HYDRIDES ^'

PRIORITY DOCUMENT

[000.1 ] The present application claims priority from .Australian Provisional Patent Application No. 2015900389 tided "FULLERENE AND PERYLENE - A SOLID-STATE SYNTHESIS" and filed on 8 February 2015, the content of which is hereb incorporated b reference in its entirety.

INCORPORATION BY REFERENCE j 0002] The following publications are .referred to in the present application, and their contents are ^" hereb incorporated by reference in their entirety:

• Kharlamov A t al. Joint Synthesis of Small Carbon Molecules (Cj-Cn), Qua&i-Fulierenes (Cm, C*4s, C;5 ₂ ) a d dieir Hydrid.es, Chemical Engineering and Science, 2013, Vol. Ϊ, No. 3 , . ages 32- 40;

« Kharlamov, A et ah Mass Spectrometric Research of Hydrogenated Molecules of Carbon as Products of Pyrolysis ^" of Benzene and Pyridine Vapours, Chemical and Materials Engineering, 2013, Vol 1 , No. 4, Pages 122-131 ; and

• VehviMinen, T- X, etal Hydrogen interaction witli fiiflerenes:: From C ₃₀ to graphene, Pkvsic&l Review B 84, 085447 (201.1).

TECHNICAL FIELD

[0003 ] The present disclosure relates to processes for the production, of high molecul ar weight organi c molecu es by the dehydrogenatio of parent hy drocarbons, in a particular form the present discl sure relates to solid-state dehydrogenation processes that, can be used to synthesise high molecular weight products ox precursors which can be used in subsequent chemical processes.

BACKGROUND

[000 ] From die beginning of the science of chemistry, researchers- have been seeking ways to break up or build-up chemical confounds. All these endeavour are either in the pursuit of knowledge or commercial reward. Perhaps the best examples of systematic building up or breakin d w processes are carbo chemistry. [0005] One of the notable features evident in carbon chemistry is that carbon can bond with itself to form rings or chains and also it can combine with hydrogen in man ways. The addition of ^' hydrogen to a carbon system is called hydrogenation and the removal of hydrogen from a carbon system is called dehydrogenation. Generally, dehydrogenation promotes carbon atoms io bond with one other and the overall molecular weight of the products so formed increases when intermoleeular carbon-carbon bonds are formed during deh drogena tion.

{0006] In 1987, a new a!lotrope of carbon was discovered b Smalley, Heath, O'Brien and Kroto which was found to hold 60 carbon atoms bonded to each other in a form resemblin the appearance of a soccer ball. This allotrope is now well known, as or Mlerene. Almost immediately, researchers found that other carbon atoms could bond in specific numbers and the "higher fuHereoes" were isolated, among those being C ₇ «, C? _s , C ₇ §, and C _S4 . j 000? ] Earl methods for forming fulierenes involved carbon-arc soot, production followed by toluene extraction. Currently, fuMerenes are commonly produced by the controlled plasma decomposition of benzene, it has been known from the early stages of ftillereue research that "small fullerenes'' having a molecular weight of below€60 are possible in theory ^' but in. practice they arc more stable if they are attached to hydrogen atoms. The latter derivatives are referred to as fullerene hydrides.

[0008 ] Fuliercoe hydrides are now attracting attention for use in hydrogen fuel power because of their ability to be " ^■ accumulators' ^* or storage materials for hydrogen. Work so far indicates that fuUerene hydrides are able to adsorb hydrogen, on their surfaces and can be made to release it when required.

[0009 ] Current synthesis methods for iullerene hydrides involve variations on the- carbon-soot. rocess including pyrolysis of benzene/xylene at lower temperatures than used for C½, production:. The: equipment used resembles a combination of carbon-soot apparatus and a chemical vapour deposition method. .In practice it is difficult to control the process.

[001.0] There is thus a need to provide processes for the production of fulierenes and/or fullerene hydrides that overcome: one or more of the disadvan tages of known methods or provide a useful alternative method for producing fullerenes and/or fuUerene hydrides..

SUMMARY j 001 1 ] According to a first aspect of the present disclosure, there -is provided a solid-state- process for the d ehydrogena tion of hydrocarbons, wherein the process is carried out in a sealed reactor which ca be heated and pressurised. [0012 J in certain embodiments the process comprises: charging the pressure reactor with a precursor hydrocarbon material, an oxidising agent and an absorbent to adsorb or absorb one or more unwanted products of the dehydrogenarion; sealing the reactor and heating to a temperature and pressure for a time period; and after the time period .recovering dehydrogenated. hydrocarbon product from the reactor.

[0013] In certain embodiments the oxidising agent is selected from one or more of the group consisting of; copper oxide, manganese dioxide; lead oxides; sulphur; arid a combination of any two o more of the aforementioned oxidising agents.

[0014] In certain embodiments the absorbent is selected from one or more of the group consisting of: calcium oxide; zinc oxide; "Portland" cement; anhydrous calcium chloride; anhydrous, calcium sulfate; and a combination of any two or more of the aforementioned absorbents.

[00151 In certain embodiments the precursor hydrocarbon material is a poiyeyclic aromatic: hydrocarbon. In certain specific embodiments the poiyeyclic aromatic hydrocarbon is naphthalene.

[0016 j In certain embodiments the oxidi sing agent is copper oxide.

[0017] In certain embodiments the absorbent is calcium oxide.

[0018 ] in certain embodiments the pressure reactor is also charged with a catalyst. In certain specific embodiments the catalyst is nickel

[001 J In certain embodiments the dehydrogenated hydrocarbon products from the reactor are fullerenes or fullerene precursors or precursors for specialty organic chemicals.

[0020] In certain embodiments the dehydrogenated hydrocarbon products are recovered by a solvent extractio stage or stages.

1002.11 In certain embodiments the dehydrogenated hydrocarbon products are .further ^' subjected. to a treatme t with polymerisation agents or oxidisers or facilitators- and/or polymer modifiers.

[00221 In certain embodiments, the dehydrogenated hydrocarbon products are further treated with at least one dehydrogenation/polymerisation agent or facilitator. 10023 J in certain embodiments the dehydrogenation polymerisation agent or facilitator is selected from one or more of the group consistin of: ferric chloride; feme oxide; calcium chloride; calcium carbonate; lead dioxide; and photolysis.

}0024) According to a second aspect of the present disclosure, there is provided a dchykogenated hydrocarbon product formed by the process of the first aspect j 0025 ) According to a third aspect of the present disclosure, there is provided a reaction product, formed by th e proce ss of the first aspect.

BRIEF DESCRIPTION OF FIGURES

[0026] Embodiments of the present invention, will be discussed with reference to the accompanying figures wherein;

[0027] Figure 1 shows a mass spectrum (ESI_TOF) eonftnmrig the dehydrogciiation _: process;

[0028] Figure 2 shows a mass spectrum (MALDl) for a product application of the process;

[0029] Figure 3 shows a mass spectrum (MALDl) tor a product synthesised following an embodiment of the process; and

[00301 Figure 4 shows a mass spectrum (MALDl) for a product synthesised following another enihod irnent of the process .

DESCMPTIO OF EMBODIMENTS

[0031 ] Disclosed herein is a solid-state proeess for the dehydrogenation of hydrocarbons wherein the proeess is carried out in a sealed reactor which can be heated and pressurised. The process comprises: chargin the pressure reactor with a precursor hydrocarbon material, an oxidising agent and an absorbent to adsorb or absorb one or more unwanted products of the dehydrogenaiior« sealing the reactor and heating t a temperature and pressure fo a time period; and after the time period recoverin dertvdrogenated hydrocarbon product from the reactor. [0032 ] It should he noted that the process described herein is intended, for the dehydrogenation of

.hydrocarbons and these reactions are carried out in the solid-state at high temperatures and pressures,

[0033 ] To cany out the process, a robus elosable pressure reactor is required. The pressure reactor must be suitable for use in high pressure and high. temperature conditions without leakage. It roust also be constructed of metal or material which is chemically inert to the process or processes encountered. A suitable pressure reactor i n the form of a capsule can be prepared from a me di um carbon s teel suc h as type i 045 or an Austeoitk: stainless steel such as: type 316 and may comprise a capsule base and capsule lid -which- can be separated from one another so that the capsule can be charged with precursor materials and/or so that products can be remove from the capsule, and joined together in manner that allows the capsule to be safely used at the reaction temperatures- and pressures required. For example, the capsule base and lid may have a strong threaded connection. Other forms of connection known in the art can also be used, such a s clamps to hold the base and l i d together. The duty conditions of temperature , pressure, and chemical exposure arc well covered by existing engineering design standards and codes of practice for pressure vessels.

[0034] The capsule, hereafter referred to as the reactor, is charged with, a mixture of a hydrocarbon, and either an oxidising agent, a metallic oxide, a mixture of metallic oxides, or a combination of some or all of the abo ve mentioned.

[0035] The precursor hydrocarbon material may be a polycyctic aromatic hydrocarbon, such as naphthalene, anthracene, phenanthrene, etc or a mixture of po!ycyclic aromatic hydrocarbons.

[0036] A range of oxidising agents can be used. For example, the oxidising agent may be selected from one or more of the group consisting of: copper oxide, manganese dioxide; lead oxides, (i.e. lead (0.) oxide or lead (IV) oxide); sulphur; and a combination of any two o more of the aforementioned oxidising agents:.

[0037] The reactor is also charged with an ' ^' absorbent'* which is intimatel mixed with the oxidising agent(s). The role of the absorbent, is to act chemicall or physically to remo ve the water or other produc ts of dehydrogenation. as they are formed. As used herein, the terra "absorbent" should be understood to be used in a general sense to mean a. "sorbent" and include materials that absorb unwanted reaction products such as. water {i.e. an absorbent) and materials that adsorb unwanted reaction products such as water (i,c. an absorbent). As such., the absorbent can be any material that is able o adsorb or absorb water and retain the water under the reaction conditions used. The absorbent can. be a single chemical agent or a mixture of chemical compounds. Absorbents acting in this way allow the dehydrogenation process to proceed. When the role of the absorbent is to remove-water from the reaction, a suitable desieeant can be used. With this in mind, a range of materials known to the skilled person can be used. However, the absorbent needs to be chosen bearin in mind the temperature and pressure in the reactor so thai the temperature is not too high so as to eanse desorption. of the unwanted reaction products from the absorbent and the absorbent must not hinder the reaction between the oxidant and hydrocarbon. The absorbent may be selected from one or more of the group consisting of: calcium oxide; zinc oxide; "Portland" cement; anhydrous calcium chlori de; anhydrous e&lciuro sulfate; and a combination of any two or more of the afotcnientioned absorbents. Depending on tire reaction conditions, other desiceants such as silica, zeolites, activated charcoal etc. could also be used.

[0038] If required, a catalyst can be added to the reactor. The catalyst can be any ma erial that increases the rate of reaction. Nickel is suitable catalyst.

[0039] The reactor is heated to a desired temperature and a consequent internal pressure is

achieved. Both temperature and internal pressure are maintained for a predeiemiined time, The time may be from about 5 minutes to about 24 hours, such as 10 minutes, 15 minutes, 30 minutes, 45 minutes, 60 minutes. 75 minutes, 90 minutes, 105 minutes, and 120 minutes. j 00401 After the time period in the reactor, the reactor is allowed to cool and the dehydrogenated hydrocarbon product is recovered. The dehydrogenated hydrocarbon products can be recovered by a solvent extraction stage or stages. j 0041 J if necessary, the dehydrogenated hydrocarbon products can be further dehydrogenated b treatment with, one or more polymerisation agents, oxidisers, facilitators, and/or polymer modifiers. These dehydrogenatiori stages can, by variations in pressures, temperatures, residence- times, contact times, and selection of reacting components, produce a variety of required products or special precursors which are amenable to further stages of treatment. The dehyd:rogenation' ^' polymerisation agent or facilitator, ma be selected from one or more of the group consisting of; ferric chloride; ferric oxide calcium chloride; calcium carbonate; lead dioxide; and photolysis.

[0042] The dehydrogenated hydrocarbon products from, the reactor may be fuHereiies or iuHerene precursors or precursors for specialt organic chemicals. j 0043 j Some examples of current syntheses using metallic oxides and dehydrogenation processes, in c mmerc al practice can be fo und in "Catalytic Deliydrogenation of Primary A lcohols" US Patent No. 1 ,975,853, "Dehydrogenation of Methanol for Methyl Formate ¹ ' US Patent Mo. 5,1 4,675, "Oxidative Dehydrogenation of Butane Over Catalyst" Published US Patent Application No. 20140066681) Al . These doc uments disclose the preparation and use of catalysts and they list copper oxide and sine oxide as catalysts among the metallic oxides employed. By definition, a catalyst is a material which promotes a chemical reaction but. remains unchanged at the end of the reaction . The metallic oxides as described i the solid-state dehydrogenation process of the present .disclosure provide a source of oxygen for the dehydrogenation proeess. For example, if copper oxi de is used, it enters the chemical., reaction, it loses its oxygen and it is reduced to copper. It is: clear that the metallic oxides employed in this proeess arc reaetants, not catalysts..

[0044] The dehydrogenatio processes listed above in the examples of prior art allow for progressive withdrawal of hydrogen and/or products under pressure in order to drive the reaction forward., in contrast, in the solid-state dehydrogenatiori proeess described herein, the reaction is carried out in a closed o sealed system and the reactor is closed and the water formed by dehydrogenation: is removed in situ. The product is not removed continuously in the fatter process.

[00451 111 certain embodiments of the process , the oxidising agent is copper oxide and the absorbent is calcium oxide..

[0046] In certai othe embodiments of the proeess, sulphur ca also be used as an oxidant with zinc oxide as the absorbent. In such an arrangement, the sulphur causes the dehydrogenation and hydrogen sulphide i s produced instead of water, The hydrogen sulphide is then acted upon b the zinc oxide to form zinc sulphide and water. The water is then absorbed by the calcium oxide. In thi application, the zinc oxide is a reactani not a catalyst. j 0047 ] Clearly, with temperature, pressure, residence time, and selection of reacting components being in easy control in any particular application, the chemical outcome and cost of operation i s predictable and measureable. This is the hallmark of a satisfactory chemical synthesis under commercial operating conditions. Process control can be made routine and uncomplicated for chemical workers; j 0048 ] Advantageously, most residues from the process have a monetary recovery value. For example, when copper oxide is used and spent, it can be recovered as a secondary product and sold to recyclers of metallic residues or to agricultural chemical manufacturers.

[0049 ] The finding that this proeess can be applied to the production of fullerene hydrides is a testament to its potential use in other arranged dehydrogenations.

[0050] Optionally, a second stage dehydrogenation may be used for precursor extracts, .In this second stage, oxidants can be varied to modif the molecular weight distribution. Suitable oxidants include ferric chloride, ferric oxide, lead dioxide, or exposure to light (i.e. a photolysis polymerisation procedure).

[0051] Commonly:, a liquid chrom tography separation of the various molecular weight fractions which are present is employed to complete the proeess. 10052 J It -will be clear from the preceding discussion that also provided herein is a dehydrogcnated hydrocarbon product formed by the process as described, and a reaction product formed by the process as described.

}0()53 ) As mentioned eariier, researchers workin in the science of hydrogen fuel power are attracted to the possibilities of using fullereiie hydrides because of their abilit to act as storage agents for hydrogen. Work so far indicates that fuiierene hydrides are able to adsorb hydrogen on their surfaces and can be made- to release it when required. The following references are useful in describing the current stage of fuiierene hydride synthesis as at 2013, and 8tt hidication ©.f fuiierene hydrides as potential hydrogen storage materials:

* KharJamov, A et ai. Joint Synthesis of -Small. Carbon Molecules (CrQu), Quasi-FuUerenes (C ₄₀ , C _¾; ¾} and thei Hydrides, Chemical Engineering nd Science, 2013, Vol. 1, No. 3, Pages 32-40;

• Kharlainov, A et el. Mass Spectrometrie -Research of Hydrogcaated Molecules -of Carbon as Products of Pyroiysis of Benzene and Pyridine Vapours , Chemical and Materials Engineering, 2013, Vol. 1, Mo. 4,. Pages 122-131 ; and

« Vehviiainen, T. T. et a!. Hydrogen interactio with fullerenes: From _¾ to grapheme. Physical Review B M, 085447 (201.1 ).

EXAMPLE

[0054] Example 1 - Formation of fuiierene hydrides with catalyst

{ _, 0055 ^' j Reactanfs comprising naphthalene, copper oxide, calcium oxide, and nickel catalyst were weighed close to theoretical amounts as follows

Naphthalene 1 .281) gm

Copper Oxide 3.200 gra

Calcium Oxide 2.240 gm

Nickel 0.365 gm [0056] The reactants were premixed and placed in the reactor which was then closed and sealed. The free volume within the reactor was a value which allowed a maximum pressure of about 45 atmospheres at approximately 300 degrees C calculated on the number of moles of naphthalene available. The temperature was maintained for about 60 minutes and the reactor was the allowed to cool. The reaction mass was removed, ground very fine and the unreacted naphthalene was removed by vacuum processing.

[00571 The reaction mass was then subjected to a 20ml extractio in toluene and it displayed an intense ruby colour. The solids in the extract liquor were separated and set aside to demonstrate- the recovery of their copper content .

[0058] A number of runs as described above were carried out and mass spectra were obtained for Sample (a composite of seven runs) and Sample 10 (a composite, of three runs). O examination of these mass spectra (Figure i } it was observed that :

• The composition of the product from the process conditions outlined above was constant and reliable;

• The deJrydrogenation process performed as expected and demonstrated significant increases i moieeular weights above the original 128; and

• The product/extract as available could be a precursor for further synthesis.

[0059 ] The products/extracts obtained were then subjected to a second stage eh drogenation by contacting them with ferric chloride. Two contact methods were found to be very effective and are described below: fa) In one process, feme chloride was dissolved in a small quantity of methanol and hat solution was incorporated in the toluen extract. After a contact time of fi ve days, the solution was taken to dryness, the ferric chloride was washed out and the residue was redissolve in toluene. This liquor was then ready for liquid chroma tography testing.

( b) in an alternative process, ferric chloride was dissol ved in a small quantity of water and introduced to the toluene extract and shaken mechanically for about six. hours and then allowed to stand for five days. In this method, the aqueous layer changes colour over time: as the ferric chloride

(yellow) is reduced to ierrous chloride (blue) and the resultant .colour shows green. The toluene layer above the aqueous can proceed directly to liquid chromatography testing. [0060] Sample 2 -described above was subjected to the ferric chloride treatment according to method (a) and the resultant liquor was tested b Liquid chromatography. The obvious colour bands were collected separately as Samples 2AI, 2A2, and 2 A3. ^" The- first ^' band to elttte- was Sample 2A1. and it displayed an intense blue fluorescence under ultraviolet light.

[00 1] The mass spectrum (MALDl) for this sample is shown in Figure 2. in the mass spectrum, it can be seen tha Mlerene hydrides are present. The fullerene hydrides lie approximately between 247 and 548 aniu and show the expected periodicity character.

10062] Example 2 - Formation cffittter ne hydrides without catalyst

[0063 ] A further sample (Sample 5) was prepared from composite of two runs with the following average: composition of reactants:

Naphthalene 1.275 gm Copper Oxide 3.273 gm

Calcium Oxide 1.772 gm

[0064] The initial operating pressure was 41 atmospheres, from heating over two stages each with an average temperature o f about 320 degrees C for 15 mm. fte the product was collected a nd the unused naphthalene was removed, it was subjected to an 18ml volume toluene extraction which displayed a low ruby colour. The copper residues were removed and the cleaned ali quot of Sample 5 was then divided as Sample 5A and 5B and each subjected to different secondary treatments, the details of which are below.

[00651 Sample 5A of 5ml was treated with 50 mg of ferric chloride and 1, 5 m l of methanol and shaken for 10 minutes. An amount of 100 mg of calcium carbonate was added and the sample was shaken for a further 10 minutes and set aside for 2 days. After that time the sample was taken to dryness, the ferric chloride washed out and the residue redissolved in toluene. The clean product as. found was presented for mass spectrometry and the spectra are shown in Figure 3.

[0066 ] Sample 5B of 5 nil was treated with 50mg of ferric chloride and 1.5 ml of methanol and shaken for 10 minutes. An amount of 1 mg of lead dioxide wa s adde d and the sample was shaken for a further 10 minutes and then set aside for 2 days. After that time the sample was decanted from: the lead oxide residue and then taken to dryness. The ferric chloride was washed out and the resulting solids were redissolved in toluene. This clean product was highly fluorescent, it was. presented for mass spectrometry as found and the spectra are shown in Figure 4. π

10067 ] It ^■ will be appreciated by those skilled in the art that the invention: is not restricted in its use to the particular application described. Neither is the present invention restricted in its preferred embodiment with regard to the particular elements and/or features described or depicted herein. It will be appreciated that the invention is not limited to the embodiment or embodiments disclosed, but is. capable of nnmero ^' tis rearrangements, modifications and substitutions without departing torn the scope of the invention as set forth and defined by the following claims, j 00681 Throughout the specification and the claims that follow, unless th context requires otherwise, the ords "comprise" and "include" and. variations such, as "comprising" and "including" will be understood to imply the inclusion of a stated integer or group of integers., but not the exclusio of an other integer or group of integers .. j 00691 The reference to any prior art in. this specificati n is not, and should no be taken as, an acknowledgement of any form of suggestion that such prior art forms part of the common general knowledge.