APPARATUS AND METHOD RELATED TO USE OF SYNGAS IN OLEFIN

PRODUCTION

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to and the benefit of U.S. provisional application 62/537,769, filed on July 27, 2017, which is incorporated herein by reference in its entirety.

BACKGROUND

[0002] Syngas (mixtures of H ₂ and CO), also known as synthesis gas, can be readily produced from a carbon source, such as either coal or methane (natural gas) by methods well known in the art and widely commercially practiced around the world. A number of well-known industrial processes use syngas for producing various hydrocarbons and oxygenated organic chemicals.

[0003] The Fischer-Tropsch catalytic process for catalytically producing hydrocarbons from syngas was initially discovered and developed in the 1920 ^' s, and was used in South Africa for many years to produce gasoline range hydrocarbons as automotive fuels. The catalysts typically comprised iron or cobalt supported on alumina or titania, and promoters were sometimes used with cobalt catalysts to improve various aspects of catalytic performance. The products were typically gasoline-range hydrocarbon liquids having six or more carbon atoms, along with other heavier hydrocarbon products.

[0004] Today lower molecular weight C2-C4 hydrocarbons are desired and can be obtained from syngas via the Fischer-Tropsch catalytic process. However, appreciable amounts of undesirable by-products such as methane, ethane and propane can be produced in the Fisher- Tropsch reaction synthesis, thereby reducing yield and efficiency of the process.

[0005] Furthermore, the composition of synthesis gas used in the Fisher-Tropsch olefin production is an important consideration. It is desired to make the Fisher-Tropsch olefin production process energy efficient, while producing a high yield of desired products.

[0006] Accordingly, there remains a long-term market need for a new and improved apparatus and method that utilizing energy and by-products from the Fischer-Tropsch process to improve the energy efficiency and yield of olefin production. Such an apparatus and method are described herein.

SUMMARY OF THE INVENTION

[0007] Disclosed herein is an apparatus comprising: a) a synthesis gas generation unit; b) a first heat exchange cracker, wherein the first heat exchange cracker is in fluid communication with the synthesis gas generation unit; c) a second heat exchange reformer, wherein the second heat exchange reformer is in fluid communication with the synthesis gas generation unit, wherein the second heat exchange reformer is configured in parallel to the first heat exchange cracker; and d) a Fischer-Tropsch reactor, wherein the reactor is in fluid communication with the first heat exchange cracker and the second heat exchange reformer.

[0008] Also disclosed herein is a method comprising the steps of: a) converting a first synthesis gas to a first product comprising methane, ethane, and propane, wherein the converting comprises a Fischer-Tropsch synthesis reaction; b) separating the methane, ethane, and propane from the first product to produce a tail gas comprising methane, a tail gas comprising ethane and propane; and c) subjecting the tail gas comprising ethane and propane to sufficient heat in a first heat exchange cracker, wherein the first heat exchange cracker is configured to receive a first portion of a feed of a second synthesis gas having a temperature of at least 900 °C, and wherein the sufficient heat is provided by heat exchange with the first portion of the second synthesis gas, thereby cracking the ethane and propane to produce ethylene and propylene and cooling the first portion of the second synthesis gas to produce a third synthesis gas having a temperature from about 500 °C to about 900 °C.

[0009] Additional advantages will be set forth in part in the description which follows, and in part will be obvious from the description, or can be learned by practice of the aspects described below. The advantages described below will be realized and attained by means of the chemical compositions, methods, and combinations thereof particularly pointed out in the appended claims. It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention, as claimed. DESCRIPTION OF THE FIGURES

[0010] The accompanying figures, which are incorporated in and constitute a part of this specification, illustrate several aspects, and together with the description, serve to explain the principles of the invention.

[0011] FIGs. 1A and IB show a flow diagram of an exemplary apparatus and an exemplary method described herein.

[0012] FIG. 2 shows schematics of an exemplary first heat exchanger disclosed herein.

[0013] FIG. 3 shows schematics of an exemplary second heat exchanger disclosed herein.

[0014] The present invention can be understood more readily by reference to the following detailed description of the invention.

DETAILED DESCRIPTION

[0015] Disclosed herein are materials, compounds, compositions, and components that can be used for, can be used in conjunction with, can be used in preparation for, or are products of the disclosed method and compositions. It is to be understood that when combinations, subsets, interactions, groups, etc. of these materials are disclosed that while specific reference of each various individual and collective combinations and permutation of these compounds cannot be explicitly disclosed, each is specifically contemplated and described herein. This concept applies to all aspects of this disclosure including, but not limited to, steps in methods of making and using the disclosed compositions. Thus, if there arc a variety of additional steps that can be performed it is understood that each of these additional steps can be performed with any specific aspect or combination of aspects of the disclosed methods, and that each such combination is specifically contemplated and should be considered disclosed.

[0016] All publications mentioned herein are incorporated herein by reference to disclose and describe the methods and/or materials in connection with which the publications are cited.

1. DEFINITIONS

[0017] In this specification and in the claims which follow, reference will be made to a number of terms which shall be defined to have the following meanings: [0018] As used in the specification and in the claims, the term "comprising" can include the aspects "consisting of ¹ and "consisting essentially of." Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. In this specification and in the claims which follow, reference will be made to a number of terms which shall be defined herein.

[0019] As used in the specification and the appended claims, the singular forms "a," "an" and "the" include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to "a hydrocarbon" includes mixtures of two or more hydrocarbons.

[0020] As used herein, the terms "about" and "at or about" mean that the amount or value in question can be the value designated some other value approximately or about the same. It is generally understood, as used herein, that it is the nominal value indicated ±10% variation unless otherwise indicated or inferred. The term is intended to convey that similar values promote equivalent results or effects recited in the claims. That is, it is understood that amounts, sizes, formulations, parameters, and other quantities and characteristics are not and need not be exact, but can be approximate and/or larger or smaller, as desired, reflecting tolerances, conversion factors, rounding off, measurement error and the like, and other factors known to those of skill in the art.

[0021] Ranges can be expressed herein as from "about" one particular value, and/or to "about" another particular value. When such a range is expressed, another aspect includes from the one particular value and/or to the other particular value. Similarly, when values are expressed as approximations, by use of the antecedent "about," it will be understood that the particular value forms another aspect. It will be further understood that the endpoints of each of the ranges are significant both in relation to the other endpoint, and independently of the other endpoint. It is also understood that there are a number of values disclosed herein, and that each value is also herein disclosed as "about ^' " that particular value in addition to the value itself. For example, if the value "10" is disclosed, then "about 10" is also disclosed. It is also understood that each unit between two particular units are also disclosed. For example, if 10 and 15 are disclosed, then 11, 12, 13, and 14 are also disclosed. [0022] The terms "first," "first synthesis gas," "second," "second synthesis gas," and the like, where used herein, do not denote any order, quantity, or importance, and are used to distinguish one element from another, unless specifically stated otherwise.

[0023] As used herein, the terms "optional" or "optionally" means that the subsequently described event or circumstance can or cannot occur, and that the description includes instances where said event or circumstance occurs and instances where it does not.

[0024] References in the specification and concluding claims to parts by weight, of a particular element or component in a composition or article, denote the weight relationship between the element or component and any other elements or components in the composition or article for which a part by weight is expressed. Thus, in a compound containing 2 parts by weight of component X and S parts by weight of component Y, X and Y are present at a weight ratio of 2:5, and are present in such a ratio regardless of whether additional components are contained in the compound.

[0025] A weight percent ("wt %") of a component, unless specifically stated to the contrary, is based on the total weight of the formulation or composition in which the component is included. For example, if a particular element or component in a composition or article is said to have about 80% by weight, it is understood that this percentage is relative to a total compositional percentage of 100% by weight.

[0026] As used herein, the terms "syngas" or "synthesis gas" are used interchangeably herein.

[0027] As used herein, the terms "cracking" and "steam cracking" are used interchangeably herein.

[0028] Moreover, it is to be understood that unless otherwise expressly stated, it is in no way intended that any method set forth herein be construed as requiring that its steps be performed in a specific order. Accordingly, where a method claim does not actually recite an order to be followed by its steps or it is not otherwise specifically stated in the claims or descriptions that the steps are to be limited to a specific order, it is no way intended that an order be inferred, in any respect. This holds for any possible non-express basis for interpretation, including:

matters of logic with respect to arrangement of steps or operational flow; plain meaning derived from grammatical organization or punctuation; and the number or type of aspects described in the specification. 2. APPARATUS

[0029] In a hydrocarbon production process using Fischer Tropsch synthesis, a range of hydrocarbons are produced. The distribution of the range of hydrocarbons produced in a Fischer Tropsch reaction follows the Anderson Schultz Flury product distribution. The hydrocarbons produced include, for example, C1-C3 paraffins, such as methane, ethane and propane, C2-C3 olefins (ethylene and propylene), C4+ hydrocarbons, and wax (i.e. C20+ hydrocarbons). The light paraffins, such as methane, ethane and propane, are conventionally routed to a fuel system, which results in an overall low yield of ethylene and propylene.

Disclosed herein are an apparatus and a method that utilize a Fischer Tropsch based process to maximize the production of ethylene and propylene by having the capabilities to increase the overall yield of ethylene and propylene by converting ethane and propane to ethylene and propylene in an energy efficient manner. The apparatus and a method disclosed herein also have the capabilities of simultaneously reforming methane to synthesis gas in an energy efficient manner.

[0030] Conventionally ethylene and propylene are produced by steam cracking of ethane, propane, and naphtha. Other feedstocks have been sought for, for the production of ethylene and propylene. As described above, ethylene and propylene can also be produced from synthesis gas via Fischer Tropsch synthesis. The synthesis gas can be produced from carbon containing sources such as natural gas, coal, biomass and liquid hydrocarbon feedstocks. In this process the carbonaceous feed is first converted into synthesis gas. After cooling and cleaning of the synthesis gas, the CO and H ₂ are converted to hydrocarbons via Fischer Tropsch synthesis. Ethylene and propylene are then recovered from the Fischer Tropsch synthesis products. Methane, ethane, and propane are amongst other products formed via the Fischer Tropsch reaction, and are separated when ethylene and propylene are recovered. Ethane and propane can directly be converted to ethylene and propylene, while methane can be reformed to syngas that can be used to produce further products including ethylene and propylene.

[0031] The feed of carbonaceous containing material is converted to synthesis gas at a temperature above at least about 900 °C . The resulting synthesis gas also has a temperature above at least 900 °C. This synthesis gas needs to be cooled before it is used in a Fischer- Tropsch reaction, which usually operates at a temperature from about 220 °C to about 380 °C, such as from about 220 °C to about 270 °C. In a conventional syngas generation unit, the synthesis gas with a temperature above at least about 900 °C is cooled in a steam generating unit, which produces steam that can be used in various processes.

[0032] The apparatus and method disclosed herein utilize the heat from the synthesis gas with a temperature above at least about 900 °C to drive the cracking process of ethane and propane to produce ethylene and propylene. The apparatus and method disclosed herein can also simultaneously utilize the heat from the synthesis gas with a temperature above at least about 900 °C to drive the reformation process of methane to produce new synthesis gas, which in turn can be used to produce more ethylene and propylene in a Fischer Tropsch reaction.

Accordingly, the synthesis gas can be cooled by converting methane to synthesis gas and by converting ethane and propane directly to ethylene and propylene.

[0033] Thus, the apparatus and method disclosed herein are more energy efficient than a conventional syngas process, since the energy in the synthesis gas having a temperature above at least about 900 °C is used to drive chemical reactions instead of only generating steam.

[0034] Accordingly, disclosed herein is an apparatus comprising: a) a synthesis gas generation unit; b) a first heat exchange cracker, wherein the first heat exchange cracker is in fluid communication with the synthesis gas generation unit; c) a second heat exchange reformer, wherein the second heat exchange reformer is in fluid communication with the synthesis gas generation unit, wherein the second heat exchange reformer is configured in parallel to the first heat exchange cracker; and d) a Fischer-Tropsch reactor, wherein the reactor is in fluid communication with the first heat exchange cracker and the second heat exchange reformer.

[0035] In one aspect, the apparatus further comprises a first heat recovery and a steam generation unit that is in fluid communication with the first heat exchange cracker and the Fischer-Tropsch reactor.

[0036] In one aspect, the apparatus further comprises a second heat recovery and a steam generation unit that is in fluid communication with the second heat exchange reformer and the Fischer-Tropsch reactor. [0037] In one aspect, the apparatus further comprises an acid gas removal unit that is in fluid communication with the first heat exchange cracker, the second heat exchange reformer, and the Fischer-Tropsch reactor.

[0038] The syngas generation unit is configured to receive a carbon source, for example, natural gas, that can be converted to syngas in the syngas generation unit. It is understood that the syngas can be generated from a variety of different materials that contain carbon. In some aspects, the syngas can be generated from biomass, plastics, coal, municipal waste, natural gas, or any combination thereof. In yet other aspects, the syngas can be generated from a fuel comprising methane. In some other aspects, the syngas generation from the fuel comprising methane can be based on steam reforming, autothermal reforming, or a partial oxidation, or any combination thereof. Accordingly, the syngas generation unit can be a steam reforming syngas generation unit, an autothermal syngas generation unit, or a partial oxidation syngas generation unit. In some aspects, the syngas is generated by steam reforming. In these aspects, steam methane (natural gas) reforming uses an external source of hot gas to heat tubes in which a catalytic reaction takes place that converts steam and methane into a gas comprising hydrogen and carbon monoxide. In other aspects, the syngas is generated by autothermal reforming. In these aspects, methane is partially oxidized in a presence of oxygen and carbon dioxide or steam. In aspects where oxygen and carbon dioxide are used to generate syngas from methane, the hydrogen and carbon monoxide can be produced in a ratio of 1 to 1. In some aspects, where oxygen and steam are utilized, the hydrogen and carbon monoxide can be produced in a ratio of 2.5 to 1. In some other aspects, the syngas is generated by a partial oxidation. In these other aspects, a substoichiometric fuel-air mixture is partially combusted in a syngas generation unit, creating a hydrogen-rich syngas. In a certain aspect, the partial oxidation can comprise a thermal partial oxidation and catalytic partial oxidation. In some aspects, the thermal partial oxidation is dependent on the air-fuel ratio and proceed at temperatures of 1,200 °C or higher. It is further understood that the choice of a reforming technique can depend on the sulfur content of the fuel being used. The catalytic partial oxidation can be employed if the sulfur content is below 50 ppm. A higher sulfur content can contaminate the catalyst, and thus, other reforming techniques can be utilized.

[0039] The carbonaceous feed together with oxygen and steam is converted to synthesis gas at a temperature not less than 900 °C in the synthesis gas generation unit. The syngas that that is produced in the synthesis gas generation unit can have a H ₂ /CO molar ratio from about 0.5 to about 5. In some exemplary aspects, the H ₂ /CO molar ratio can be from about 1.0 to about 3.0. In other exemplary aspects, the H ₂ /CO molar ratio can be from about 1.5 to about 3.0, or in yet further exemplary aspects, the H ₂ /CO molar ratio can be from about 1.5 to about 2.5. It will be appreciated that the H ₂ /CO molar ratio can control the selectivity of the hydrocarbons that are being produced in the reactor where synthesis gas is converted to hydrocarbons. The H ₂ and CO (i.e. synthesis gas) are catalytically reacted in the reactor downstream.

[0040] The Fisher Tropsch reactor of the disclosed apparatus is in fluid communication with the first and the second heat exchange reformers. In some aspects, any of the heat exchanger units disclosed herein can comprise one or more heat exchanger units. In other aspects, any of the heat exchanger units disclosed herein can comprise at least two heat exchanger units. It is further understood that the term "heat exchanger unit," as used herein, refers to any unit built for efficient heat transfer from one medium to another. In some aspects, the media can be separated by a solid wall to prevent mixing. It is further understood that the heat exchanger units can be classified according to their flow arrangements. In the aspects, where two mediums enter the exchanger at the same end, and travel in parallel to one another to the other side, the heat exchanger unit is classified as parallel-flow heat exchanger. In the aspects, where two mediums enter the exchanger from opposite ends is classified as a counter-flow heat exchanger unit. In the aspects, wherein two fluids travel perpendicular to one another through the exchange, the heat exchanger unit is classified as a cross-flow heat exchanger.

[0041] In one aspect, the second heat exchange unit is a steam reformer utilizing the sensible heat of the second portion of the second synthesis gas to drive the endothermic steam reforming reaction of converting methane to synthesis gas in the presence of a catalyst and steam.

[0042] It is further understood that any known in the art Fischer-Tropsch reactor can be used. In some aspects, isothermal and/or adiabatic fixed bed reactors can be used as a Fischer- Tropsch reactor, which can carry out the Fischer-Tropsch process. The Fischer-Tropsch reactor can comprise a catalyst, such as, for example, one or more Fischer-Tropsch catalysts. Fischer-Tropsch catalysts are known in the art and can, for example, be Fe based catalysts and/or Co based catalysts and/or Ru based catalysts. In one aspect, the reactor comprises a Co/Mn catalyst or a Co/Mo catalyst, or a combination thereof. For example, U.S. patent 9,416,067 discloses a promoted Co/Mn catalyst for use in a Fischer-Tropsch process, which is hereby incorporated in its entirety, specifically for its disclosure of a promoted Co/Mn catalyst. For example, U.S. patent 9,381,499 discloses a supported Co/Mo catalyst for use in a Fischer- Tropsch process, which is hereby incorporated in its entirety, specifically for its disclosure of a supported Co/Mo catalyst.

[0043] The first heat exchanger disclosed herein is configured to crack propane and ethane to ethylene and propylene. In one aspect, the first heat exchanger is a cracker. An exemplary configuration of the first heat exchange cracker is shown in FIG. 2.

[0044] The second heat exchanger disclosed herein is configured to reform methane to synthesis gas. In one aspect, the second heat exchanger is a reformer. An exemplary configuration of the second heat exchange reformer is shown in FIG. 3. In one aspect, the second heat exchanger comprises a catalyst. Suitable catalysts are known in the art, and can be nickel based catalysts, which are typically supported on an alumina support or a magnesium alumina spindel support. For example, nickel based catalysts are described in U.S. 6,852,668 by de Lasa, and is hereby incorporated by reference in its entirety, specifically for the disclosure related to nickel based catalysts.

[0045] Optionally, in various aspects, the disclosed system can be operated or configured on an industrial scale. In one aspect, the reactors described herein can each be an industrial size reactor. For example the synthesis gas generation unit can be an industrial size reactor. In yet another example, the Fischer-Tropsch reactor can be an industrial size reactor. For example, the first heat exchange cracker, the second heat exchange reformer, and/or the third heat exchanger unit can be an industrial size reactor.

[0046] The reactors, units, and vessels disclosed herein can have a volume of at least about 1,000 liters, about 2,000 liters, about 5,000 liters, or about 20,000 liters. For example, the reactor can have a volume from about 1,000 liter to about 20,000 liters.

[0047] In one aspect, the synthesis gas generation unit can have a volume of at least about 1,000 liters, about 2,000 liters, about 5,000 liters, or about 20,000 liters. For example, the synthesis gas generation unit can have a volume from about 1,000 liter to about 20,000 liters. [0048] In one aspect, the Fischer-Tropsch reactor can have a volume of at least about 1 ,000 liters, about 2,000 liters, about 5,000 liters, or about 20,000 liters. For example, the Fischer- Tropsch reactor can have a volume from about 1,000 liter to about 20,000 liters.

[0049] In one aspect, the first heat exchange cracker, the second heat exchange reformer, and/or the third heat exchanger unit can have a volume of at least about 1,000 liters, about 2,000 liters, about 5,000 liters, or about 20,000 liters. For example, the first heat exchange cracker, the second heat exchange reformer, and/or the third heat exchanger unit can have a volume from about 1,000 liter to about 20,000 liters.

[0050] Now referring to FIGs. 1A and IB, which show a non-limiting exemplary aspect of the apparatus and method disclosed herein. FIG. IB is a simplified version of FIG. 1A. FIGs. 1A and IB show an apparatus 100. The apparatus has a synthesis gas generation unit 102 for converting a carbon source to synthesis gas (a second synthesis gas), for example a coal gasifier unit. For gaseous or liquid feedstocks, the process for synthesis gas generation can utilize a catalyzed syngas generator or an uncatalyzed syngas generator. An example of a catalyzed syngas generator is an Auto Thermal Reformer (ATR), whilst an example of an uncatalyzed syngas generator is a partial oxidation (POX) reactor or gasifier. In the case an ATR is used for syngas generation, desulfurization of the feedstock takes place upstream of this synthesis gas generator and hence hydrogen is required for this purpose. Therefore the hydrogen stream to the synthesis gas generation unit is indicated as a dashed line in FIG. 1, since it is required only if a catalyzed synthesis gas generator is used. If a catalyzed synthesis gas generator is used, desulfurization of the feedstock takes place within the synthesis gas generation unit 102, and then the Acid Gas Removal Unit 112 upstream of the Fischer-Tropsch reactor 114 is not required, since the contaminates for the Fischer-Tropsch catalyst have been removed in the synthesis gas generation unit 102. Therefore the acid gas removal unit 112 is indicated as a dashed block, because it will be omitted if a catalyzed synthesis gas generator is utilized. The recycle of carbon dioxide to the synthesis gas generation unit 102 is optional and can be used as a lever to manipulate the H ₂ /CO from the synthesis gas generation unit 102. This is the reason why it is indicated as a dashed line in FIG. 1A.

[0051] The synthesis gas generation unit 102 is in fluid communication with the first heat exchange cracker 106. The synthesis gas generation unit 102 can also be in fluid

communication with the second heat exchange reformer 104. The second synthesis gas that is generated in the synthesis gas generation unit 102 has a temperature of at least about 900 °C and is divided into a first portion of the second synthesis gas and a second portion of the second synthesis gas. The first portion of the second synthesis gas is directed to the first heat exchange cracker 106. The second portion of the second synthesis gas is directed to the second heat exchange reformer 104. The first heat exchange cracker 106 and the second heat exchange reformer 104 are arranged parallel to each other relative to the synthesis gas generation unit 102. The first heat exchange cracker 106 and the second heat exchange reformer 104 are also in fluid communication with a Fischer-Tropsch reactor 114. The apparatus 100 can also contain a first heat recovery' and a steam generation unit 110 that is in fluid communication with the first heat exchange cracker 106 and the Fischer-Tropsch reactor 114. The apparatus 100 can also contain a second heat recovers' and a steam generation unit 108 that is in fluid communication with the second heat exchange reformer 104 and the Fischer-Tropsch reactor 114. Thus, the first portion of the second synthesis gas flows through the first heat exchange cracker 106 and the first heat recover}' and a steam generation unit 110. The temperature of the first portion of the second synthesis gas is reduced at each stage finally producing a fifth synthesis gas having a temperature from about 30 °C to about 270 °C. The fifth synthesis gas can have a temperature from about 30 °C to about 100 °C if the fifth synthesis gas is to be processed in the acid gas removal unit 112. The fifth synthesis gas can have a temperature from about 150 °C to about 270 °C if the fifth synthesis gas is not to be processed in the acid gas removal unit 112. The second portion of the second synthesis gas flows through the second heat exchange reformer 104 and the second heat recover}' and a steam generation unit 108. The temperature of the second portion of the second synthesis gas is reduced at each stage finally producing a sixth synthesis gas having a temperature from about 30 °C to about 270 °C. The fifth synthesis gas can have a temperature from about 30 °C to about 100 °C if the sixfth synthesis gas is to be processed in the acid gas removal unit 112. The fifth synthesis gas can have a temperature from about 150 °C to about 270 °C if the sixth synthesis gas is not to be processed in the acid gas removal unit 112. Both the first heat recovery and a steam generation unit 110 and the second heat recovery and a steam generation unit 108 are in fluid communication with an acid gas removal unit 112. The fifth and the sixth synthesis gases are combined before entering the acid gas removal unit 112 to produce a seventh synthesis gas. The acid gas removal unit 112 is in further fluid communication with the Fischer-Tropsch reactor 114. C0 ₂ is removed from the seventh synthesis gas in the acid gas removal unit 112 to produce the first synthesis gas that can be used to produce the first product comprising methane, ethane, and propane. The Fischer-Tropsch reactor 114 is in further fluid communication with the Fisher-Tropsch (FT) Gas C0 ₂ removal and FT Gas Dryer unit 118 and Olefin Rich Gas dryer unit 118. The FT reactor 114 is in further fluid

communication with Olefin conversion unit 116. The FT gas C0 ₂ removal and FT gas dryer unit 118 and Olefin Rich Gas dryer unit 118 are in fluid communication with the Light Ends Recovery 128 and Pressure Swing Adsorption unit 128. The Light Ends Recovery unit 128 separates methane from unconverted syngas and other products, thereby forming a tail gas comprising methane. The Light Ends Recovery 128 and Pressure Swing Adsorption unit 128 is further in fluid communication with a product separation unit 122 where a product stream comprising ethylene and propylene is formed and a tail gas comprising ethane and propane are formed. The olefin conversion unit 116 is in fluid communication with an aromatics extraction unit 124.

3. METHODS

[0052] Disclosed herein is a method comprising the steps of: a) converting a first synthesis gas to a first product comprising methane, ethane, and propane, wherein the converting comprises a Fischer-Tropsch synthesis reaction; b) separating the methane, ethane, and propane from the first product to produce a tail gas comprising methane, a tail gas comprising ethane and propane; and c) subjecting the tail gas comprising ethane and propane to sufficient heat in a first heat exchange cracker, wherein the first heat exchange cracker is configured to receive a first portion of a feed of a second synthesis gas having a temperature of at least 900 °C, and wherein the sufficient heat is provided by heat exchange with the first portion of the second synthesis gas, thereby cracking the ethane and propane to produce ethylene and propylene and cooling the first portion of the second synthesis gas to produce a third synthesis gas having a temperature from about 500 °C to about 900 °C.

[0053] In one aspect, step b) can be performed, in part, by cooling the first product to achieve separation of components, which is followed by physical absorption to remove C0 ₂ , which can followed by cryogenic and conventional distillation to produce a tail gas comprising methane, a tail gas comprising ethane and propane [0054] In one aspect, the method further comprises the step of subjecting the tail gas comprising methane to a sufficient heat in a second heat exchange reformer, thereby producing a reformed gas comprising synthesis gas, wherein the heat is provided by heat exchange with a second portion of the second synthesis gas, thereby cooling the second portion of the second synthesis gas to produce a fourth synthesis gas having a temperature from about 500 °C to about 900 °C.

[0055] In one aspect, the method disclosed herein can be performed by the apparatus disclosed herein. In the exemplary aspect, the method disclosed herein is schematically illustrated in FIG 1.

[0056] In one aspect, the Fischer-Tropsch synthesis reaction can be performed with a Fischer- Tropsch catalyst, for example, Fe based catalysts and/or Co based catalysts and/or Ru based catalysts. In one aspect, Fischer-Tropsch synthesis reaction can be performed with a Co/Mn catalyst or a Co/Mo catalyst, or a combination thereof.

[0057] In some aspects, the first synthesis gas has a composition comprising a ratio of H ₂ to CO from about 1.0 to about 2.0, including exemplary values of about 1.1, about 1.2, about 1.3, about 1.4, about 1.5, about 1.6, about 1.7, about 1.8, and about 1.9. In yet other aspects, the first synthesis gas has a temperature from about 220 °C to about 270 °C, including exemplary values of about 230 °C, about 240 °C, about 250 °C, and about 260 °C.

[0058] The first product is produced in a Fischer-Tropsch reactor 114. The methane, ethane, and propane are separated from the first product to produce a tail gas comprising methane, and a tail gas comprising ethane and propane. It is understood that the tail gas comprising ethane and propane can be a two separate tail gases, one tail gas with ethane, and one tail gas with propane, or one single tail gas comprising both ethane and propane.

[0059] The Fischer-Tropsch catalytic process for producing hydrocarbons from synthesis is known in the art. Several reactions can take place in a Fischer-Tropsch process, such as, a Fischer-Tropsch (FT) reaction, a water gas shift reaction, and a hydrogen methanation, as shown in Scheme 1.

[0060] A Fischer-Tropsch process that targets the production of light olefins (C2-C8 olefins) is desired and such process can produce a significant amount of C2-C3 hydrocarbons. In other aspects, the FT process can further comprise a product stream comprising C2-C3, C3+ olefins, or any combination thereof. It is further understood that the product stream comprising methane, ethane and propane is also formed. In other aspects, the desirable olefins are separated and the tail gases comprising methane, ethane and propane are formed.

[0061] The tail gas comprising ethane and propane is introduced into the first heat exchange cracker 106. The first heat exchange cracker 106 is configured to crack the ethane and propane to ethylene and propylene. The cracked gas from the ethane can be further processed in an olefin conversion unit 116. In the olefin conversion unit 116, a catalytic cracker is employed which converts the hydrocarbon condensate and oxygenates from the Fischer-Tropsch reactor 114 into to ethylene and propylene. The olefin conversion unit 116 includes a compressor and caustic wash section, and it is for this reason that the cracked gas from the ethane and propane cracker is routed to the olefin conversion unit 116. The cracked gas from the ethane and propane cracker bypasses the catalytic cracker in the olefin conversion unit 116 and is combined with the product gas from the catalytic cracker upstream of the compressor. The cracked gas from the ethane and propane cracker may contain sulfur and therefore it is not routed directly to the product separation unit 122. The caustic wash in the olefin conversion unit 116 will remove the sulfur and C0 ₂ in the cracked gas from both the catalytic cracker and ethane and propane cracker. The olefin rich gas from the olefin conversion unit 116 is processed in a dryer before separation takes place.

[0062] The tail gas comprising methane is introduced into the second heat exchange reformer 104. The second heat exchange reformer 104 is configured to reform methane to synthesis gas. [0063] The energy (i.e. heat) that is needed to perform the chemical reactions in the first heat exchange cracker 106 and the second heat exchange reformer 104 is provided from a second synthesis gas that has been generated by the synthesis gas generation unit 102. The second synthesis gas has a temperature of at least about 900 °C. The second synthesis gas can have a temperature of at least about 900 °C, at least about 950 °C, at least about 1,000 °C, at least about 1,100 °C, at least about 1,200 °C, at least about 1,300 °C, at least about 1,400 °C, or at least about 1,500 °C. For example the second synthesis gas can have a temperature from about 900 °C to about 1,600 °C,

[0064] In one aspect, the second synthesis gas is generated from a solid carbon containing feed. It is understood that the second syngas can be generated from a variety of different sources that contain carbon. In some aspects, the syngas can be generated from biomass, plastics, coal, municipal waste, natural gas, or any combination thereof.

[0065] In one aspect, method further comprises the step of producing the second synthesis gas in a syngas generation unit, wherein the first heat exchange cracker and the second heat exchange reformer are arranged in parallel to the syngas generation unit.

[0066] A first portion of the second synthesis gas enters the first heat exchange cracker 106 to exchange heat with tail gas comprising ethane and propane. Ethane and propane are cracked and the first portion of the second synthesis is cooled to produce a third synthesis gas having a temperature from about 500 °C to about 900 °C during this process.

[0067] A second portion of the second synthesis gas enters the second heat exchange reformer 104 to exchange heat with tail gas comprising methane. Methane is reformed in the presence of a catalyst and the second portion of the second synthesis is cooled to produce a fourth synthesis gas having a temperature from about 500 °C to about 900 °C during this process.

[0068] In one aspect, the method further comprises the step of producing steam in a first heat recovery and steam generation unit, wherein the steam is produced by heat exchange with the third synthesis gas, thereby cooling the third synthesis gas to produce a fifth synthesis gas having a temperature from about 30 °C to about 270 °C, such as from about 30 °C to about 100 °C, or from about 150 °C to about 270 °C. The first heat recovery and steam generation unit 110 operates by heat exchange with the third synthesis gas. In one aspect, the steam generated in the first heat recovery and steam generation unit 110 can be fed back for use in the first heat exchange cracker 106 and/or the second heat exchange reformer 104. In yet other aspects, the steam formed in the first heat recovery and steam generation unit 110 and fed back to the second heat exchange reformer 104 can be used as a reactant in reforming of the tail gas comprising methane.

[0069] In another aspect, the method further comprises the step of producing steam in a second heat recover^' and steam generation unit, wherein the steam is produced by heat exchange with the fourth synthesis gas, thereby cooling the fourth synthesis gas to produce a sixth synthesis gas having a temperature from about 30 °C to about 270 °C, such as from 30 °C to 100 °C, or from 150 °C to 270 °C. The second heat recovery and steam generation unit 108 operates by heat exchange with the fourth synthesis gas. In one aspect, the steam generated in the second heat recovery and steam generation unit 108 can be fed back for use in the first heat exchange cracker 106 and/or the second heat exchange reformer 104. In yet other aspects, the steam formed in the second heat recovery and steam generation unit 108 and fed back to the second heat exchange reformer 104 can be used as a reactant in reforming of the tail gas comprising methane.

[0070] In one aspect, the method further comprises combining the fifth synthesis gas and the sixth synthesis gas to produce a seventh synthesis gas. The seventh synthesis gas can further comprises the reformed gas comprising synthesis gas that is produced in the second heat exchange reformer 104. At least a portion of the seventh synthesis gas originates from the second synthesis gas, which is generated in the synthesis gas generation unit and also contains C0 ₂ . Thus, the seventh synthesis gas also contains C0 ₂ . In one aspect, the second synthesis gas and/or seventh synthesis gas comprises up to 20 wt % of C0 ₂ . For example, the second synthesis gas and/or seventh synthesis gas can comprise from 1 wt % to 20 wt % of C0 ₂ , such as, from 5 wt % to 15 wt % of C0 ₂ . The C0 ₂ can be classified as acid gas.

[0071] In one aspect, the method further comprises removing acid gas from the seventh synthesis gas, thereby producing the first synthesis gas. The process of removing the acid gas (i.e. C0 ₂ ) from the seventh synthesis gas can be done in an acid gas absorber 112.

[0072] Accordingly, in one aspect, the method disclosed herein can be performed continuous wherein the first synthesis gas generated from the seventh synthesis gas, and can be used to produce the first product comprising methane, ethane, and propane. The seventh synthesis gas originates from the second synthesis gas, which can be produced continuously in the synthesis gas generation unit 102. In another aspect, the method further comprises repeating steps a)-c) one or more times.

[0073] In one aspect, the second synthesis gas having a temperature of at least about 900 °C is generated in a syngas generation unit 102. As described above, it is understood that the syngas can be generated from a variety of different sources that contain carbon.

[0074] The process of removing C0 ₂ from the first product in a first acid gas absorber is described elsewhere herein.

[0075] In one aspect, step c) further comprises contacting the second product comprising syngas with a metal based catalyst, such as for example a Co/Mn catalyst, thereby converting the second product comprising syngas to the third product comprising hydrocarbon product and C0 ₂ .

[0076] A Fischer-Tropsch reactor that targets the production of light olefins (C2-C8 olefins) is desired and such process can produce a significant amount of C2-C3 hydrocarbons, and methane. In some exemplary aspects, the first product can comprise hydrogen, CO, C0 ₂ , methane, ethylene, ethane, propylene, propane, butene, butane, mixture of nitrogen and argon, C2-C7 hydrocarbons, or any combination thereof. An exemplary non-limiting composition of the first product is shown in Table 1. The values shown in Table 1 were simulated using Aspen HYSYS V8.4. The values in Table 1 of the first product were calculated after removal of C0 ₂ and upgrade of C4-C9 hydrocarbons (olefins) via a catalytic conversion unit before being integrated with the remainder of the apparatus disclosed herein.

TABLE 1

4. ASPECTS

[0077] In view of the described catalyst and catalyst compositions and methods and variations thereof, herein below are described certain more particularly described aspects of the inventions. These particularly recited aspects should not however be interpreted to have any limiting effect on any different claims containing different or more general teachings described herein, or that the "particular" aspects are somehow limited in some way other than the inherent meanings of the language and formulas literally used therein.

[0078] Aspect 1 : A method comprising the steps of: a) converting a first synthesis gas to a first product comprising methane, ethane, and propane, wherein the converting comprises a Fischer- Tropsch synthesis reaction; b) separating the methane, ethane, and propane from the first product to produce a tail gas comprising methane, and a tail gas comprising ethane and propane; and c) subjecting the tail gas comprising ethane and propane to sufficient heat in a first heat exchange cracker, wherein the first heat exchange cracker is configured to receive a first portion of a feed of a second synthesis gas having a temperature of at least 900 °C, and wherein the sufficient heat is provided by heat exchange with the first portion of the second synthesis gas, thereby cracking the ethane and propane to produce ethylene and propylene and cooling the first portion of the second synthesis gas to produce a third synthesis gas having a temperature from about 500 °C to about 900 °C.

[0079] Aspect 2: The method of aspect 1, wherein the method further comprises the step of subjecting the tail gas comprising methane to a sufficient heat in a second heat exchange reformer, thereby producing a reformed gas comprising synthesis gas, wherein the heat is provided by heat exchange with a second portion of the second synthesis gas, thereby cooling the second portion of the second synthesis gas to produce a fourth synthesis gas having a temperature from about 500 °C to about 900 °C.

[0080] Aspect 3: The method of aspect 2, wherein method further comprises the step of producing the second synthesis gas in a syngas generation unit, wherein the first heat exchange cracker and the second heat exchange reformer are arranged in parallel to the syngas generation unit.

[0081] Aspect 4: The method of any one of aspects 2-3, wherein the second heat exchange reformer comprises a catalyst. [0082] Aspect 5: The method of any one of aspects 1-4, wherein method further comprises the step of producing steam in a first heat recovery and steam generation unit, wherein the steam is produced by heat exchange with the third synthesis gas, thereby cooling the third synthesis gas to produce a fifth synthesis gas having a temperature from about 50 °C to about 100 °C.

[0083] Aspect 6: The method of any one of aspects 1-5, wherein method further comprises the step of producing steam in a second heat recovery and steam generation unit, wherein the steam is produced by heat exchange with the fourth synthesis gas, thereby cooling the fourth synthesis gas to produce a sixth synthesis gas having a temperature from about 50 °C to about 100 °C.

[0084] Aspect 7: The method of aspects 5 or 6, wherein the method further comprises the step of introducing the steam generated in the first heat recovery and steam generation unit into the first heat exchange cracker or the second heat exchange reformer or bom.

[0085] Aspect 8: The method of aspects 6 or 7, wherein the method further comprises the step of introducing the steam generated in the second heat recovery and steam generation unit into the first heat exchange cracker or the second heat exchange reformer or bom.

[0086] Aspect 9: The method of any one of aspects 6-9, wherein the method further comprises combining the fifth synthesis gas and the sixth synthesis gas to produce a seventh synthesis gas.

[0087] Aspect 10: The method of aspect 9, wherein the seventh synthesis gas comprises the reformed gas comprising synthesis gas.

[0088] Aspect 11 : The method of aspects 9 or 10, wherein the method further comprises removing acid gas from the seventh synthesis gas, thereby producing the first synthesis gas.

[0089] Aspect 12: The method of aspect 11, wherein the method further comprises repeating steps a)-c) one or more times.

[0090] Aspect 13: The method of any one of aspects 1-12, wherein the second synthesis gas is generated from a solid carbon containing feed.

[0091] Aspect 14: The method of any one of aspects 1-13, wherein the Fischer-Tropsch synthesis reaction is performed using a Co-based catalyst. [0092] Aspect 15: The method of any one of aspects 1-14, wherein the second synthesis gas comprises H ₂ and CO in a ratio of H ₂ :CO from about 0.3 to about 1.0.

[0093] Aspect 16: An apparatus comprising: a) a synthesis gas generation unit; b) a first heat exchange cracker, wherein the first heat exchange cracker is in fluid communication with the synthesis gas generation unit; c) a second heat exchange reformer, wherein the second heat exchange reformer is in fluid communication with the synthesis gas generation unit, wherein the second heat exchange reformer is configured in parallel to the first heat exchange cracker; and d) a Fischer-Tropsch reactor, wherein the reactor is in fluid communication with the first heat exchange cracker and the second heat exchange reformer.

[0094] Aspect 17: The apparatus of aspect 16, wherein the apparatus further comprises a first heat recovery and a steam generation unit that is in fluid communication with the first heat exchange cracker and the Fischer-Tropsch reactor.

[0095] Aspect 18: The apparatus of aspects 16 or 17, wherein the apparatus further comprises a second heat recovery and a steam generation unit that is in fluid communication with the second heat exchange reformer and the Fischer-Tropsch reactor.

[0096] Aspect 19: The apparatus of any one of aspects 16-18, wherein the apparatus further comprises an acid gas removal unit that is in fluid communication with the first heat exchange cracker, the second heat exchange reformer, and the Fischer-Tropsch reactor.

[0097] Aspect 20: The apparatus of any one of aspects 16-20, wherein the second heat exchanger cracker comprises a catalyst.

[0098] Various modifications and variations can be made to the compounds, composites, kits, articles, devices, compositions, and methods described herein. Other aspects of the compounds, composites, kits, articles, devices, compositions, and methods described herein will be apparent from consideration of the specification and practice of the compounds, composites, kits, articles, devices, compositions, and methods disclosed herein. It is intended that the specification and examples be considered as exemplary.