal mounting structure surface portion 48 is at least two (2) inches. The minimum distance Dl varies depending on the fluid flow characteristics in the reaction zone 32.

[0074] Referring to Figures 5, 10, and 12, when a plasma forming gaseous fluid is disposed within the reaction zone 32 and a sufficient electrical potential difference is applied between the first electrode 36 and the operative second electrode surface portion 54, an electrical discharge is effected between the first electrode 36 and the operative second electrode surface portion 54 and through the reaction zone 32. At least a fraction of the plasma forming gaseous fluid disposed in the reaction zone 32 is converted into a plasma 102.

[0075] In some embodiments, for example, the operative second electrode surface portion 54 is the electrically conductive surface portion of the internal surface 28 which is closest to the first electrode 36.

[0076] In some embodiments, the internal mounting structure surface portion 48 is electrically non-conductive. For example, the mounting structure surface portion 48 includes a solid particulate deposition susceptible mounting surface portion 50 configured for becoming coupled to a solid particulate upon approach of the solid particulate to the solid particulate deposition susceptible mounting surface portion 50. For example, the solid particulate includes carbon-comprising particulate, such as particulate carbon.

[0077] For example, with respect to the upstream fluid passage portion 66, in some embodiments, the upstream fluid passage portion 66 is defined by an upstream conduit wall 68 disposed upstream of the reaction zone 32, wherein the upstream conduit wall 68 includes at least one electrically conductive upstream conduit wall surface portion 70. Further, any electrically conductive upstream conduit wall surface portion 70, which is disposed in electrical discharge communication with the first electrode 36, is disposed further from the first electrode 36 than the operative second electrode surface portion 54. Referring to Figure 4, in some embodiments, for example, any electrically conductive upstream conduit wall surface portion 70 of the upstream conduit wall 68 that is spaced apart from the mounting structure by a minimum distance of D6 of at least 1.118 inches is also spaced apart from the first electrode 36 by a minimum distance D7 that is greater than 0.5 inches . In some embodiments, for example, any electrically conductive upstream conduit wall surface portion 70 of the upstream conduit wall 68 that is spaced apart from the mounting structure by a minimum distance of D6 of 1.39 inches is also spaced apart from the first electrode 36 by a minimum distance D7 of 0.845 inches.

[0078] For example, with further respect to the upstream fluid passage portion 66, in some embodiments, the upstream conduit wall 68 includes an upstream solid particulate deposition susceptible conduit wall surface portion 72 configured for becoming coupled to a solid particulate upon approach of the solid particulate to the upstream solid particulate deposition susceptible conduit wall surface portion 72. For example, the solid particulate includes carbon-comprising particulate, such as particulate carbon.

[0079] For example, with further respect to the upstream fluid passage portion 66, in some embodiments, the upstream fluid passage portion 66 extends between the reaction zone 32 and the mounting structure 46.

[0080] In some embodiments, and with reference to Figure 2, the internal space 26 includes a fluid passage portion 64 for flowing a plasma forming gaseous fluid through the reaction zone 32. The fluid passage portion 64 includes an upstream fluid passage portion 66 disposed upstream of the reaction zone 32 and between the mounting structure 46 and the reaction zone 32. The fluid passage portion 64 also includes a downstream fluid passage portion 74 extending downstream from within the reaction zone 32. In some embodiments, for example, the downstream fluid passage portion 74 is defined by a downstream internal conduit surface 76 including a downstream solid particulate deposition susceptible conduit surface portion 78. The downstream solid particulate deposition susceptible conduit surface portion 78 is configured for becoming coupled to a solid particulate upon approach of the solid particulate to the downstream solid particulate deposition susceptible conduit surface portion 78.

[0081] In a related aspect, there is provided a method of operating any of the above- described embodiments of the reactor 10 in (C). The method includes contacting reactant matter with a plasma in a reaction zone 32 to effect production of product matter including solid particulate, such as carbon-comprising particulate. For example, the solid particulate is carbon particulate.

[0082] In some embodiments, the plasma is plasma generated by providing a plasma forming fluid in the reaction zone 32, and applying a sufficient electrical potential difference between the first electrode 36 and the operative second electrode surface portion 54, so as to effect an electrical discharge between the first electrode 36 and the operative second electrode surface portion 54 and through the reaction zone 32. As a result, at least a fraction of the plasma forming gaseous fluid is converted into a plasma 102.

[0083] With respect to the plasma forming fluid, in some embodiments, for example, the plasma forming fluid includes a plasma forming fluid flow.

[0084] With further respect to the plasma forming fluid, in some embodiments, for example, the plasma forming fluid includes reactant matter. In some embodiments, the reactant matter includes natural gas. For example, the reactant matter includes methane.

[0085] In some embodiments, there is provided a carrier fluid flow for sweeping produced solid particulate from the reaction zone 32. The downstream fluid passage portion 74 is defined by a downstream internal conduit surface 76 including a downstream solid particulate deposition susceptible conduit surface portion 78, wherein the downstream solid particulate deposition susceptible conduit surface portion 78 is configured for becoming coupled to the produced solid particulate upon approach of the produced solid particulate to the downstream solid particulate deposition susceptible conduit surface portion 78.

[0086] With respect to the carrier fluid flow, in some embodiments, for example, the minimum velocity of carrier fluid flow is 0.4 metres per second to 0.5 metres per second for flow through a circular fluid passage of a diameter of 0.4 inches. Further, in some embodiments, for example, the minimum velocity of carrier fluid flow is 0.5 metres per second to 0.6 metres per second for flow through a circular fluid passage of a diameter of 0.3 inches.

[0087] With further respect to the carrier fluid flow, in some embodiments, for example, at least a fraction of the carrier fluid flow is derived from the plasma forming fluid flow. In some embodiments, for example, the carrier fluid flow is entirely derived from the plasma forming fluid flow.

(D) DEFINING MAXIMUM DISTANCE BETWEEN ELECTRODES TO MITIGATE ELECTRICAL DISCHARGES AT NON-PREFERRED SURFACES

[0088] Another aspect, which is provided, is associated with a reactor 10 configured for generating a plasma. A maximum distance between electrodes is provided for, amongst other things, mitigating against the formation of a higher temperature environment at the electrodes during electrical discharge between the electrodes. Such higher temperatures would then effect formation of higher temperatures at non-preferred surfaces through heat transfer, and increase the likelihood of electrical discharge at these non-preferred surfaces.

[0089] Referring to Figure 2, the reactor 10 includes a fluid passage portion 64 for flowing a plasma forming gaseous fluid. The fluid passage portion 64 includes a reaction zone 32. The fluid passage portion 64 includes an upstream fluid passage portion 66 and a downstream fluid passage portion 74. The upstream fluid passage portion 66 is defined by an upstream conduit wall 68 disposed upstream of the reaction zone 32, wherein the upstream conduit wall 68 includes at least one electrically conductive upstream conduit wall 68 portion. The downstream fluid passage portion 74 extends downstream from within the reaction vessel 32.

[0090] The reactor 10 also includes a plasma generator 34. The plasma generator 34 includes a first electrode 36 and a second electrode 52. The first electrode 36 is configured for electrical coupling to a current and voltage source 44. The second electrode 52 is spaced apart from and disposed in electrical discharge communication with the first electrode 36 through the internal space 26. For example, the second electrode 52 is a ground electrode. The second electrode 52 includes an operative second electrode surface portion 54. The reaction zone 32 is defined between the first electrode 36 and the operative second electrode surface portion 54. Referring to Figure 9, the operative second electrode surface portion 54 is spaced apart from the first electrode 36 by a minimum distance D2 of less than 0.15 inches. For example, in some embodiments, the minimum distance D2 is greater than 0.075 inches. In this respect, in some embodiments, for example, if D2 is too small, power transfer in the plasma may be undesirably limiting. For example, in some embodiments, the minimum distance D2 is between 0.075 inches and 0.15 inches.

[0091] Referring to Figures 5, 10, and 12, when the plasma forming gaseous fluid is disposed in the reaction zone 32 and a sufficient electrical potential difference is applied between the first electrode 36 and the operative second electrode surface portion 54, an electrical discharge is effected between the first electrode 36 and the operative second electrode surface portion 54 and through the reaction zone 32, and at least a fraction of the plasma forming gaseous fluid is converted into a plasma 102.

[0092] The operative second electrode surface portion 54 is disposed in thermal communication with at least one electrically conductive upstream conduit wall portion 70. Any of the at least one electrically conductive upstream conduit wall portion 70, that is disposed in electrical discharge communication with the first electrode 36, is disposed further from the first electrode 36 than the operative second electrode surface portion 54. Amongst other things, disposition of the operative second electrode surface portion 54 from the first electrode 36 beyond the above-described maximum distance increases the likelihood that heat is generated during the electrical discharge at the operative second electrode surface portion 54 and effects heating of an electrically conductive upstream conduit wall portion 70 to a temperature which is effective to facilitate an electrical discharge between the first electrode 36 and the electrically conductive upstream conduit wall portion 70. It is preferred to effect electrical discharge further downstream, rather than upstream, so as to effect reduced residence time of any produced solid particulate in the reactor 10 and thereby mitigate against deposition, within the reactor 10, of the produced solid particulate.

[0093] With respect to the upstream conduit wall 68, in some embodiments, for example, the upstream conduit wall 68 includes an upstream solid particulate deposition susceptible conduit wall portion 72 configured for becoming coupled to the solid particulate upon approach of solid particulate to the upstream solid particulate deposition susceptible conduit wall portion 72.

[0094] With respect to the downstream fluid passage portion 74, in some embodiments, for example, the downstream fluid passage portion 74 is defined by a downstream internal conduit surface 76 including a downstream solid particulate deposition susceptible conduit surface portion 78. The downstream solid particulate deposition susceptible conduit surface portion 78 is configured for becoming coupled to solid particulate upon approach of the solid particulate to the downstream solid particulate deposition susceptible conduit surface portion 78.

[0095] In some embodiments, for example, the reaction zone 32 is provided in an internal space 26 defined by an internal surface 28 of the reactor 10, and the operative second electrode surface portion 54 is the electrically conductive surface portion of the internal surface 28 which is closest to the first electrode 36.

[0096] In some embodiments, for example, the upstream conduit wall 68 merges with the operative second electrode surface portion 54. [0097] In a related aspect, there is provided a method of operating any of the above- described embodiments of the reactor 10 in (D). The method includes contacting reactant matter with a plasma in a reaction zone 32 to effect production of product matter including solid particulate such as carbon-comprising particulate. For example, the solid particulate is carbon particulate.

[0098] In some embodiments, the plasma is plasma generated by providing a plasma forming fluid in the reaction zone 32, and applying a sufficient electrical potential difference between the first electrode 36 and the operative second electrode surface portion 54, so as to effect an electrical discharge between the first electrode 36 and the operative second electrode surface portion 54 and through the reaction zone 32. As a result, at least a fraction of the plasma forming gaseous fluid is converted into a plasma 102.

[0099] With respect to the plasma forming fluid, in some embodiments, for example, the plasma forming fluid includes a plasma forming fluid flow.

[00100] With further respect to the plasma forming fluid, in some embodiments, for example, the plasma forming fluid includes reactant matter. In some embodiments, the reactant matter includes natural gas. For example, the reactant matter includes methane.

[00101] In some embodiments, for example, there is further provided a carrier fluid flow for sweeping carbon from the reaction zone 32. In this respect, for example, the downstream fluid passage portion 74 is defined by a downstream internal conduit surface 76 including a downstream solid particulate deposition susceptible conduit surface portion 78. The downstream solid particulate deposition susceptible conduit surface portion 78 is configured for becoming coupled to the produced solid particulate upon approach of the produced solid particulate to the downstream solid particulate deposition susceptible conduit surface portion 78 Amongst other things, the carrier fluid flow mitigates against such deposition. In some embodiments, for example, the minimum velocity of carrier fluid flow is 0.5 metres per second to 0.6 metres per second for flow through the downstream fluid passage portion 74 having an internal diameter of 0.3 inches. In some embodiments, for example, at least a fraction of the carrier fluid flow is derived from the plasma forming fluid flow.

(E) PROVIDING SUFFICIENT ELECTRODE SURFACE AREA TO EFFECT COOLING OF THE ELECTRODE WHILE PROVIDING SUFFICIENT SPACE TO EFFECT DESIRED CONVERSION OF REACTANTS WHILE MITIGATING SOLID PARTICULATE DEPOSITION

[00102] Another aspect, which is provided, is associated with a reactor 10 configured for generating a plasma. This aspect provides, within a fluid passage within the reactor 10, an electrode with a defined electrode surface area which, amongst other things, effects cooling of the electrode while allowing sufficient space to effect desired conversion of reactants while mitigating against solid particulate deposition.

[00103] Referring to Figure 2, the reactor 10 includes a fluid passage portion 64 for flowing a plasma forming gaseous fluid. The fluid passage portion 64 includes an upstream fluid passage portion 66 and a downstream fluid passage portion 74. The reactor 10 also includes a plasma generator 34. The plasma generator 34 includes a first electrode 36 and a second electrode 52. The first electrode 36 is configured for electrical coupling to a current and voltage source 44. The second electrode 52 is spaced apart from and disposed in electrical discharge communication with the first electrode 36 through the internal space 26. For example, the second electrode 52 is a ground electrode.

[00104] A reaction zone 32 is defined within the fluid passage portion 64 between the first electrode 36 and the second electrode 52. The downstream fluid passage portion 74 extends downstream from within the reaction zone 32. The upstream fluid passage portion 66 is disposed upstream of the reaction zone 32.

[00105] Referring to Figures 5, 10, and 12, when the plasma forming gaseous fluid is disposed within the reaction zone 32 and a sufficient electrical potential difference is applied between the first electrode 36 and the second electrode 52, an electrical discharge is effected between the first electrode 36 and the second electrode 52 and through the reaction zone 32, and at least a fraction of the plasma forming gaseous fluid is converted into a plasma 102.

[00106] Referring to Figures 10 and 1 1 , the first electrode 36 is at least partially disposed in the downstream fluid passage portion 74 and is spaced apart from an internal conduit wall 76, which defines the downstream fluid passage portion 74 to define a fluid flow space 741 in the downstream fluid passage portion 74 between the first electrode 36 and the internal conduit wall 76. In any plane 200 which intersects that portion of the first electrode 36 disposed in the downstream fluid passage portion 74, and which is disposed in a normal orientation relative to an axis 741 1 of the downstream fluid passage portion 74 being intersected, the ratio of the diameter D3 of the first electrode 36 to the diameter D4 of the downstream fluid passage portion 74 is between two (2) and five (5). For example, in some embodiments, this ratio is three (3).

[00107] With respect to the second electrode 52, in some embodiments, for example, the second electrode 52 includes an operative second electrode surface portion 54. When the plasma forming gaseous fluid is disposed within the reaction zone 32 and a sufficient electrical potential difference is applied between the first electrode 36 and the operative second electrode surface portion 54, the effected electrical discharge is between the first electrode 36 and the operative second electrode surface portion 54 and at least a fraction of the plasma forming gaseous fluid is converted into a plasma 102.

[00108] In some embodiments, for example, the reaction zone 32 is provided in an internal space 26 defined by an internal surface 28 of the reactor 10, and the operative second electrode surface portion 54 is the electrically conductive surface portion of the internal surface 28 which is closest to the first electrode 36.

[00109] With respect to the upstream fluid passage portion 66, in some embodiments, for example, the upstream fluid passage portion 66 is defined by an upstream conduit wall 68 disposed upstream of the reaction zone 32. The upstream conduit wall 68 includes at least one electrically conductive upstream conduit wall portion 70. Any electrically conductive upstream conduit wall portion 70, which is disposed in electrical discharge communication with the first electrode 36, is disposed further from the first electrode 36 than the operative second electrode surface portion 54.

[00110] With further respect to the upstream fluid passage portion 66, in some embodiments, for example, the upstream conduit wall 68 includes an upstream solid particulate deposition susceptible conduit wall portion 72 configured for becoming coupled to solid particulate upon approach of the solid particulate to the upstream solid particulate deposition susceptible conduit wall portion 72.

[00111] With respect to the downstream fluid passage portion 74, in some embodiments, for example, the downstream fluid passage portion 74 is defined by a downstream internal conduit surface 76 including a downstream solid particulate deposition susceptible conduit surface portion 78. The downstream solid particulate deposition susceptible conduit surface portion 78 is configured for becoming coupled to solid particulate upon approach of the solid particulate to the downstream solid particulate deposition susceptible conduit surface portion 78.

[00112] In a related aspect, there is provided a method of operating any of the above- described embodiments of the reactor 10 in (E). The method includes contacting reactant matter with a plasma in a reaction zone 32 to effect production of product matter including solid particulate such as carbon-comprising particulate. For example, the solid particulate is carbon particulate.

[00113] In some embodiments, the plasma is plasma generated by providing a plasma forming fluid in the reaction zone 32, and applying a sufficient electrical potential difference between the first electrode 36 and the operative second electrode surface portion 54, so as to effect an electrical discharge between the first electrode 36 and the second electrode 52 (and, in some embodiments, the operative second electrode surface portion 54) and through the reaction zone 32. As a result, at least a fraction of the plasma forming gaseous fluid is converted into a plasma 102.

[00114] With respect to the plasma forming fluid, in some embodiments, for example, the plasma forming fluid includes a plasma forming fluid flow. [00115] With further respect to the plasma forming fluid, in some embodiments, for example, the plasma forming fluid includes reactant matter. In some embodiments, the reactant matter includes natural gas. For example, the reactant matter includes methane.

[00116] In some embodiments, for example, there is further provided a carrier fluid flow for sweeping carbon from the reaction zone 32. In this respect, for example, the downstream fluid passage portion 74 is defined by a downstream internal conduit surface 76 including a downstream solid particulate deposition susceptible conduit surface portion 78. The downstream solid particulate deposition susceptible conduit surface portion 78 is configured for becoming coupled to the produced solid particulate upon approach of the produced solid particulate to the downstream solid particulate deposition susceptible conduit surface portion 78 Amongst other things, the carrier fluid flow mitigates against such deposition. In some embodiments, for example, the minimum velocity of carrier fluid flow is 0.5 metres per second to 0.6 metres per second for flow through the downstream fluid passage portion 74 having an internal diameter of 0.3 inches. In some embodiments, for example, at least a fraction of the carrier fluid flow is derived from the plasma forming fluid flow.

(F) INCREASING SERVICE LIFE OF ELECTRODE

[00117] Another aspect is provided associated with a reactor 10 configured for generating a plasma, which, amongst other things, effects increased service life of the electrode.

[00118] Referring to Figure 2, the reactor 10 includes an internal space 26 defining a fluid passage portion 64 for flowing a plasma forming gaseous fluid. The fluid passage portion 64 includes a reaction zone 32. The reactor 10 also includes a plasma generator 34. The plasma generator 34 includes a first electrode 36 and a second electrode 52. The first electrode 36 is configured for electrical coupling to a current and voltage source 44, and includes an operative first electrode surface portion 38. The second electrode 52 is spaced apart from and disposed in electrical discharge communication with the first electrode 36 through the internal space 26, and includes an operative second electrode surface portion 54. For example, the second electrode 52 is a ground electrode. The reaction zone 32 is disposed between the first and second electrodes 36, 52.

[00119] When a plasma forming gaseous fluid is disposed within the reaction zone 32 and a sufficient electrical potential difference is applied between the operative first electrode surface portion 38 and the operative second electrode surface portion 54, an electrical discharge is effected between the operative first electrode surface portion 38 and the operative second electrode surface portion 54 and through the reaction zone 32, and at least a fraction of the plasma forming gaseous fluid is converted into a plasma 102.

[00120] Referring to Figure 12, an operative distance D5 is defined along the longitudinal axis 36 of the first electrode 36 between: (i) a plane in which is disposed an axis normal to the operative first electrode surface portion 38, and (ii) a tip 100 of the first electrode 36, disposed downstream of the operative first electrode surface portion 38, wherein the operative distance D5 is at least 0.25 inches. For example, in some embodiments, the operative distance D5 is less than 1.25 inches. For example, in some embodiments, the operative distance D5 is one inch. By providing this minimum operative distance, amongst other things, the reactor 10 is able to operate for longer durations before requiring replacement of the first electrode 36.

[00121] In some embodiments, for example, the reaction zone 32 is provided in an internal space 26 defined by an internal surface 28 of the reactor 10, and the operative second electrode surface portion 54 is the electrically conductive surface portion of the internal surface 28 which is closest to the first electrode 36.

[00122] In a related aspect, there is provided a method of operating any of the above- described embodiments of the reactor 10 in (F). The method includes contacting reactant matter with a plasma in a reaction zone 32 to effect production of product matter including solid particulate.

[00123] Referring to Figures 5, 10, and 12, in some embodiments, the plasma is plasma generated by providing a plasma forming fluid in the reaction zone 32, and applying a sufficient electrical potential difference between the first electrode 36 and the operative second electrode surface portion 54, so as to effect an electrical discharge between the first electrode 36 and the operative second electrode surface portion 54 and through the reaction zone 32. As a result, at least a fraction of the plasma forming gaseous fluid is converted into a plasma 102.

[00124] With respect to the plasma forming fluid, in some embodiments, for example, the plasma forming fluid includes a plasma forming fluid flow.

[00125] With further respect to the plasma forming fluid, in some embodiments, for example, the plasma forming fluid includes reactant matter. In some embodiments, the reactant matter includes natural gas. For example, the reactant matter includes methane.

[00126] In some embodiments, for example, the plasma 102 is generated in the reaction zone 32, and the pressure in the reaction zone 32 is at least 75 psig. By providing this pressure in the reaction zone 32, and amongst other things, there is effected a greater residence time for the reactant matter in the reaction zone, which effects a greater reaction conversion of reactant matter, and which, as a corollary, effects greater generation of heat, and thereby effects creation of conditions which could, amongst other things, acceleration electrode erosion. In this respect, and amongst other things, the operative distance D5 is provided to mitigate against these consequences.

(G) HEAT EXCHANGER FOR EFFECTING HEATING OF PLASMA FORMING FLUID BEING INTRODUCED INTO REACTION ZONE

[00127] Another aspect, which is provided, is associated with a reactor 10 configured for generating a plasma, which, amongst other things, includes a heat exchanger 18 for effecting heating of plasma forming fluid being introduced into the reactor 10.

[00128] Referring to Figure 7, there is provided a reactor 10 including an internal space 26 including a reaction zone 32. The reactor includes an inlet 20 fluidly coupled to the reaction zone 32 with a fluid introduction passage 24 for introducing a plasma forming gaseous fluid into the reaction zone 32. The reactor 10 also includes a plasma generator 34. The plasma generator 34 includes a first electrode 36 and a second electrode 52. The first electrode 36 is configured for electrical coupling to a current and voltage source 44. The second electrode 52 is spaced apart from and disposed in electrical discharge communication with the first electrode 36 through the internal space 26. The reaction zone 32 is disposed between the first and second electrodes 36, 52.

[00129] When a plasma forming gaseous fluid is disposed within the reaction zone 32 and a sufficient electrical potential difference is applied between the first electrode 36 and the second electrode 52, an electrical discharge is effected between the first electrode 36 and the second electrode 52 and through the reaction zone 32, and at least a fraction of the plasma forming gaseous fluid is converted into a plasma.

[00130] The reaction vessel 12 includes a heat exchanger 18 disposed in heat transfer communication with the fluid introduction passage 24 for effecting heat transfer to plasma forming gaseous fluid being introduced to the reaction zone 32.

[00131] In some embodiments, for example, the heat exchanger 18 includes an induction heater.

[00132] In a related aspect, there is provided a method of operating any of the above- described embodiments of the reactor 10 in (G). The method includes contacting reactant matter with a plasma in a reaction zone 32 to effect production of product matter.

[00133] In some embodiments, the plasma is plasma generated by providing a plasma forming fluid in the reaction zone 32, and applying a sufficient electrical potential difference between the first electrode 36 and the second electrode 52, so as to effect an electrical discharge between the first electrode 36 and the second electrode 52 and through the reaction zone 32. As a result, at least a fraction of the plasma forming gaseous fluid is converted into a plasma. The plasma forming fluid is heated by the heat exchanger 18. In some embodiments, the plasma forming fluid is heated by the heat exchanger 18 to a temperature of between 400°C and 700°C from any defined temperature.

[00134] With respect to the plasma forming fluid, in some embodiments, for example, the plasma forming fluid includes a plasma forming fluid flow. [00135] With further respect to the plasma forming fluid, in some embodiments, for example, the plasma forming fluid includes reactant matter. In some embodiments, the reactant matter includes natural gas. For example, the reactant matter includes methane.

(H) OPERATING A REACTOR AT ELEVATED TEMPERATURES

[00136] Another aspect is provided relating to the method of operating a plasma reactor 10. Amongst other things, this aspect effects heat transfer from an electrode at a sufficiently desirable rate so as to mitigate against providing high temperatures at the electrode which would facilitate deposition of solid particulate at the electrode.

[00137] Referring to Figure 2, a plasma reactor 10 is provided including an internal surface 28 defining an internal space 26 including a reaction zone 32. The plasma reactor also includes a plasma generator 34. The plasma generator 34 includes a first electrode 36 and a second electrode 52. The first electrode 36 is configured for electrical coupling to a current and voltage source 44. The second electrode 52 is spaced apart from and disposed in electrical discharge communication with the first electrode 36 through the internal space 26. For example, the second electrode 52 is a ground electrode. The reaction zone 32 is disposed between the first and second electrode 36, 52.

[00138] A plasma forming gaseous fluid is provided within the reaction zone 32.

[00139] Referring to Figure 10, when an electrical potential difference is applied between the first electrode 36 and the second electrode 52 sufficient to effect an electrical discharge between the first electrode 36 and the second electrode 52 and through the reaction zone 32, at least a fraction of the provided plasma forming gaseous fluid is converted into plasma 102.

[00140] Referring to Figure 10, the plasma reactor 10 includes a pressure boundary 960, which includes an internal surface portion 96 adjacent to and in thermal communication with the reaction zone 32, and which also defines an extemalmost surface 962 which is disposed in heat transfer relationship with the outside environment 1000 (ie. the atmosphere). In some embodiments, for example, the internal surface portion 96 is defined by the second electrode 52. The material of the pressure boundary 960 is characterized by an average heat transfer coefficient of at least 100 W / (meter-Kelvin). In some embodiments, for example, this average heat transfer coefficient is between 100 W / (meter-Kelvin) and 200 W / (meter-Kelvin). In some embodiments, for example, this average heat transfer coefficient is 173 W / (meter-Kelvin).

[00141] In some embodiments, for example, the pressure boundary 960 includes a heat transfer medium 94. In some embodiments, for example, the heat transfer medium 94 includes steel wool. In other embodiments, for example, the heat transfer medium includes copper.

[00142] With respect to the plasma forming fluid, in some embodiments, for example, the plasma forming fluid includes a plasma forming fluid flow.

[00143] With further respect to the plasma forming fluid, in some embodiments, for example, the plasma forming fluid includes reactant matter. In some embodiments, the reactant matter includes natural gas. For example, the reactant matter includes methane.

[00144] In the above description, for purposes of explanation, numerous details are set forth in order to provide a thorough understanding of the present disclosure. However, it will be apparent to one skilled in the art that these specific details are not required in order to practice the present disclosure. In other instances, well-known electrical structures and circuits are shown in block diagram form in order not to obscure the present disclosure. Although certain dimensions and materials are described for implementing the disclosed example embodiments, other suitable dimensions and/or materials may be used within the scope of this disclosure. All such modifications and variations, including all suitable current and future changes in technology, are believed to be within the sphere and scope of the present disclosure. All references mentioned are hereby incorporated by reference in their entirety. APPENDIX "A" - REACTIONS

The dominant reactions that initiate the process

e + CH => CH ₃ + H + e

e + CH ₄ => CH ₂ + H ₂ + e

e + CH ₄ => CH + H ₂ + H + e

e + CH4 => CH3 + H* + e

Other reactions include:

Reaction

e + CH ₄ => CH ₃ + H* + e

e + CH ₄ => CH* + H ₂ + H + e

e + CH ₄ =>CH ₃ ⁺ + H + 2e

e + CH ₄ =>CH ₂ ⁺ + H ₂ + 2e

e + CH ₄ =>C ⁺ + 4H* + 2e

e + C ₂ H ₄ =>C ₂ H ₄ ⁺ + 2e

e + C ₂ H ₆ => C ₂ H ₄ ⁺ + H ₂ + 2e e + C ₂ H ₂ =>C ₂ H ₂ ⁺ + 2e

e + C ₃ H ₈ => C ₂ H ₅ ⁺ + CH ₃ + 2e

Electron-impact reactions of Hydrogen e + H ₂ => H ₂ + e

e + H ₂ => H ₂ + e

e + H ₂ => H ₂ + e

e + H ₂ => H + H + e

e + H ₂ => H ₂ ⁺ + 2e

e + H => H + e

e + H => H ⁺ + 2e

II. Ion-Molecule Reaction

C ⁺ + CH ₄ => C ₂ H ₂ ⁺ +H ₂

C ⁺ + CH ₄ => C ₂ H ₃ ⁺ +H

CH ⁺ + CH ₄ =>C ₂ H ₂ ⁺ +H ₂ + H

CH ⁺ + CH ₄ => C ₂ H ₃ ⁺ +H ₂

CH ⁺ + CH ₄ => C ₂ H ₄ ⁺ + H

CH ⁺ + H ₂ => CH ₂ ⁺ + H

CH ₂ ⁺ + CH ₄ => C ₂ H ₄ ⁺ + H ₂

CH ₂ ⁺ + CH ₄ => C ₂ H ₅ ⁺ + H

CH ₂ ⁺ + H ₂ => CH ₃ ⁺ + H

CH ₂ ⁺ + CH ₄ => CH ₃ ⁺ +CH ₃ Reaction

CH ₂ ⁺ + CH ₄ =>C ₂ H ₃ ⁺ + H + H ₂

CH ₃ ⁺ + CH ₄ => CH ₄ ⁺ + CH ₃

CH ₄ ⁺ + CH ₄ => CH ₅ ⁺ + CH ₃

CH ₄ ⁺ + H ₂ => CH ₅ ⁺ + H

CH ₅ ⁺ +C ₂ H ₆ =>C ₂ H ₅ ⁺ +H ₂ +CH ₄

C ₂ H ₂ ⁺ + CH ₄ => C ₂ H ₃ ⁺ + CH ₃

C ₂ H ₂ ⁺ + CH ₄ => C ₃ H ₅ ⁺ + H

C ₂ H ₃ ⁺ + CH ₄ => C ₃ H ₅ ⁺ + H ₂

C ₂ H ₃ ⁺ + C ₂ H ₄ =>C ₂ H ₅ ⁺ + C ₂ H ₂

C ₂ H ₃ ⁺ + C ₂ H ₂ => C ₄ H ₅ ⁺

C ₂ H ₄ ⁺ + C ₂ H ₄ =>C ₃ H ₅ ⁺ + CH ₃

C ₂ H ₄ ⁺ + C ₂ H ₄ => CH ₈ ⁺

C ₂ H ₄ ⁺ + C ₂ H ₆ =>C ₃ H ₆ ⁺ + CH ₄

C ₂ H ₄ ⁺ + C ₂ H ₆ =>C ₃ H ₇ ⁺ + CH ₃

C ₂ H ₅ ⁺ + C ₂ H ₄ =>C ₃ H ₅ ⁺ + CH ₄

C ₂ H ₅ ⁺ + C ₂ H ₃ => C ₄ H ₈ ⁺

H ₂ ⁺ +H ₂ =>H ₃ ⁺ + H

H ₃ ⁺ +CH ₄ =>CH ₅ ⁺ + H ₂

H ₃ ⁺ +C ₂ H ₂ =>C ₂ H ₃ ⁺ + H ₂

H ₃ ⁺ +C ₂ H ₄ =>C ₂ Hs ⁺ + H ₂

III. Neutral - Neutral Reactions

CH ₃ + CH ₃ = C ₂ H ₆

CH3 +CH3 = C ₂ H ₄ +H2

CH3 + H = CH4

CH3 + CH2 = C ₂ H ₄ + H

CH3 + H2 = CH4 + H

CH3 + CH3 = C ₂ H ₅ + H

CH3 + C2H6 = CH4 + C2H5

CH + C ₂ H ₄ = C ₃ H ₅