Process for producing methanol and hydrogen from methane using solid metal hydroxide reactants

Abstract

The present invention relates to a process for producing methanol (MeOH) and hydrogen (H2) from methane, comprising the steps of: a) providing a gaseous feed stream comprising methane; b) reacting the gaseous feed stream with at least one halogen reactant (X2) under reaction conditions effective to produce an effluent stream comprising methyl halide (MeX), hydrogen halide (HX); c) separating the following from the effluent stream obtained in step b): (i) a methyl halide (MeX) stream, optionally comprising unreacted methane; and, (ii) a hydrogen halide (HX) stream; d) reacting the methyl halide (MeX) stream separated in step c) with a solid metal hydroxide (MOH (s)) under reaction conditions effective to produce metal halide (MX) and methanol (MeOH); and e) decomposing the hydrogen halide (HX) stream separated in step c) by electrolysis under conditions effective to produce a gaseous hydrogen (H2) stream and a stream comprising halogen reactants (X2).

Description

Technical Field

[0001] The present invention generally relates to processes and systems for producing methanol. In particular, the present invention relates to processes and systems for producing methanol and hydrogen from a gas stream comprising or consisting of methane. The process is particularly characterized in that it utilizes a solid metal hydroxide reactant to form methanol and that it uses electrolysis to produce hydrogen gas. Background Art

[0002] Methanol is a key starting material for producing basic chemicals such as formaldehyde, acetic acid, hydrocarbons (hydrocarbons), olefins, biodiesel, gasoline and gasoline additives such as methyl tertiary butyl ether. Methanol can also be used as a transportation fuel, a fuel cell hydrogen carrier and for wastewater treatment or power generation. Therefore, it is a superior fuel and a key starting material for important industrial reactions. In recent years, methanol has also been considered as a substitute for chemical energy carriers.

[0003] Conventionally, methanol (CH 3 OH or MeOH), the synthesis gas is H 2 , CO and CO 2 A combination of hydrogen (H 2 The catalytic conversion of 2-nitrogen (2-nitrogen) and carbon monoxide (CO) from coal-derived synthesis gas to methanol involves the following reactions:

[0004]

[0005]

[0006]

[0007] The catalytic system used for methanol synthesis is typically a mixture of copper, zinc oxide, aluminum oxide, and magnesium oxide.

[0008] All three reactions given above are highly exothermic. In particular, in order to favor the formation of methanol, high pressure and / or high temperature are required to shift the equilibrium towards methanol.

[0009] Furthermore, the production of syngas usually involves the reforming of natural gas, which is itself very energy intensive, since the reaction with water is endothermic and typically takes place at high temperatures. A typical example of a cracking process is the nickel-catalyzed reaction of methane and steam at a ratio of 1:3 at 840°C. Thus, the syngas produced will have 3 mol H 2For each mole of CO composition. Alternatively, a partial oxidation reaction of methane with oxygen can be carried out to produce carbon monoxide. It can be combined with steam reforming in the same reaction zone to avoid the necessity of providing additional energy input for the reaction. However, partial oxidation (which is sometimes called autothermal reforming) will require the use of pure oxygen, i.e. such a device will require an air separation unit - a highly capital-intensive and energy-intensive device for producing pure oxygen from air. In view of the above, the entire process of manufacturing methanol from synthesis gas is complex, energy-consuming and capital-intensive.

[0010] Therefore, in view of the above, there is a need in the art to provide improved processes for producing methanol.

[0011] There is a need in the art to provide a process for producing methanol with improved efficiency. There is a particular need in the art for a methanol production process that can operate under milder production process conditions, avoiding operation at high temperatures and / or high pressures (which require large amounts of energy to maintain these temperatures and / or pressures).

[0012] There is also a need in the art to provide lower CO / CO 2 Emissions from the methanol production process.

[0013] There is a further need in the art for a methanol production process that allows the production of methanol via different strategies, in particular not starting from a synthesis gas route.

[0014] Document WO 2008 / 143940 relates to a continuous process for converting hydrocarbon feedstocks into high-value products, using molecular halogens to activate the CH bonds in the feedstocks and using electrolysis to convert the hydrogen halides formed in the process back into molecular halogens. When methanol is formed, the formation of methanol is by hydrolysis.

[0015] It is therefore an object of the present invention to provide a process for producing methanol which allows to meet at least some of the above requirements, for example by reducing the production of undesirable by-products or even preventing their production, and by avoiding the need to further dry the methanol obtained in the process, to improve the overall conversion from methane to methanol. Summary of the invention

[0016] According to the present invention, an improved process for producing methanol and hydrogen from methane is provided.

[0017] In a first aspect, the present invention provides a process for producing methanol (MeOH) and hydrogen (H 2 ) process, comprising the following steps:

[0018] a) providing a gaseous feed stream comprising methane;

[0019] b) mixing the gaseous feed stream with at least one halogen reactant (X 2) under reaction conditions effective to produce an effluent stream comprising methyl halide (MeX), hydrogen halide (HX), optionally polyhalogenated alkane, and optionally unreacted methane;

[0020] c) separating from the effluent stream obtained in step b) the following:

[0021] (i) a methyl halide (MeX) stream, optionally comprising unreacted methane; and,

[0022] (ii) hydrogen halide (HX) stream;

[0023] d) mixing the methyl halide (MeX) stream separated in step c) with a solid metal hydroxide (MOH (s) ) under reaction conditions effective to produce a metal halide (MX) and methanol (MeOH); and,

[0024] e) In the efficient production of gaseous hydrogen (H 2 ) stream and containing halogen reactant (X 2 ) under the conditions of a stream of the present invention, decomposing the hydrogen halide (HX) stream separated in step c) by electrolysis.

[0025] In some embodiments, the process further comprises the step of separating the polyhalogenated alkanes formed in step b) from the effluent stream, preferably before separating the methyl halide (MeX) stream and the hydrogen halide stream from the effluent stream.

[0026] In some embodiments, the present invention provides a process for producing methanol (MeOH) and hydrogen (H 2 ) process, comprising the following steps:

[0027] a) providing a gaseous feed stream comprising methane;

[0028] b) mixing the gaseous feed stream with at least one halogen reactant (X 2 ) under reaction conditions effective to produce an effluent stream comprising methyl halide (MeX), hydrogen halide (HX), polyhalogenated alkanes, and optionally unreacted methane;

[0029] c) separating from the effluent stream obtained in step b) the following:

[0030] (i) a methyl halide (MeX) stream, which optionally comprises unreacted methane;

[0031] (ii) a hydrogen halide (HX) stream; and

[0032] (iii) a polyhalogenated alkane stream;

[0033] d) mixing the methyl halide (MeX) stream separated in step c) with a solid metal hydroxide (MOH (s) ) under reaction conditions effective to produce a metal halide (MX) and methanol (MeOH); and,

[0034] e) In the efficient production of gaseous hydrogen (H 2 ) stream and containing halogen reactant (X 2 ) under the conditions of a stream of the present invention, decomposing the hydrogen halide (HX) stream separated in step c) by electrolysis.

[0035] In some embodiments, the polyhalogenated alkane comprises a polyhalogenated methane and optionally a polyhalogenated C 2+ Alkane.

[0036] In some embodiments, the halogen reactant is selected from bromine (Br 2 ), chlorine (Cl 2 ), fluorine (F 2 ), iodine (I 2 ) and astatine (At 2 ), and preferably bromine (Br 2 ).

[0037] In some embodiments, in step c), a hydrogen halide (HX) stream is separated from the effluent stream by contacting the effluent stream comprising the hydrogen halide with an aqueous absorbent, preferably an aqueous hydrogen halide (HX) solution, thereby forming an aqueous hydrogen halide (HX) stream.

[0038] In some embodiments, C 2+ The alkyl monohalide is formed in step b).

[0039] In some embodiments, the process comprises separating the C formed in step b) of the process from the effluent stream. 2+ and preferably the process comprises separating the C alkyl monohalide formed in step b) from the effluent stream before separating the methyl halide (MeX) stream and the hydrogen halide stream from the effluent stream. 2+ Alkyl monohalides.

[0040] In some embodiments, the gaseous feed stream comprises at least 75.0 vol% methane, and preferably at least 80.0 vol% methane, preferably at least 85.0 vol% methane, preferably at least 90.0 vol% methane, preferably at least 95.0 vol% methane, preferably at least 98.0 vol% methane, preferably at least 99.0 vol% methane, preferably at least 99.9 vol% methane, based on the total volume of the gaseous feed stream.

[0041] In some embodiments, the gaseous feed stream used in step a) of the process is substantially free of sulfur species, for example, it contains less than 1.0 mol%, or less than 0.5 mol%, or less than 0.1 mol%, or less than 0.01 mol%, or less than 0.001 mol%, or less than 0.0001 mol%, or less than 0.00001 mol% of sulfur species.

[0042] In some embodiments, the solid metal hydroxide (MOH) (s) ) is a metal hydroxide provided on a solid support, preferably wherein the support is a silica or alumina support.

[0043] In some embodiments, the process further comprises the following steps:

[0044] f) Regenerating the metal halide (MX) into a metal hydroxide (MOH) and a halogen reactant (X 2 ), and preferably by reacting the metal halide (MX) with steam and oxygen (O 2 ) or air to form a metal hydroxide (MOH) and a halogen reactant (X 2 ).

[0045] In some embodiments, the process further comprises treating the halogen reactant (X) obtained in step e) and / or step f) 2 ) returns to step b) of the process.

[0046] In some embodiments, the gaseous hydrogen (H 2 ) stream contains at least 90.0 mol %, e.g., at least 95.0 mol %, or at least 99.0 mol %, or at least 99.5 mol %, or at least 99.9 mol % hydrogen.

[0047] In some embodiments, the process further comprises the following steps:

[0048] - removing unreacted methane from the methanol produced in step d), preferably by distilling the unreacted methane, and

[0049] - Optionally, the removed unreacted methane is recycled or fed into step a) and / or step b) of the process.

[0050] In a second aspect, the present invention provides a process for producing methanol (MeOH) and hydrogen (H 2 ) system, including:

[0051] - a halogenation reactor configured to react a gaseous feed stream comprising methane with at least one halogen reactant (X2 ) into an effluent stream comprising methyl halide (MeX) and hydrogen halide (HX) and optionally unreacted methane,

[0052] - a separation system fluidly connected to the halogenation reactor and configured to receive an effluent stream from the halogenation reactor and configured to separate a hydrogen halide (HX) stream and a methyl halide (MeX) stream from the effluent stream;

[0053] a hydroxylation reactor fluidly connected to the separation system and configured to receive a methyl halide (MeX) stream from the separation system and to react the methyl halide (MeX) stream with a solid metal hydroxide (MOH (s) ) to form a metal halide (MX) and methanol (MeOH); and

[0054] an electrolysis unit comprising at least one electrolysis cell and a power source for supplying electric current to the electrolysis cell, the electrolysis cell being fluidly connected to the separation system and configured to receive a hydrogen halide (HX) stream and decompose the hydrogen halide (HX) stream into gaseous hydrogen (H 2 ) stream and containing halogen reactant (X 2 ) logistics;

[0055] - a feed stream supply system for supplying a gaseous feed stream comprising methane to the halogenation reactor;

[0056] - a halogen supply system for supplying a halogen reactant (X) to the halogenation reactor 2 );

[0057] - an effluent recovery system configured to recover an effluent stream from the halogenation reactor and feed the recovered effluent stream to the separation system;

[0058] - a methanol recovery system configured to recover a stream comprising methanol (MeOH) from the hydroxylation reactor;

[0059] - a hydrogen recovery system configured to recover gaseous hydrogen (H 2 )logistics;

[0060] - a halogen recovery system configured to recover the halogen reactant (X) from the electrolysis unit 2 );

[0061] - a hydrogen halide transfer system configured to receive a hydrogen halide (HX) stream from the separation system and to supply the received hydrogen halide (HX) stream to an electrolysis unit;

[0062] - a methyl halide transfer system configured to collect a methyl halide (MeX) stream from the separation system and to supply the collected methyl halide (MeX) stream to a hydroxylation reactor,

[0063] - Optionally, an absorbent supply line for supplying an aqueous absorbent, preferably an aqueous hydrogen halide (HX) solution, to the separation system;

[0064] - optionally, a polyhalogenated alkane removal unit configured to receive an effluent stream from said halogenation reactor and to remove polyhalogenated alkanes from said effluent stream; and,

[0065] - Optionally, C 2+ an alkyl monohalide removal unit configured to receive an effluent stream from the halogenation reactor and remove C 2+ Alkyl monohalides.

[0066] The process advantageously allows the production of a substantially pure methanol stream, e.g., substantially free of other alcohols and / or ethers, such as dimethyl ether (DME). 2 emissions and shows an improved selectivity towards the production of methanol. In addition, the present process also allows obtaining a substantially pure stream of hydrogen gas as a by-product, which can be further used in numerous downstream applications.

[0067] The present invention also provides a process for producing methanol in which no synthesis gas is involved. The production of methanol from methane is a key reaction that enables the conversion from petroleum resources to renewable resources for the production of basic chemicals. The methane used in the process can come from renewable resources, which makes the production of methanol and the basic chemicals made from the methanol more environmentally friendly.

[0068] The process is also highly efficient because it allows for the recycling (reuse) of reactants and reaction products in the same process, thereby reducing waste and / or pollution.

[0069] Furthermore, the process also allows the production of hydrogen by electrolytic decomposition of a hydrogen halide stream. Thus, at least part of the energy applied in the present process is based on electrical energy, which can be obtained from renewable sources.

[0070] The independent and dependent claims set out particular and preferred features of the invention. Features in the dependent claims may be combined with features in the independent claim or other dependent claims as appropriate.

[0071] The present invention will now be further described. In the following paragraphs, different aspects of the present invention will be defined in more detail. Unless otherwise expressly stated, each aspect so defined can be combined with any other one or more aspects. Especially, any feature that is indicated as preferred or advantageous can be combined with any other one or more features that are indicated as preferred or advantageous. BRIEF DESCRIPTION OF THE DRAWINGS

[0072] Figure 1 A process according to an embodiment of the invention and a system according to an embodiment of the invention are depicted.

[0073] Figure 2 A process according to another embodiment of the invention and a system according to an embodiment of the invention are depicted. DETAILED DESCRIPTION

[0074] In describing the present invention, the terms used should be interpreted in accordance with the following definitions, unless the context dictates otherwise.

[0075] Unless otherwise defined, all terms, including technical and scientific terms, used in disclosing the present invention have the meanings commonly understood by ordinary technicians in the field to which the present invention belongs. Through further guidance, including term definitions, the teachings of the present invention are better understood.

[0076] In the following paragraphs, different aspects of the present invention will be defined in more detail. Unless otherwise explicitly stated, each aspect so defined can be combined with any other one or more aspects. In particular, any feature indicated as being preferred or advantageous can be combined with any other one or more features indicated as being preferred or advantageous.

[0077] References throughout this specification to "one embodiment" or "an embodiment" mean that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Therefore, the phrases "in one embodiment" or "in an embodiment" appearing in various places throughout this specification do not necessarily all refer to the same embodiment, but may all refer to the same embodiment. In addition, the particular features, structures, or characteristics may be combined in one or more embodiments in any suitable manner, as will be apparent to those skilled in the art from this disclosure. In addition, although some embodiments described herein include some features included in other embodiments but not other features, the combination of features of different embodiments should be intended to be within the scope of the present invention and to form different embodiments, as will be understood by those skilled in the art.

[0078] As used herein, the terms "comprising," "comprises," and "comprised of" are synonymous with "including," "includes," or "containing," "contains," and are inclusive or open-ended and do not exclude additional, unrecited members, elements, or process steps. It will be understood that the terms "comprising," "comprises," and "comprised of" as used herein include the terms "consisting of," "consists," and "consists of."

[0079] 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. For example, "a step" means one step or more than one step.

[0080] Unless defined otherwise, all technical and scientific terms used herein have the same meanings as commonly understood by one of ordinary skill in the art.

[0081] Numerical ranges expressed by endpoints include all integers and, where appropriate, fractions contained within the range (when referring to, for example, the number of elements, 1 to 5 may include 1, 2, 3, 4, and when referring to, for example, measured values, 1.5, 2, 2.75, and 3.80 may also be included). The expression of endpoints also includes the endpoint values ​​themselves (for example, from 1.0 to 5.0 includes both 1.0 and 5.0). Any numerical range recited herein is intended to include all subranges contained therein.

[0082] As used herein, the term "about" when referring to a measurable value (e.g., a parameter, an amount, a duration, etc.) is intended to encompass variations of + / -10% or less, preferably + / -5% or less, and more preferably + / -1% or less, from the specified value, as long as these variations are suitable for implementation in the disclosed invention. It should be understood that the value referred to by the modifier "about" itself is also specifically and preferably disclosed.

[0083] The terms "wt %", "vol %" or "mol %" refer to the weight percent of a component, the volume percent of a component or the mole percent of a component, respectively, based on the total weight, total volume, or total number of moles including the component.

[0084] When describing the present invention, the terms used should be interpreted in accordance with the following definitions, unless the context dictates otherwise.

[0085] Whenever the term "substituted" is used in this invention, it is intended to indicate that one or more hydrogens on the atom indicated by the expression "substituted" are replaced with a group selected from the group indicated, provided that the normal valence of the indicated atom is not exceeded and that the substitution produces a chemically stable compound, i.e., a compound that is sufficiently robust to survive isolation to a useful degree of purity from a reaction mixture.

[0086] The term "alkyl" as a group or part of a group refers to a group of formula C n H 2n+1 wherein n is a number greater than or equal to 1. The alkyl group may be linear or branched and may be substituted as described herein. Generally, the alkyl group of the present invention contains 1 to 20 carbon atoms, preferably 1 to 18 carbon atoms, preferably 1 to 12 carbon atoms, preferably 1 to 10 carbon atoms, preferably 1 to 6 carbon atoms, more preferably 1, 2, 3, 4, 5, 6 carbon atoms. When a subscript is used after a carbon atom herein, the subscript refers to the number of carbon atoms that the named group may contain. For example, the term "C 1 -20 "Alkyl", as a group or part of a group, refers to a group of the formula -C n H 2n+1 wherein n is a number from 1 to 20. Thus, for example, C 1-20 Alkyl includes all linear or branched alkyl groups having 1 to 20 carbon atoms, and thus includes, for example, methyl, ethyl, n-propyl, isopropyl, 2-methylethyl, butyl and isomers thereof (e.g., n-butyl, isobutyl and tert-butyl); pentyl and isomers thereof, hexyl and isomers thereof, heptyl and isomers thereof, octyl and isomers thereof, nonyl and isomers thereof, decyl and isomers thereof, undecyl and isomers thereof, dodecyl and isomers thereof, tridecyl and isomers thereof, tetradecyl and isomers thereof, pentadecyl and isomers thereof, hexadecyl and isomers thereof, heptadecyl and isomers thereof, octadecyl and isomers thereof, etc. For example, C 1-10 Alkyl includes all linear or branched alkyl groups having 1 to 10 carbon atoms, and thus includes, for example, methyl, ethyl, n-propyl, isopropyl, 2-methylethyl, butyl and isomers thereof (e.g., n-butyl, isobutyl and tert-butyl); pentyl and isomers thereof, hexyl and isomers thereof, heptyl and isomers thereof, octyl and isomers thereof, nonyl and isomers thereof, decyl and isomers thereof, etc. For example, C 1-6Alkyl groups include all linear or branched alkyl groups having 1 to 6 carbon atoms, and thus include, for example, methyl, ethyl, n-propyl, isopropyl, 2-methylethyl, butyl and isomers thereof (e.g., n-butyl, isobutyl and tert-butyl); pentyl and isomers thereof, hexyl and isomers thereof, etc. In some embodiments, non-limiting examples of alkyl groups include, for example, methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, pentyl, isopentyl, 2,2-dimethyl-propyl, hexyl, 2,3-dimethyl-2-butyl, heptyl, 2,2-dimethyl-3-pentyl, 2-methyl-2-hexyl, octyl, 4-methyl-3-heptyl, nonyl, decyl, undecyl and dodecyl.

[0087] As used herein and unless otherwise indicated, the term "halo" or "halogen" as a group or part of a group refers collectively to any atom selected from fluorine (F), chlorine (Cl), bromine (Br), iodine (I) and astatine (At).

[0088] Preferred statements (features) and embodiments and uses of the invention are described below. Unless otherwise expressly stated to the contrary, each statement and embodiment of the invention so defined may be combined with any other statement and / or embodiment. In particular, any feature indicated as preferred or advantageous may be combined with any other one or more features or statements indicated as preferred or advantageous. To this end, the present invention is particularly captured (covered) by one or more of the following numbered statements and embodiments and any one or any combination of any other aspects and / or embodiments.

[0089] 1. Production of methanol (MeOH) and hydrogen (H 2 ) process, comprising the following steps:

[0090] a) providing a gaseous feed stream comprising methane;

[0091] b) mixing the gaseous feed stream with at least one halogen reactant (X 2 ) under reaction conditions effective to produce an effluent stream comprising methyl halide (MeX), hydrogen halide (HX), optionally polyhalogenated alkane, and optionally unreacted methane;

[0092] c) separating from the effluent stream obtained in step b) the following:

[0093] (i) a methyl halide (MeX) stream, optionally comprising unreacted methane; and,

[0094] (ii) hydrogen halide (HX) stream;

[0095] d) mixing the methyl halide (MeX) stream separated in step c) with a solid metal hydroxide (MOH (s)) under reaction conditions effective to produce a metal halide (MX) and methanol (MeOH);

[0096] e) In the efficient production of gaseous hydrogen (H 2 ) stream and containing halogen reactant (X 2 ) by electrolysis to decompose the hydrogen halide (HX) stream separated in step c).

[0097] 2. A process according to statement 1, wherein the process comprises a step of recovering a stream of methanol and optionally unreacted methane after step d).

[0098] 3. A process according to statement 1 or 2, wherein the process further comprises the step of separating the polyhalogenated alkanes formed in step b) from the effluent stream, preferably before separating the methyl halide (MeX) stream and the hydrogen halide stream from the effluent stream.

[0099] 4. Production of methanol (MeOH) and hydrogen (H 2 ), preferably according to any one of statements 1 to 3, comprising the following steps:

[0100] a) providing a gaseous feed stream comprising methane;

[0101] b) mixing the gaseous feed stream with at least one halogen reactant (X 2 ) under reaction conditions effective to produce an effluent stream comprising methyl halide (MeX), hydrogen halide (HX), polyhalogenated alkanes, and optionally unreacted methane;

[0102] c) separating from the effluent stream obtained in step b) the following:

[0103] (i) a methyl halide (MeX) stream, which optionally comprises unreacted methane;

[0104] (ii) a hydrogen halide (HX) stream; and

[0105] (iii) a polyhalogenated alkane stream;

[0106] d) mixing the methyl halide (MeX) stream separated in step c) with a solid metal hydroxide (MOH (s) ) under reaction conditions effective to produce a metal halide (MX) and methanol (MeOH); and,

[0107] e) In the efficient production of gaseous hydrogen (H 2 ) stream and containing halogen reactant (X 2) under the conditions of a stream of the present invention, decomposing the hydrogen halide (HX) stream separated in step c) by electrolysis.

[0108] 5. A process according to statement 4, wherein the process further comprises the step of recovering a stream of methanol and optionally unreacted methane after step d).

[0109] 6. A process according to any one of statements 1 to 5, wherein the polyhalogenated alkane comprises polyhalogenated methane and optionally polyhalogenated C 2+ Alkane.

[0110] 7. A process according to any one of statements 1 to 6, wherein the halogen reactant is selected from bromine (Br 2 ), chlorine (Cl 2 ), fluorine (F 2 ), iodine (I 2 ) and astatine (At 2 ).

[0111] 8. A process according to any one of the preceding statements, wherein the halogen reactant is bromine (Br 2 ).

[0112] 9. The process according to any of the preceding statements, wherein steps b) and d) are carried out in separate reaction steps, preferably in separate reactors or separate reaction zones.

[0113] 10. The process according to any of the preceding statements, wherein the temperature during step b) is at least 150°C, preferably at least 200°C, preferably at least 250°C, preferably at least 300°C, preferably at least 350°C, preferably at least 380°C.

[0114] 11. Process according to any of the preceding statements, wherein the temperature during step b) is at most 900°C, preferably at most 800°C, preferably at most 700°C, preferably at most 600°C, preferably at most 550°C, preferably at most 520°C.

[0115] 12. The process according to any of the preceding statements, wherein the temperature during step b) is at least 150°C to at most 900°C, preferably at least 200°C to at most 800°C, preferably at least 250°C to at most 700°C, preferably at least 300°C to at most 600°C, preferably at least 350°C to at most 550°C, preferably at least 380°C to at most 520°C.

[0116] 13. A process according to any of the preceding statements, wherein the pressure during step b) is at least 1.0 bar, preferably at least 1.5 bar, preferably at least 2.0 bar, preferably at least 2.5 bar, preferably at least 3.0 bar, preferably at least 5.0 bar, preferably at least 10.0 bar.

[0117] 14. The process according to any of the preceding statements, wherein the pressure during step b) is at most 50.0 bar, preferably at most 45.0 bar, preferably at most 40.0 bar, preferably at most 35.0 bar, preferably at most 30.0 bar, preferably at most 25.0 bar, preferably at most 20.0 bar.

[0118] 15. The process according to any of the preceding statements, wherein the pressure during step b) is at least 1.0 bar to at most 50.0 bar, preferably at least 1.5 bar to at most 45.0 bar, preferably at least 2.0 bar to at most 40.0 bar, preferably at least 2.5 bar to at most 35.0 bar, preferably at least 3.0 bar to at most 30.0 bar, preferably at least 5.0 bar to at most 25.0 bar, preferably at least 10.0 bar to at most 20.0 bar.

[0119] 16. A process according to any one of the preceding statements, wherein in step b), the gaseous feed stream is reacted with the halogen reactant (X 2 ) is contacted for at least 0.1 minutes to at most 2.0 minutes, preferably at least 0.2 minutes to at most 1.7 minutes, preferably at least 0.5 minutes to at most 1.5 minutes, preferably at least 0.7 minutes to at most 1.2 minutes.

[0120] 17. A process according to any one of the preceding statements, wherein in step c), a hydrogen halide (HX) stream is separated from an effluent stream by contacting the effluent stream comprising the hydrogen halide with an aqueous absorbent capable of absorbing the hydrogen halide (HX), preferably an aqueous hydrogen halide (HX) solution, thereby forming an aqueous hydrogen halide (HX) stream.

[0121] 18. A process according to any one of the preceding statements, wherein during step b) polyhalogenated alkanes are formed, preferably wherein the polyhalogenated alkanes formed during step b) comprise polyhalogenated methane and optionally polyhalogenated C 2+ Alkane.

[0122] 19. A process according to any of the preceding statements, wherein the polyhalogenated alkanes formed in step b) of the process comprise dihalomethanes (CH 2 X 2 ).

[0123] 20. A process according to any one of the preceding statements, wherein the process comprises the step of separating the polyhalogenated alkanes formed in step b) from the effluent stream, thereby producing a polyhalogenated alkanes stream, and preferably the process comprises separating the polyhalogenated alkanes formed in step b) from the effluent stream before separating the hydrogen halide from the effluent stream.

[0124] 21. A process according to any one of the preceding statements, wherein the polyhalogenated alkanes formed in step b) of the process are separated from the effluent stream by distillation.

[0125] 22. A process according to any one of the preceding statements, wherein the polyhalogenated alkanes formed in step b) of the process are used as a polyhalogenated methane stream and as a polyhalogenated C 2+ The alkane stream is separated from the effluent stream, preferably by distillation.

[0126] 23. A process according to any of the preceding statements, wherein C 2+ The alkyl monohalide is formed in step b).

[0127] 24. A process according to any of the preceding statements, wherein the process comprises separating the C formed in step b) of the process from the effluent stream. 2+ Alkyl monohalide step.

[0128] 25. A process according to any one of the preceding statements, wherein the process comprises separating the C formed in step b) from the effluent stream before separating the hydrogen halide from the effluent stream. 2+ Alkyl monohalides.

[0129] 26. A process according to any one of the preceding statements, wherein the process comprises separating the C2+ alkyl monohalide formed in step b) from the effluent stream after separating the polyhalogenated alkanes from the effluent stream.

[0130] 27. Production of methanol (MeOH) and hydrogen (H 2 ), preferably a process for producing methanol (MeOH) and hydrogen (H 2 ) process, comprising the following steps:

[0131] a) providing a gaseous feed stream comprising methane;

[0132] b) mixing the gaseous feed stream with at least one halogen reactant (X 2 ) in the efficient production of methyl halides (MeX), hydrogen halides (HX), polyhalogenated alkanes, C 2+reacting an alkyl monohalide and optionally an effluent stream of unreacted methane under reaction conditions;

[0133] c) separating the following substreams from the effluent stream obtained in step b):

[0134] c1) a polyhalogenated alkane stream;

[0135] c2)C 2+ an alkyl monohalide stream;

[0136] c3) a hydrogen halide (HX) stream; and

[0137] c4) a methyl halide (MeX) stream, which optionally comprises unreacted methane;

[0138] d) mixing the methyl halide (MeX) stream separated in step c) with a solid metal hydroxide (MOH (s) ) under reaction conditions effective to produce a metal halide (MX) and methanol (MeOH); and,

[0139] e) In the efficient production of gaseous hydrogen (H 2 ) stream and containing halogen reactant (X 2 ) under the conditions of a stream of the present invention, decomposing the hydrogen halide (HX) stream separated in step c) by electrolysis.

[0140] 28. A process according to statement 27, wherein the process further comprises the step of recovering a stream of methanol and optionally unreacted methane after step d).

[0141] 29. A process according to any of the preceding statements, wherein the C formed in step b) of the process 2+ The alkyl monohalide is separated from the effluent stream by distillation.

[0142] 30. The process according to any of the preceding statements, wherein the methyl halide (MeX) stream separated in step c) is a gaseous stream.

[0143] 31. A process according to any of the preceding statements, wherein the methyl halide (MeX) stream separated in step c) is substantially free of polyhalogenated alkanes.

[0144] 32. A process according to any one of the preceding statements, wherein the methyl halide (MeX) stream separated in step c) is substantially free of C 2+ Alkyl monohalides.

[0145] 33. Process according to any of the preceding statements, wherein the hydrogen halide (HX) stream obtained in step c) is dry.

[0146] 34. A process according to any of the preceding statements, wherein step c) comprises separating from the effluent stream:

[0147] (i) a methyl halide (MeX) stream, optionally comprising unreacted methane and optionally C 2+ Alkyl monohalides;

[0148] (ii) a hydrogen halide (HX) stream; and,

[0149] (iii) an optional polyhalogenated alkane stream, which may include a polyhalogenated methane stream and a polyhalogenated C 2+ Alkane Flow.

[0150] 35. A process according to any of the preceding statements, wherein the methyl halide (MeX) stream contains unreacted methane.

[0151] 36. A process according to any one of the preceding statements, wherein the methyl halide (MeX) stream comprises C 2+ Alkyl monohalides.

[0152] 37. A process according to any of the preceding statements, wherein step c) comprises separating from the effluent stream:

[0153] (i) a methyl halide (MeX) stream, which optionally comprises unreacted methane;

[0154] (ii) a hydrogen halide (HX) stream; and,

[0155] (iii) a polyhalogenated alkane stream comprising a polyhalogenated methane stream and optionally a polyhalogenated C 2+ an alkane stream; and,

[0156] (iv) Optional C 2+ Alkyl monohalide stream.

[0157] 38. A process according to any of the preceding statements, wherein the gaseous feed stream comprises at least 75.0 volume % methane, preferably at least 80.0 volume % methane, preferably at least 85.0 volume % methane, preferably at least 90.0 volume % methane, preferably at least 95.0 volume % methane, preferably at least 98.0 volume % methane, preferably at least 99.0 volume % methane, preferably at least 99.9 volume % methane, based on the total volume of the gaseous feed stream.

[0158] 39. A process according to any of the preceding statements, wherein the gaseous feed stream comprises natural gas, biogas, refinery gas, or any mixture thereof.

[0159] 40. A process according to any of the preceding statements, wherein the gaseous feed stream used in step a) of the process is substantially free of sulfur species, for example it contains less than 1.0 mol%, or less than 0.5 mol%, or less than 0.1 mol%, or less than 0.01 mol%, or less than 0.001 mol%, or less than 0.0001 mol%, or less than 0.00001 mol% of sulfur species.

[0160] 41. A process according to any one of the preceding statements, wherein the solid metal hydroxide (MOH) (s) ) is a metal hydroxide provided on a solid support, preferably wherein the support is a silica or alumina support.

[0161] 42. The process according to any one of the preceding statements, wherein the metal hydroxide is selected from the list comprising potassium hydroxide (KOH), sodium hydroxide (NaOH), barium hydroxide (Ba(OH) 2 ), cesium hydroxide (CsOH), strontium hydroxide (Sr(OH) 2 ), calcium hydroxide (Ca(OH) 2 )、Magnesium hydroxide (Mg(OH) 2 ), lithium hydroxide (LiOH), rubidium hydroxide (RbOH), and any mixture thereof.

[0162] 43. A process according to any of the preceding statements, wherein the metal hydroxide is an alkali metal hydroxide, preferably selected from potassium hydroxide (KOH), lithium hydroxide (LiOH), sodium hydroxide (NaOH), or any mixture thereof.

[0163] 44. A process according to any one of the preceding statements, wherein in step d), a methyl halide (MeX) is reacted with a solid metal hydroxide (MOH (s) ) is contacted for at least 0.1 minute to a maximum of 100.0 minutes, preferably at least 0.2 minute to a maximum of 75.0 minutes, preferably at least 0.5 minute to a maximum of 60.0 minutes, preferably at least 1.0 minute to a maximum of 45.0 minutes, preferably at least 2.0 minute to a maximum of 30.0 minutes, preferably at least 3.0 minutes to a maximum of 15.0 minutes, preferably at least 4.0 minutes to a maximum of 10.0 minutes, preferably at least 4.0 minutes to a maximum of 6.0 minutes.

[0164] 45. A process according to any of the preceding statements, wherein the temperature during step d) is at least 50°C, preferably at least 70°C, preferably at least 80°C, preferably at least 90°C, preferably at least 100°C, preferably at least 120°C.

[0165] 46. ​​A process according to any of the preceding statements, wherein the temperature during step d) is at most 500°C, preferably at most 450°C, preferably at most 400°C, preferably at most 350°C, preferably at most 300°C, preferably at most 250°C.

[0166] 47. A process according to any of the preceding statements, wherein the temperature during step d) is from at least 50°C to at most 500°C, preferably from at least 70°C to at most 450°C, preferably from at least 80°C to at most 400°C, preferably from at least 90°C to at most 350°C, preferably from at least 100°C to at most 300°C, preferably from at least 120°C to at most 250°C.

[0167] 48. A process according to any of the preceding statements, wherein the pressure during step d) is at least 1.0 bar, preferably at least 1.2 bar, preferably at least 1.5 bar, preferably at least 1.7 bar, preferably at least 2.0 bar, preferably at least 5.0 bar, preferably at least 10.0 bar.

[0168] 49. A process according to any of the preceding statements, wherein the pressure during step d) is at most 40.0 bar, preferably at most 35.0 bar, preferably at most 30.0 bar, preferably at most 25.0 bar, preferably at most 20.0 bar, preferably at most 15.0 bar, preferably at most 10.0 bar.

[0169] 50. A process according to any of the preceding statements, wherein the pressure during step d) is at least 1.0 bar to a maximum of 40.0 bar, preferably at least 1.2 bar to a maximum of 35.0 bar, preferably at least 1.5 bar to a maximum of 30.0 bar, preferably at least 1.7 bar to a maximum of 25.0 bar, preferably at least 2.0 bar to a maximum of 20.0 bar, preferably at least 5.0 bar to a maximum of 20.0 bar, preferably at least 10.0 bar to a maximum of 15.0 bar.

[0170] 51. A process according to any one of the preceding statements, wherein the polyhalogenated alkane is converted to its corresponding alcohol, preferably by hydrogenating the polyhalogenated alkane to a monohalide and subsequently reacting the monohalide with a solid metal hydroxide (MOH (s) ) under reaction conditions effective to produce the corresponding alcohol.

[0171] 52. A process according to any of the preceding statements, wherein C 2+ The alkyl monohalide is converted to its corresponding alcohol, preferably by reacting the C 2+ Alkyl monohalides and solid metal hydroxides (MOH (s) ) under reaction conditions effective to produce the corresponding alcohol.

[0172] 53. A process according to any one of the preceding statements, wherein the process further comprises the following steps:

[0173] f) Regenerating the metal halide (MX) into a metal hydroxide (MOH) and a halogen reactant (X 2 ).

[0174] 54. The process according to any of the preceding statements, wherein the metal halide (MX) is regenerated in step f) by reacting the metal halide (MX) with steam and oxygen (O 2 ) or air to form a metal hydroxide (MOH) and a halogen reactant (X 2 ).

[0175] 55. A process according to any of the preceding statements, wherein the temperature during step f) is at least 150°C, preferably at least 200°C, preferably at least 250°C, preferably at least 300°C, preferably at least 350°C, preferably at least 400°C.

[0176] 56. A process according to any of the preceding statements, wherein the temperature during step f) is at most 1600°C, preferably at most 1400°C, preferably at most 1200°C, preferably at most 1000°C, preferably at most 800°C, preferably at most 600°C.

[0177] 57. A process according to any of the preceding statements, wherein the temperature during step f) is at least 150°C to a maximum of 1600°C, preferably at least 200°C to a maximum of 1400°C, preferably at least 250°C to a maximum of 1200°C, preferably at least 300°C to a maximum of 1000°C, preferably at least 350°C to a maximum of 800°C, preferably at least 400°C to a maximum of 600°C.

[0178] 58. A process according to any of the preceding statements, wherein the pressure during step f) is at least 0.5 bar, preferably at least 0.8 bar, preferably at least 0.9 bar, preferably at least 1.0 bar, preferably at least 1.1 bar, preferably at least 5.0 bar, preferably at least 10.0 bar.

[0179] 59. A process according to any of the preceding statements, wherein the pressure during step f) is at most 50.0 bar, preferably at most 45.0 bar, preferably at most 40.0 bar, preferably at most 35.0 bar, preferably at most 30.0 bar, preferably at most 25.0 bar, preferably at most 20.0 bar, preferably at most 15.0 bar.

[0180] 60. A process according to any of the preceding statements, wherein the pressure during step f) is from at least 0.5 bar to at most 50.0 bar, preferably from at least 0.8 bar to at most 45.0 bar, preferably from at least 0.9 bar to at most 40.0 bar, preferably from at least 1.0 bar to at most 35.0 bar, preferably from at least 1.1 bar to at most 30.0 bar, preferably from at least 5.0 bar to at most 25.0 bar, preferably from at least 10.0 bar to at most 20.0 bar, preferably from at least 10.0 bar to at most 15.0 bar.

[0181] 61. A process according to any one of the preceding statements, further comprising reacting the halogen reactant (X) obtained in step e) and / or step f) 2 ) returns to step b) of the process.

[0182] 62. A process according to any one of the preceding statements, wherein the halogen reactant (X) obtained in step e) and / or step f) is purified before being fed into step b). 2 ), and preferably by a halogen reactant (X 2 ) for purification by condensation.

[0183] 63. A process according to any one of the preceding statements, wherein the halogen reactant (X) obtained in step e) and / or step f) is dried before being fed into step b). 2 ), preferably dried over molecular sieves.

[0184] 64. A process according to any of the preceding statements, wherein step e) of the process comprises supplying an aqueous solution of hydrogen halide (HX) to an electrolytic cell comprising a positive electrode and a negative electrode, and electrolytically decomposing the hydrogen halide by maintaining a potential of about 0.5 to 2.5 V between the electrodes.

[0185] 65. A process according to any one of the preceding statements, wherein step e) of the process comprises supplying an aqueous solution of hydrogen halide (HX) to an electrolytic cell comprising a positive electrode and a negative electrode and reacting the electrolyte by maintaining a current between the electrodes of about 100 to 800 mA / cm 2 The hydrogen halide is electrolytically decomposed by a current density of .

[0186] 66. A process according to any of the preceding statements, wherein the electrolytic cell is a polymer electrolyte membrane cell (PEM) containing at least a proton conducting membrane.

[0187] 67. A process according to any of the preceding statements, wherein the hydrogen halide is decomposed in step e) at a temperature of 20 to 95°C.

[0188] 68. The process according to any of the preceding statements, wherein the hydrogen halide is decomposed in step e) at a pressure of 1 to 50 bar.

[0189] 69. A process according to any one of the preceding statements, wherein the gaseous hydrogen (H 2 ) stream contains at least 90.0 mol %, e.g., at least 95.0 mol %, or at least 99.0 mol %, or at least 99.5 mol %, or at least 99.9 mol % hydrogen.

[0190] 70. A process for producing methanol (MeOH) and hydrogen (H2) from methane according to any one of the preceding statements. 2 ) process, comprising the following steps:

[0191] a) providing a gaseous feed stream comprising methane,

[0192] b) mixing the gaseous feed stream with bromide (Br 2 ) under reaction conditions effective to produce an effluent stream comprising methyl bromide (MeBr) and hydrogen bromide (HBr), and wherein the effluent stream optionally comprises unreacted methane and optionally poly-brominated alkanes;

[0193] c) separating from the effluent stream obtained in b) the following:

[0194] (i) a methyl bromide (MeBr) stream, optionally comprising unreacted methane, and

[0195] (ii) a hydrogen bromide (HBr) stream;

[0196] (iii) optionally, a polybrominated alkane stream;

[0197] d) mixing the methyl bromide (MeBr) stream separated in step c) with a solid metal hydroxide (MOH (s) ) under reaction conditions effective to produce a metal bromide (MBr) and methanol (MeOH); and,

[0198] e) In the efficient production of gaseous hydrogen (H 2 ) stream and containing bromine (Br 2 ), decomposing the hydrogen bromide (HBr) stream separated in step c) by electrolysis, and

[0199] f) optionally, regenerating the metal bromide (MBr) into a metal hydroxide (MOH) and bromine (Br 2 ), preferably by reacting a metal bromide (MBr) with steam and oxygen (O 2 ) or air to form metal hydroxide (MOH) and bromine (Br 2 ),and

[0200] g) optionally, the bromine (Br) obtained in step e) and / or step f) 2 ) returns to step b) of the process.

[0201] 71. A process according to any of the preceding statements, wherein the process further comprises the step of removing unreacted methane from the effluent stream, preferably distilling the unreacted methane.

[0202] 72. A process according to any one of the preceding statements, wherein the process further comprises the step of removing unreacted methane from the methyl halide (MeX) stream, preferably distilling the unreacted methane.

[0203] 73. A process according to any one of the preceding statements, wherein the process further comprises the step of removing unreacted methane from the methanol produced in step d), preferably distilling the unreacted methane.

[0204] 74. A process according to any of the preceding statements, wherein removed unreacted methane is recycled or fed to step a) and / or step b) of the process.

[0205] 75. A process according to any of the preceding statements, wherein the process is a continuous process.

[0206] 76. Production of methanol (MeOH) and hydrogen (H 2 ) system, including:

[0207] - a halogenation reactor (1) configured to react a gaseous feed stream comprising methane with at least one halogen reactant (X 2 ) into an effluent stream comprising methyl halide (MeX) and hydrogen halide (HX) and optionally unreacted methane,

[0208] - a separation system (2) fluidly connected to the halogenation reactor (1) and configured to receive an effluent stream from the halogenation reactor (1) and configured to separate a hydrogen halide (HX) stream and a methyl halide (MeX) stream from the effluent stream;

[0209] a hydroxylation reactor (3) fluidically connected to the separation system (2) and configured to receive a methyl halide (MeX) stream from the separation system (2) and to react the methyl halide (MeX) stream with a solid metal hydroxide (MOH (s) ) to form a metal halide (MX) and methanol (MeOH); and

[0210] an electrolysis unit (4) comprising at least one electrolysis cell and a power source for supplying electric current to the electrolysis cell, the electrolysis cell being fluidically connected to the separation system (2) and configured to receive a hydrogen halide (HX) stream and to decompose the hydrogen halide (HX) stream into gaseous hydrogen (H 2 ) stream and containing halogen reactant (X 2 ) logistics;

[0211] - a feed stream supply system (5) for supplying a gaseous feed stream comprising methane to the halogenation reactor (1);

[0212] - a halogen supply system (6) for supplying a halogen reactant (X) to the halogenation reactor (1); 2 );

[0213] - an effluent collection system (10) configured to collect an effluent stream from the halogenation reactor (1) and feed the collected effluent stream to the separation system (2);

[0214] - a methanol recovery system (7) configured to recover a stream comprising methanol (MeOH) from the hydroxylation reactor (3);

[0215] - a hydrogen collection system (8) configured to collect gaseous hydrogen (H 2 )logistics;

[0216] - a halogen collecting system (9) configured to collect the halogen reactant (X) from the electrolysis unit (4); 2 );

[0217] - a hydrogen halide transfer system (12) configured to collect a hydrogen halide (HX) stream from the separation system (2) and supply the collected hydrogen halide (HX) stream to the electrolysis unit (4);

[0218] - a methyl halide transfer system (11) configured to collect a methyl halide (MeX) stream from the separation system (2) and supply the collected methyl halide (MeX) stream to the hydroxylation reactor (3),

[0219] - Optionally, an absorbent supply line (12) for supplying an aqueous absorbent, preferably an aqueous hydrogen halide (HX) solution, to the separation system (2);

[0220] - optionally, a polyhalogenated alkane removal unit configured to receive the effluent stream from the halogenation reactor (1) and to remove polyhalogenated alkanes from the effluent stream; and,

[0221] - Optionally, C 2+an alkyl monohalide removal unit configured to receive an effluent stream from the halogenation reactor (1) and remove C 2+ Alkyl monohalides.

[0222] In a first aspect, the present invention provides a process for producing methanol (MeOH) and hydrogen (H 2 ). The process particularly comprises the following steps:

[0223] a) providing a gaseous feed stream comprising methane;

[0224] b) mixing the gaseous feed stream with at least one halogen reactant (X 2 ) under reaction conditions effective to produce an effluent stream comprising methyl halide (MeX) and hydrogen halide (HX), and wherein the effluent stream optionally comprises unreacted methane;

[0225] c) separating from the effluent stream obtained in step b) the following:

[0226] (i) a methyl halide (MeX) stream, optionally comprising unreacted methane; and,

[0227] (ii) hydrogen halide (HX) stream;

[0228] d) mixing the methyl halide (MeX) stream separated in step c) with a solid metal hydroxide (MOH (s) ) under reaction conditions effective to produce a metal halide (MX) and methanol (MeOH); and,

[0229] e) In the efficient production of gaseous hydrogen (H 2 ) stream and containing halogen reactant (X 2 ) under the conditions of a stream of the present invention, decomposing the hydrogen halide (HX) stream separated in step c) by electrolysis.

[0230] More specifically, the production of methanol (MeOH) and hydrogen (H 2 ) process comprises the following steps:

[0231] a) providing a gaseous feed stream comprising methane;

[0232] b) mixing the gaseous feed stream with at least one halogen reactant (X 2 ) under reaction conditions effective to produce an effluent stream comprising methyl halide (MeX), hydrogen halide (HX), optionally polyhalogenated alkane, and optionally unreacted methane;

[0233] c) separating from the effluent stream obtained in step b) the following:

[0234] (i) a methyl halide (MeX) stream, optionally comprising unreacted methane; and,

[0235] (ii) hydrogen halide (HX) stream;

[0236] (iii) optionally, a polyhalogenated alkane stream;

[0237] d) mixing the methyl halide (MeX) stream separated in step c) with a solid metal hydroxide (MOH (s) ) under reaction conditions effective to produce a metal halide (MX) and methanol (MeOH); and,

[0238] e) In the efficient production of gaseous hydrogen (H 2 ) stream and containing halogen reactant (X 2 ), decomposing the hydrogen halide (HX) stream separated in step c) by electrolysis,

[0239] f) Regenerating the metal halide (MX) into a metal hydroxide (MOH) and a halogen reactant (X 2 ), preferably by reacting the metal halide (MX) with steam and oxygen (O 2 ) or air to form a metal hydroxide (MOH) and a halogen reactant (X 2 );and

[0240] g) optionally, the halogen reactant (X) obtained in step e) and / or step f) 2 ) returns to step b) of the process.

[0241] In some embodiments, the process specifically comprises the following steps:

[0242] a) providing a gaseous feed stream comprising methane;

[0243] b) mixing the gaseous feed stream with at least one halogen reactant (X 2 ) under reaction conditions effective to produce an effluent stream comprising methyl halide (MeX) and hydrogen halide (HX), and wherein the effluent stream optionally comprises unreacted methane;

[0244] c) separating from the effluent stream obtained in step b) the following:

[0245] (i) a methyl halide (MeX) stream, which optionally comprises unreacted methane;

[0246] (ii) a hydrogen halide (HX) stream; and, or

[0247] (iii1) a polyhalogenated alkane stream; or

[0248] (iii2) a polyhalogenated methane stream and optionally a polyhalogenated C 2+ Alkane streams;

[0249] d) mixing the methyl halide (MeX) stream separated in step c) with a solid metal hydroxide (MOH (s) ) under reaction conditions effective to produce a metal halide (MX) and methanol (MeOH);

[0250] e) In the efficient production of gaseous hydrogen (H 2 ) stream and containing halogen reactant (X 2 ), decomposing the hydrogen halide (HX) stream separated in step c) by electrolysis;

[0251] f) Regenerating the metal halide (MX) into a metal hydroxide (MOH) and a halogen reactant (X 2 ), preferably by reacting a metal halide (MX) with steam and oxygen (O 2 ) or air to form a metal hydroxide (MOH) and a halogen reactant (X 2 );and

[0252] g) optionally, the halogen reactant (X) obtained in step e) and / or step f) 2 ) returns to step b) of the process.

[0253] According to the invention, it is preferred that steps b) and d) are carried out in separate reaction steps, preferably in separate reactors or separate reaction zones. The process of the invention is preferably a continuous process.

[0254] In some preferred embodiments of the present invention, the process comprises a step of recovering a stream of methanol and optionally unreacted methane after step d).

[0255] The present invention provides a process for producing a stream of methanol and hydrogen starting from a gaseous feed stream comprising or consisting essentially of methane (e.g. biogas or natural gas). In other words, the present invention provides a process for producing methanol from a gaseous stream comprising methane (not synthesis gas).

[0256] The process comprises reacting a gaseous feed stream with at least one halogen reactant to form a methyl halide and a hydrogen halide, and then reacting the produced methyl halide to form a metal halide and methanol in the presence of a solid metal hydroxide. The process is further characterized in that it comprises the following steps: separating the methyl halide produced by reacting the gaseous feed stream with the halogen reactant from other halogen-containing compounds (and in particular from the hydrogen halide produced in this step), and then subjecting the produced methyl halide to a hydroxylation reaction in the presence of the solid metal hydroxide. Such a separation step upstream of the hydroxylation step advantageously and unexpectedly allows the methyl halide stream to be efficiently converted into a methanol stream with minimal or no production of undesirable byproducts, such as, for example, dimethyl ether (DME).

[0257] In addition, the present process also provides the following step: wherein the separated hydrogen halide can be treated electrolytically to decompose into separate streams of hydrogen and halogen reactants, thereby producing a valuable by-product, namely hydrogen. In addition, the recovered halogen reactants can be advantageously reused in the present process.

[0258] Thus, the present process provides an efficient process for converting methane to methanol, wherein hydrogen is produced as an industrially relevant by-product.

[0259] The first step of the process comprises providing a gaseous feed stream comprising methane.

[0260] The terms "gaseous feed stream" and "reactant gas" are used herein as synonyms and refer to a gaseous stream comprising methane.

[0261] In some embodiments of the process according to the invention, the gaseous feed stream used may also contain C 2+ Alkane.

[0262] The term "alkane" refers to an organic compound that is either a non-cyclic saturated hydrocarbon or a cyclic saturated hydrocarbon. As used herein, an alkane may be straight-chain, branched, or cyclic (but not aromatic). Preferably, the alkane is straight-chain or branched. In a preferred embodiment, the alkane is a non-cyclic saturated hydrocarbon and satisfies the following formula C i H (2i+2) , where i is an integer. Examples are methane, ethane, propane, butane, pentane and hexane.

[0263] As used herein, the term "C 2+ "Alkanes" is intended to mean alkanes having greater than two carbon atoms. In some embodiments, C 2+ Alkanes are C 2-6 Alkanes, that is, alkanes containing two to six carbon atoms, so for example C 2 , C 3 , C 4 , C5 , C 6 Alkanes, and any mixtures thereof. When a subscript is used after a carbon atom herein, the subscript refers to the number of carbon atoms the named group may contain. 2+ Examples of alkanes are ethane, propane, butane, pentane, hexane, and mixtures of two or more of these.

[0264] For example, in some embodiments, the gaseous feed stream employed may comprise a mixture of methane and ethane, or a mixture of methane and propane, or a mixture of methane, ethane, and propane.

[0265] Preferably, the gaseous feed stream comprising methane used in the present process comprises at least 75.0% by volume of methane, preferably at least 80.0% by volume of methane, preferably at least 85.0% by volume of methane, preferably at least 90.0% by volume of methane, preferably at least 95.0% by volume of methane, preferably at least 98.0% by volume of methane, preferably at least 99.0% by volume of methane, preferably at least 99.9% by volume of methane, based on the total volume of the gaseous feed stream.

[0266] Optionally, the gaseous feed stream applied in the process according to the invention may also contain hydrogen. Preferably, the molar ratio of this optional hydrogen to methane in the gaseous feed stream may be in the range of about 1:4 to 0:1.

[0267] Optionally, the gaseous feed stream used in the process according to the present invention may also contain a small amount of other components selected from oxygen, nitrogen or carbon dioxide. Preferably, such other components can be less than 2.0 mol%, such as less than 1.5 mol%, or less than 1.0 mol%, or less than 0.5 mol% of the amount present, based on the total gaseous feed stream. In some embodiments, the composition of the gaseous feed stream is comparable to that of natural gas or biogas, or a mixture thereof.

[0268] In some embodiments, the gaseous feed stream used in step a) of the process comprises natural gas, biogas, refinery gas (i.e., a gaseous fraction from a crude oil refinery), or any mixture thereof. Preferably, the gaseous feed stream comprises natural gas and / or biogas.

[0269] In some embodiments of the process according to the invention, the gaseous feed stream gas used in step a) of the process is natural gas. The term "natural gas" refers to a multi-component gas obtained from a crude oil well (associated gas) or from an underground gas-bearing formation (non-associated gas). The composition and pressure of natural gas can vary significantly. A typical natural gas stream contains methane as a significant component. Natural gas may also contain ethane, higher molecular weight hydrocarbons (e.g., C2+ alkanes), acid gases (e.g., carbon dioxide, hydrogen sulfide, carbonyl sulfide, carbon disulfide, and mercaptans), and small amounts of contaminants such as water, nitrogen, iron sulfide, wax, and crude oil. As used herein, "natural gas" may also include gas obtained from the regasification of liquefied natural gas, which has been purified to remove contaminants (e.g., water, acid gases) and most of the higher molecular weight hydrocarbons (e.g., C2+ alkanes). 12+ Conventional methods may be used to remove impurities and / or adjust the relative amounts of hydrocarbon compounds present in the gaseous feed stream.

[0270] In some embodiments of the process according to the invention, the gaseous feed stream gas used in step a) of the process is biogas or biomethane produced from biogas. The term "biogas" refers to a multi-component gas consisting mainly of methane and carbon dioxide, produced by anaerobic digestion or by methanogenesis from feedstocks such as, but not limited to, agricultural waste, manure, municipal waste, plant material, sewage, green waste or food waste. Biogas can be purified to remove carbon dioxide, oxygen, sulfur and / or silicon-containing compounds to produce biomethane, which can be used as the gaseous feed stream in the present process.

[0271] In some embodiments, the natural gas may be of fossil origin. In some embodiments, the natural gas may be of renewable origin. Natural gas of renewable origin includes, for example, gas produced from existing waste streams and various renewable and sustainable biomass sources (including but not limited to animal waste, crop residues and food waste, organic waste from cattle farms and farms), and gas produced from the biological decomposition of organic waste that occurs naturally in facilities such as wastewater treatment plants and landfills. In some embodiments, the natural gas may comprise a combination of natural gas from fossil sources and natural gas from renewable sources.

[0272] Preferably, the gaseous feed stream used in step a) of the process is substantially free of sulfur species, for example, it contains less than 1.0 mol%, or less than 0.5 mol%, or less than 0.1 mol%, or less than 0.01 mol%, or less than 0.001 mol%, or less than 0.0001 mol%, or less than 0.00001 mol% of sulfur species. In an example, the gaseous feed stream is free of sulfur species. For example, sulfur species may refer to, for example, H 2 S, COS, CS2 If desired, desulfurization can be achieved by adsorption and / or absorption.

[0273] In some other embodiments of the process according to the invention, the gaseous feed stream consists of methane.

[0274] Step b) of the process of the invention comprises reacting a gaseous feed stream as defined herein with at least one halogen reactant (X 2 ) under reaction conditions effective to produce an effluent stream comprising methyl halide (MeX) and hydrogen halide (HX). The effluent stream may optionally contain unreacted methane.

[0275] The halogen reactant used in this step of the process may be selected from bromine (Br 2 ), chlorine (Cl 2 ), fluorine (F 2 ) and iodine (I 2 ), and preferably bromine. In particular, the recovery of bromine in processes e) and f) requires less energy, reactants and / or equipment.

[0276] Thus, in a preferred embodiment, the present invention provides a process for producing methanol (MeOH) and hydrogen (H 2 ) process, comprising the following steps:

[0277] a) providing a gaseous feed stream comprising methane;

[0278] b) mixing the gaseous feed stream with bromine (Br 2 ) under reaction conditions effective to produce an effluent stream comprising methyl bromide (MeBr), hydrogen bromide (HBr), and wherein the effluent stream optionally comprises unreacted methane;

[0279] c) separating hydrogen bromide (HBr) from the effluent stream to recover a methyl bromide (MeBr) stream;

[0280] d) mixing the separated methyl bromide (MeBr) stream separated in step c) with a solid metal hydroxide (MOH (s) ) under reaction conditions effective to produce metal bromide (MBr) and methanol (MeOH);

[0281] e) In the efficient production of gaseous hydrogen (H 2 ) stream and containing bromine (Br 2 ), decomposing the hydrogen bromide (HBr) separated in step c) by electrolysis;

[0282] f) optionally, regenerating the metal bromide (MBr) into a metal hydroxide (MOH) and bromine (Br2 );and,

[0283] g) optionally, the bromine (Br) obtained in step e) and / or step f) 2 ) returns to step b) of the process.

[0284] Preferably, the halogen reactant, such as bromine, is introduced directly into the reaction zone. The halogen reactant can be introduced into the reaction zone in a liquid state. The halogen reactant can be introduced into the reaction zone in pure form, or dissolved in an aqueous hydrogen halide solution.

[0285] According to the present process, step b) of the process is preferably carried out at a temperature during step b) of at least 150° C., preferably at least 200° C., preferably at least 250° C., preferably at least 300° C., preferably at least 350° C., preferably at least 380° C. According to the present process, step b) of the process is preferably carried out at a temperature during step b) of at most 900° C., preferably at most 800° C., preferably at most 700° C., preferably at most 600° C., preferably at most 550° C., preferably at most 520° C.

[0286] For example, in the present process, preferred temperature conditions for the reaction between the feed stream comprising methane and the halogen reactant are included between 150° C. and 900° C., preferably included between 200° C. and 800° C., preferably included between 250° C. and 700° C., preferably included between 300° C. and 600° C., preferably included between 350° C. and 550° C., preferably included between 380° C. and 520° C. In some embodiments, the exothermic nature of the reaction is sufficient to maintain the temperature during the reaction.

[0287] According to the present process, step b) of the process is carried out at a reaction pressure of at least 1.0 bar, preferably at least 1.5 bar, preferably at least 2.0 bar, preferably at least 2.5 bar, preferably at least 3.0 bar, preferably at least 5.0 bar, preferably at least 10.0 bar. According to the present process, step b) of the process is carried out at a reaction pressure of at most 50.0 bar, preferably at most 45.0 bar, preferably at most 40.0 bar, preferably at most 35.0 bar, preferably at most 30.0 bar, preferably at most 25.0 bar, preferably at most 20.0 bar.

[0288] For example, preferred pressure conditions for the reaction between a feed stream comprising methane and a halogen reactant in the present process include between 1.0 bar and 50.0 bar, preferably between 1.5 bar and 45.0 bar, preferably between 2.0 bar and 40.0 bar, preferably between 2.5 bar and 35.0 bar, preferably between 3.0 bar and 30.0 bar, preferably between 5.0 bar and 25.0 bar, and preferably between 10.0 bar and 20.0 bar.

[0289] In some embodiments of the present process, the feed stream comprising methane and the halogen reactant are applied in a methane / halogen molar ratio comprised between 2 / 1 and 7 / 1, preferably between 3 / 1 and 6 / 1, preferably between 4 / 1 and 5 / 1.

[0290] The time required for the gaseous feed stream to react with the halogen will vary depending on the specific feed material used, the halogen used and the reaction temperature. In an example, the gaseous feed stream is reacted with the halogen reactant (X) in step b). 2 ) at a temperature between 380°C and 520°C, at a pressure between 10 bar and 20 bar, and for at least 0.1 minute and at most 2.0 minutes.

[0291] The effluent stream obtained from the reaction step b) mainly comprises methyl halides and hydrogen halides. The effluent stream may also contain a certain amount of unreacted methane. At the same time, depending on the composition of the initial gaseous feed stream used in the process, the effluent stream may contain a certain amount of C 2+ Alkyl monohalides and / or a certain amount of polyhalogenated alkanes, such as polyhalogenated methane and / or polyhalogenated C 2+ Alkanes, which have been formed during reaction step b).

[0292] In the next step, the process of the present invention comprises separating the following from the effluent stream obtained in step b): a methyl halide (MeX) stream and a hydrogen halide (HX) stream. The methyl halide stream is then further reacted with a solid metal hydroxide (in step d) of the process), while the hydrogen halide stream is electrolyzed (in step e) of the process).

[0293] In a preferred embodiment, in step c) of the process, the hydrogen halide (HX) stream is separated from the effluent stream by contacting the effluent stream comprising the hydrogen halide with an aqueous absorbent capable of absorbing the hydrogen halide (HX). For example, the hydrogen halide (HX) stream can be separated from the effluent stream in a separation system (e.g., in a quench column), preferably by contacting the gaseous effluent stream with a suitable aqueous absorbent, preferably in countercurrent contact.

[0294] Preferably, the aqueous absorbent used in step c) of the process is an aqueous hydrogen halide (HX) solution.

[0295] In some preferred embodiments of the present invention, the aqueous absorbent used in the process is an aqueous hydrogen halide (HX) solution, wherein the halogen anion used in the solution, such as a bromide anion, is the same halogen as the halogen reactant used in step b) of the process, such as bromine. Therefore, in some preferred embodiments, the halogen reactant used in step a) is bromide (Br 2), and the hydrogen halide solution used in step c) is a hydrogen bromide (HBr) solution.

[0296] Preferably, the hydrogen halide solution as applied during separation step c) contains a weight fraction of hydrogen halide (HX) of at least 10.0 wt.-% to at most 40.0 wt.-%, for example at least 15.0 wt.-% to at most 35.0 wt.-%, or at least 20.0 wt.-% to at most 30.0 wt.-%, or at least 25.0 wt.-% to at most 30.0 wt.-%, wherein the wt.-% are expressed based on the total hydrogen halide solution.

[0297] In some embodiments of the process of the present invention, the effluent stream may comprise additional components in addition to methyl halide, hydrogen halide and optionally unreacted methane, depending on the composition of the initial gaseous feed stream used in the process.

[0298] In some embodiments of the process of the present invention, polyhalogenated alkanes are formed in step b) and are present in the effluent stream obtained after step b).

[0299] The term "polyhalogenated alkane" as used herein is an alkane in which more than one hydrogen atom is replaced by a halogen atom (X), wherein X is preferably selected from Br, Cl, F, I and At, more preferably X is Br. As used herein, "polyhalogenated alkane" preferably refers to polyhalogenated alkanes such as polyhalogenated C 1 -C 6 Alkanes, preferably polyhalogenated C 1 -C 4 Alkanes, preferably polyhalogenated C 1 -C 3 Alkanes. When a subscript is used herein after a carbon atom, the subscript refers to the number of carbon atoms the named group may contain.

[0300] In some embodiments, the term "polyhalogenated alkane" refers to a compound having the following formula (I):

[0301]

[0302] in:

[0303] -n is an integer, and n≥1, preferably 1≤n≥6; preferably 1≤n≥4; preferably 1≤n≥3;

[0304] - m is an integer, and m≥2; preferably 2≤m≥4, preferably 2≤m≥3; and,

[0305] -X is selected from Br, Cl, F, I and At, preferably X is Br.

[0306] In some embodiments, the polyhalogenated alkane comprises a polyhalogenated C 1 Alkane.

[0307] In some embodiments, the polyhalogenated alkane comprises a polyhalogenated C 2+ Alkane.

[0308] In some embodiments, the polyhalogenated alkane comprises a polyhalogenated C 1 Alkanes and polyhalogenated C 2+ Alkane.

[0309] The term "polyhalogenated C 1 "Alkanes" and "polyhalomethanes" are used interchangeably herein and are intended to mean C 1 Alkanes, wherein X is preferably selected from Br, Cl, F, I and At, more preferably wherein X is Br.

[0310] In some embodiments, the term "polyhalogenated C 1 "Alkanes" and "polyhalomethanes" refer to compounds having the following formula (II):

[0311]

[0312] in:

[0313] - p is an integer, and p≥2; preferably 2≤p≥4, preferably 2≤p≥3; and,

[0314] -X is selected from Br, Cl, F, I and At, and preferably X is Br.

[0315] In some preferred embodiments, the "polyhalogenated methane" is selected from CH 2 X 2 , CHX 2 and CX 4 , and any mixture thereof, wherein X is as defined above. For example, the polyhalogenated methane formed in step b) of the process includes dihalomethane (CH 2 X 2 ). Preferred examples of polyhalogenated methanes include, but are not limited to, CH 2 Br 2 , CHBr 3 and CBr 4 .

[0316] As used herein, the term "polyhalogenated C 2+ "Alkanes" refer to the following C 2+ Alkanes: wherein more than one hydrogen atom is replaced by a halogen atom (X), wherein X is preferably selected from Br, Cl, F, I and At, more preferably X is Br. Preferably, the polyhalogenated C 2+ Alkanes preferably refer to polyhalogenated C 2+ Alkanes such as polyhalogenated C 2 -C6 Alkanes, preferably polyhalogenated C 2 -C 4 Alkanes, preferably polyhalogenated C 2 -C 3 Alkane.

[0317] In some embodiments, the polyhalogenated C 2+ "Alkanes" refer to compounds having the following formula (III):

[0318]

[0319] in:

[0320] -q is an integer and q≥2, preferably 2≤q≥6; preferably 2≤q≥4; preferably 2≤q≥3;

[0321] - r is an integer and r≥2; preferably 2≤r≥4, preferably 2≤r≥3; and,

[0322] -X is selected from Br, Cl, F, I and At, preferably X is Br.

[0323] For example, the polyhalogenated C 2+ Alkanes may include polyhalogenated C 2 Alkanes (e.g. ethylene dibromide) and / or polyhalogenated C 3 Alkanes (eg dibromopropane).

[0324] In some embodiments of the process of the present invention, C 2+ Alkyl monohalides are also formed in step b) and are present in the effluent stream obtained after step b).

[0325] The term "C 2+ Alkyl monohalide" and "monohalogenated C 2+ "Alkanes" are used interchangeably herein and refer to the following C 2+ Alkanes: wherein a single hydrogen atom is replaced by a halogen atom (X), wherein X is preferably selected from Br, Cl, F, I and At, more preferably wherein X is Br. Preferably, the monohalogenated C 2+ Alkanes preferably refer to monohalogenated C 2+ For example, monohalogenated C 2 -C 6 Alkanes, preferably monohalogenated C 2 -C 4 Alkanes, preferably monohalogenated C 2 -C 3 Alkane.

[0326] In other words, the term “C 2+ Alkyl monohalide" and "monohalogenated C 2+"Alkanes" refer to compounds having the following formula (IV):

[0327]

[0328] in:

[0329] -s is an integer, and s≥2; preferably 2≤s≥6; preferably 2≤s≥4; preferably 2≤s≥3, and,

[0330] -X is selected from Br, Cl, F, I and At, preferably X is Br.

[0331] For example, the C formed in step b) of the process 2+ The alkyl monohalides may include C 2 Alkyl monohalide (e.g. ethyl bromide) and / or C 3 Alkyl monohalides (eg n-propyl bromide).

[0332] In view of this, the present process may include separating the polyhalogenated alkanes and / or C 2+ Thus, in some embodiments, step c) in the process of the present invention comprises separating the following from the effluent stream obtained in step b):

[0333] - a methyl halide (MeX) stream; which optionally contains unreacted methane and / or optionally C 2+ Alkyl monohalides;

[0334] - a hydrogen halide (HX) stream; and

[0335] - Polyhalogenated alkane streams.

[0336] In some embodiments, C 2+ The alkyl monohalide is separated from the effluent stream in a separate stream, namely in C 2+ Alkyl monohalide stream.

[0337] In some embodiments, it is preferred to separate the polyhalogenated alkane stream from the effluent stream by distillation, as follows:

[0338] - a stream which can be further separated, preferably by distillation, into a polyhalogenated methane stream and a polyhalogenated C 2+ an alkane stream; or,

[0339] -Polyhalogenated methane streams and polyhalogenated C 2+ Alkane Flow.

[0340] In some embodiments, step c) comprises a single separation step of the effluent stream, i.e., the effluent stream is separated in one step. In some embodiments, step c) comprises two separation steps, i.e., a hydrogen halide (HX) separation step and a polyhalogenated alkane separation step. In some embodiments, step c) comprises three separation steps, i.e., a hydrogen halide (HX) separation step, a polyhalogenated alkane separation step, and a C 2+ Alkyl monohalide separation step.

[0341] In one example, step c) in the process of the present invention comprises separating from the effluent stream obtained in step b) the following:

[0342] - a methyl halide (MeX) stream; which optionally comprises unreacted methane and / or optionally comprises C 2+ Alkyl monohalides;

[0343] - a hydrogen halide (HX) stream; and,

[0344] - Polyhalogenated alkane streams.

[0345] In a further example, step c) in the process of the present invention comprises separating from the effluent stream obtained in step b) the following:

[0346] - a methyl halide (MeX) stream; which optionally comprises unreacted methane and / or optionally comprises C 2+ Alkyl monohalides;

[0347] - a hydrogen halide (HX) stream; and,

[0348] - a polyhalogenated methane stream; and,

[0349] -Polyhalogenated C 2+ Alkane Flow.

[0350] In a further example, step c) in the process of the present invention comprises separating from the effluent stream obtained in step b) the following:

[0351] - a methyl halide (MeX) stream; which optionally comprises unreacted methane;

[0352] - a hydrogen halide (HX) stream; and,

[0353] -C 2+ Alkyl monohalide stream.

[0354] In a further example, step c) in the process of the present invention comprises separating from the effluent stream obtained in step b) the following:

[0355] - a methyl halide (MeX) stream; which optionally comprises unreacted methane;

[0356] - Hydrogen halide (HX) streams;

[0357] - a polyhalogenated alkane stream; and,

[0358] -C 2+ Alkyl monohalide stream.

[0359] In a further example, step c) in the process of the present invention comprises separating from the effluent stream obtained in step b) the following:

[0360] - a methyl halide (MeX) stream; which optionally comprises unreacted methane;

[0361] - Hydrogen halide (HX) streams;

[0362] - Polyhalogenated methane streams;

[0363] -Polyhalogenated C 2+ an alkane stream; and,

[0364] -C 2+ Alkyl monohalide stream.

[0365] Separation of polyhalogenated alkanes from the effluent stream has the following advantages: it allows recovery of a purified methyl halide (MeX) stream containing less or no other polyhalogenated alkanes, such as polyhalogenated methane and / or polyhalogenated C 2+ Alkanes, and thus such a purified methyl halide (MeX) stream can be advantageously converted into a stream of methanol without producing significant amounts of non-alcohol products other than alkanes. In this way, methanol can be produced: non-alcohol products other than alkanes are less than 10.000 ppm, preferably less than 7.000 ppm, preferably less than 5.000 ppm, preferably less than 3.000 ppm, preferably less than 2.000 ppm, preferably less than 1.000 ppm.

[0366] In particular, the process for producing methanol (MeOH) and hydrogen (H 2 ) preferably comprises the following steps:

[0367] a) providing a system comprising methane and optionally C 2+ a gaseous feed stream of an alkane;

[0368] b) mixing the gaseous feed stream with at least one halogen reactant (X 2 ) under reaction conditions effective to produce an effluent stream comprising methyl halide (MeX), hydrogen halide (HX), and wherein the effluent stream optionally comprises unreacted methane; C 2+ Alkyl monohalides and / or polyhalogenated alkanes, such as polyhalogenated methane and / or polyhalogenated C 2+Alkanes;

[0369] c) separating from the effluent stream obtained in step b) the following:

[0370] (i) a methyl halide (MeX) stream, which optionally comprises unreacted methane;

[0371] (ii) hydrogen halide (HX) stream;

[0372] (iii) an optional polyhalogenated alkane stream, which may include a polyhalogenated methane stream and / or a polyhalogenated C 2+ an alkane stream; and,

[0373] (iv) Optional C 2+ Alkyl monohalide stream.

[0374] d) mixing the methyl halide (MeX) stream separated in step c) with a solid metal hydroxide (MOH (s) ) under reaction conditions effective to produce a metal halide (MX) and methanol (MeOH);

[0375] e) In the efficient production of gaseous hydrogen (H 2 ) stream and containing halogen reactant (X 2 ), decomposing the hydrogen halide (HX) stream separated in step c) by electrolysis;

[0376] f) optionally, regenerating the metal halide (MX) into a metal hydroxide (MOH) and a halogen reactant (X 2 );

[0377] g) optionally, the halogen reactant (X) obtained in step e) and / or step f) 2 ) returning to step b) of the process; and

[0378] h) optionally, the polyhalogenated alkane stream and / or C2 + The alkyl monohalide stream is converted to its corresponding alcohol.

[0379] Preferably, the polyhalogenated alkanes formed in step b) of the process are separated from the effluent stream by distillation. For example, the polyhalogenated alkane stream or the polyhalogenated methane stream and the polyhalogenated C 2+ The alkane stream is separated from the effluent stream. Preferably, distillation may be a preferred separation technique due to the large difference in molecular weight and therefore boiling point between polyhalogenated alkanes and monohalogenated compounds. Preferably, the polyhalogenated alkanes are separated from the effluent stream, and then the monohalogenated compounds (i.e., methyl halides, hydrogen halides, and C 2+ alkyl monohalide) is separated from the effluent stream.

[0380] In some preferred embodiments of the present invention, the process comprises the step of separating the polyhalogenated alkanes formed in step b) from the effluent stream to produce a polyhalogenated alkanes stream, whereby the polyhalogenated alkanes formed in step b) are separated from the effluent stream before separating the hydrogen halide from the effluent stream.

[0381] Preferably, the C formed in step b) of the process is distilled 2+ The alkyl monohalide is separated from the effluent stream. For example, the C 2+ An alkyl monohalide stream is separated from the effluent.

[0382] In some preferred embodiments of the present invention, the process comprises the following steps: 2+ Alkyl monohalide is separated from the effluent stream to produce C 2+ alkyl monohalide stream, thereby separating the hydrogen halide from the effluent stream Before , the C formed in step b) 2+ The alkyl monohalide is separated from the effluent stream, preferably by distillation.

[0383] In some embodiments, the process comprises mixing a polyhalogenated methane stream with a polyhalogenated C 2+ The alkane stream is separated in a separate step and / or in a separate separation column. Alternatively, the process may include separating the polyhalogenated methane stream and the polyhalogenated C 2+ The alkane stream is separated in a single step and / or in a single separation column.

[0384] In some embodiments, the process includes separating the polyhalogenated alkane stream and the methyl halide stream in separate steps and / or in separate separation towers. Alternatively, the process may include separating the polyhalogenated alkane stream and the methyl halide stream in a single step and / or in a single separation tower.

[0385] The methyl halide (MeX) stream separated in step c) is preferably a gaseous stream.

[0386] In step c), hydrogen halide (HX) and optionally a polyhalogenated alkane stream and / or C 2+After the alkyl monohalide stream is separated, the present process allows to collect a stream mainly comprising methyl halide (MeX). Preferably, the separated methyl halide stream comprises at least 75.0 mol%, such as at least 80.0 mol%, or at least 85.0 mol%, or at least 90.0 mol% of methyl halide, based on the total amount of the stream. However, it should be noted that the separated methyl halide stream may still contain a certain amount of unreacted methane.

[0387] Preferably, the methyl halide (MeX) stream separated in step c) is substantially free of hydrogen halide. In this context, the term "substantially free of hydrogen halide" is intended to mean that the amount of hydrogen halide in the stream is less than 10.00 mol%, such as less than 8.00 mol%, or less than 5.00 mol%, or less than 3.00 mol%, or less than 1.00 mol%, or less than 0.10 mol%, preferably less than 0.05 mol%, preferably less than 0.01 mol%, based on the total amount of the stream.

[0388] According to the present invention, the methyl halide (MeX) stream separated in step c) is also preferably "substantially free" of polyhalogenated alkanes. "Substantially free of polyhalogenated alkanes" in this context means that the methyl halide (MeX) stream obtained in step c) contains less than 1.0 mol %, such as less than 0.1 mol %, preferably less than 0.5 mol % of polyhalogenated alkanes, as defined herein.

[0389] According to the present invention, the methyl halide (MeX) stream separated in step c) is also preferably "substantially free" of polyhalogenated methanes. "Substantially free of polyhalogenated methanes" in this context means that the methyl halide (MeX) stream obtained in step c) contains less than 1.0 mol %, such as less than 0.1 mol %, preferably less than 0.5 mol % of polyhalogenated methanes, as defined herein.

[0390] According to the present invention, the methyl halide (MeX) stream separated in step c) is also preferably "substantially free" of polyhalogenated C 2+ Preferably, "substantially free of polyhalogenated C 2+ By "alkanes" is meant that the methyl halide (MeX) stream obtained in step c) contains less than 1.0 mol %, such as less than 0.1 mol %, preferably less than 0.5 mol % of polyhalogenated C 2+ Alkanes are as defined herein.

[0391] According to the present invention, the methyl halide (MeX) stream separated in step c) is also preferably "essentially free" of C 2+ Preferably, "substantially free of C 2+"Alkyl monohalide" means that the methyl halide (MeX) stream obtained in step c) contains less than 1.0 mol %, such as less than 0.1 mol %, preferably less than 0.5 mol % of C 2+ Alkyl monohalide as defined herein.

[0392] In the next step, the methyl halide (MeX) stream separated in step c) of the process is mixed with a solid metal hydroxide (MOH (s) ) under reaction conditions effective to produce a metal halide (MX) and methanol (MeOH).

[0393] Examples of suitable metal hydroxides for use in the present process include, but are not limited to, metal hydroxides selected from the list comprising or consisting of: potassium hydroxide (KOH), sodium hydroxide (NaOH), barium hydroxide (Ba(OH) 2 ), cesium hydroxide (CsOH), strontium hydroxide (Sr(OH) 2 ), calcium hydroxide (Ca(OH) 2 ), lithium hydroxide (LiOH), rubidium hydroxide (RbOH), magnesium hydroxide (Mg(OH) 2 ), and any mixture thereof.

[0394] Preferred examples of solid metal hydroxides may be alkali metal hydroxides, such as potassium hydroxide (KOH), lithium hydroxide (LiOH), sodium hydroxide (NaOH), or any mixture thereof. A particularly preferred example is potassium hydroxide (KOH).

[0395] The term "solid" as used herein refers to a metal hydroxide provided on a solid support, such as a silica or alumina support, more preferably a silica support. Preferably, the solid support is impregnated with the metal hydroxide. Preferably, the solid support is impregnated with a solution of the metal hydroxide and the impregnated solid support is then dried.

[0396] Step d) of the process of the present invention is preferably carried out at a temperature of at least 50°C, preferably at least 70°C, preferably at least 80°C, preferably at least 90°C, preferably at least 100°C, preferably at least 150°C. Step d) of the process of the present invention is preferably carried out at a temperature of at most 500°C, preferably at most 450°C, preferably at most 400°C, preferably at most 350°C, preferably at most 300°C, preferably at most 250°C. For example, preferred temperature conditions for reaction step d) include between 50°C and 500°C, preferably between 70°C and 450°C, preferably between 80°C and 400°C, preferably between 90°C and 350°C, preferably between 100°C and 300°C, preferably between 120°C and 250°C. In some embodiments, the temperature in step d) can be achieved by heat integration, for example using heat harvested during the exothermic reaction in step b).

[0397] Step d) of the process of the present invention is preferably carried out at a reaction pressure of at least 1.0 bar, preferably at least 1.2 bar, preferably at least 1.5 bar, preferably at least 1.7 bar, preferably at least 2.0 bar, preferably at least 5.0 bar, preferably at least 10.0 bar. Step d) of the process of the present invention is preferably carried out at a reaction pressure of at most 40.0 bar, preferably at most 35.0 bar, preferably at most 30.0 bar, preferably at most 25.0 bar, preferably at most 20.0 bar, preferably at most 15.0 bar, preferably at most 10.0 bar. For example, preferred pressure conditions for reaction step d) include between 1.0 bar and 40.0 bar, preferably between 1.2 bar and 35.0 bar, preferably between 1.5 bar and 30.0 bar, preferably between 1.7 bar and 25.0 bar, preferably between 2.0 bar and 20.0 bar, preferably between 5.0 bar and 20.0 bar, preferably between 10.0 bar and 15.0 bar.

[0398] Preferably, the process of the invention comprises reacting a methyl halide (MeX) with a solid metal hydroxide (MOH (s) ) is reacted for at least 0.1 minute to at most 100.0 minutes, preferably at least 0.2 minute to at most 75.0 minutes, preferably at least 0.5 minute to at most 60.0 minutes, preferably at least 1.0 minute to at most 45.0 minutes, preferably at least 2.0 minute to at most 30.0 minutes, preferably at least 3.0 minutes to at most 15.0 minutes, preferably at least 4.0 minutes to at most 10.0 minutes, preferably at least 4.0 minutes to at most 6.0 minutes.

[0399] In an example, the methyl halide is contacted with the solid metal hydroxide in step d) at a temperature between 120 and 250°C, at a pressure between 10 and 15 bar, and for at least 4 minutes and at most 6.0 minutes.

[0400] The reaction products obtained from reaction step d) comprise mainly methanol (methanol stream) and metal halide (MX). In the reaction output there are also optionally residual amounts of unreacted methane.

[0401] In some preferred embodiments, the present process includes a step of collecting a stream comprising methanol and optionally unreacted methane after step d). After step d), a stream comprising methanol may be collected. Preferably, the methanol stream collected comprises, based on the total amount of the stream, at least 75.0 mol%, such as at least 80.0 mol%, or at least 85.0 mol%, or at least 95.0 mol% methanol. However, it will be noted that the methanol stream collected may still comprise a certain amount of unreacted methane.

[0402] By separating the hydrogen halide from the effluent stream obtained after step b) of the process of the invention, the present process allows a "purified" methyl halide stream to be subjected to a hydroxylation reaction in the presence of a solid metal hydroxide in step d). Thus, the separation step applied in step c) allows the reaction of the hydrogen halide on the solid metal hydroxide in step d) to be avoided. In this way, the present process avoids the conversion of hydrogen halide (HX) into metal halide (MX) and water during step d) of the process. Instead, the hydrogen halide (HX) present in the effluent stream after reaction step b) is further decomposed (in step e)) into:

[0403] - a substantially pure hydrogen gas stream which makes economic sense over water; and

[0404] - a halogen reactant which can advantageously be reused in step b) of the process.

[0405] By separating the hydrogen halide from the effluent stream in step c), the production of "wet methanol" can also be prevented in step d); thereby avoiding the need for further drying of the methanol obtained in the process. Moreover, in the absence of hydrogen halide in the methyl halide stream supplied in step d), the solid metal hydroxide applied in step d) of the process is still most suitable for converting methyl halide into methanol and does not undergo side reactions with such hydrogen halide. In addition, by preventing the formation of metal halide (MX) due to interaction with hydrogen halide, the need / frequency of regenerating the metal halide formed in step d) into solid metal hydroxide (which is necessary for converting methyl halide into methanol) is greatly reduced.

[0406] The hydrogen halide stream obtained in step c) of the process is subjected to decomposition to release hydrogen and halogen for recovery. The halogen reactant may be recycled to steps a) and / or b) of the process, for example added to the feed stream supplied in step a) and / or supplied separately during reaction step b).

[0407] The preferred way of decomposing the hydrogen halide is electrolysis. Therefore, this step of the process of the present invention is preferably carried out in an electrolytic cell, preferably in a polymer electrolyte membrane cell (PEM) containing at least a proton conducting membrane. Polymer electrolyte membrane (PEM) electrolysis is well known in the art and comprises a cell equipped with a solid polymer electrolyte (SPE) which is responsible for the conduction of protons, the separation of gaseous products and the electrical insulation of the electrodes.

[0408] In some embodiments of the invention, step e) of the process comprises the steps of supplying an aqueous solution of hydrogen halide to an electrolytic cell (such as defined herein) comprising a positive electrode and a negative electrode, and electrolytically decomposing the hydrogen halide by maintaining a potential of about 0.5 to 2.5 V between the electrodes.

[0409] In some embodiments of the invention, step e) of the process comprises the steps of supplying an aqueous solution of hydrogen halide to an electrolytic cell (as defined herein) comprising a positive electrode and a negative electrode, and electrolytically decomposing the hydrogen halide by maintaining a current density between the electrodes of about 100 to 800 mA / cm2.

[0410] The potential required to decompose the hydrogen halide solution decreases with the increase of the temperature of the aqueous solution. It is particularly preferred to carry out the electrolytic decomposition at a temperature of about 20 to 95° C., and preferably about 40 to 80° C. The pressure in the electrolytic decomposition zone is kept high enough to keep the aqueous hydrogen halide in the liquid phase. Generally, the pressure will be in the range of about 0.1 to 5 MPa (1-50 bar).

[0411] The gaseous hydrogen (H) produced in step e) of the process 2 ) stream contains at least 90.0 mol%, such as at least 95.0 mol%, or at least 99.0 mol%, or at least 99.5 mol%, or at least 99.9 mol% hydrogen. The hydrogen obtained by the process according to the invention can be used for downstream applications. For example, it can be used for ammonia synthesis, for hydrogenation purposes, for chemical synthesis, or for energy generation by combustion in a gas turbine (with or without additional hydrocarbon fuels), etc. The produced hydrogen can also be used as a chemical feedstock to reduce dependence on oil and natural gas.

[0412] The halogen reactant (X) produced in step e) of the process 2 ) can be reused in step b) of the process, for example after suitable pretreatment such as purification and / or drying.

[0413] In some preferred embodiments, the halogen reactant (X 2 ) is purified, for example by condensation, before being returned to step b).

[0414] In some preferred embodiments, the halogen reactant (X 2 ) is dried before returning to step b). Preferably, the halogen reactant (X 2 ) is dried over molecular sieves. Preferably, in the halogen reactant (X 2 ) before returning to step b), the halogen reactant (X 2 ) is at most 2000 ppm, preferably at most 1500 ppm, preferably at most 1000 ppm, preferably at most 750 ppm, preferably at most 500 ppm, wherein ppm is expressed as the weight of water relative to the total weight of the halogen reactants.

[0415] In some embodiments of the present invention, the process of the present invention further comprises the following step f): regenerating the metal halide (MX) formed in step d) into a metal hydroxide (MOH) and a halogen reactant (X 2 ).

[0416] The terms "regeneration" and "conversion" are used as synonyms in this context. The process preferably comprises reacting the metal halide (MX) obtained in step d) of the process with a reactant (X) capable of forming MOH and a halogen. 2 ) to collect the metal hydroxide and halogen reactants.

[0417] The "regeneration agent" used in step f) of the process may include steam, oxygen and / or air. For example, the process preferably comprises recovering the metal hydroxide and the halogen reactant by contacting the metal halide (MX) obtained in step d) of the process with steam and oxygen or with air to form MOH and the halogen reactant (X 2 The particular ratio of steam to air or oxygen may depend on the particle size, the loading of the metal hydroxide on the solid support and the selected regeneration temperature. An excess of air is preferably used.

[0418] According to the present invention, it is preferred that step f) of the process is carried out at a temperature of at least 150° C., preferably at least 200° C., preferably at least 250° C., preferably at least 300° C., preferably at least 350° C., preferably at least 400° C. It is preferred that step f) of the process is carried out at a temperature of at most 1600° C., preferably at most 1400° C., preferably at most 1200° C., preferably at most 1000° C., preferably at most 800° C., preferably at most 600° C. For example, the temperature during step f) of the process is from at least 150° C. to at most 1600° C., preferably from at least 200° C. to at most 1400° C., preferably from at least 250° C. to at most 1200° C., preferably from at least 300° C. to at most 1000° C., preferably from at least 350° C. to at most 800° C., preferably from at least 400° C. to at most 600° C. Preferably, the temperature during step f) may be maintained by the exothermic reaction in step f) and optionally by providing steam.

[0419] According to the present invention, it is preferred that step f) of the process is carried out at a pressure of at least 0.5 bar, preferably at least 0.8 bar, preferably at least 0.9 bar, preferably at least 1.0 bar, preferably at least 1.1 bar, preferably at least 5.0 bar, preferably at least 10.0 bar during step f). Preferably, step f) of the process is carried out at a pressure of at most 50.0 bar, preferably at most 45.0 bar, preferably at most 40.0 bar, preferably at most 35.0 bar, preferably at most 30.0 bar, preferably at most 25.0 bar, preferably at most 20.0 bar during step f). For example, the reaction pressure during step f) is from at least 0.5 bar to at most 50.0 bar, preferably from at least 0.8 bar to at most 45.0 bar, preferably from at least 0.9 bar to at most 40.0 bar, preferably from at least 1.0 bar to at most 35.0 bar, preferably from at least 1.1 bar to at most 30.0 bar, preferably from at least 5.0 bar to at most 25.0 bar, preferably from at least 10.0 bar to at most 20.0 bar, preferably from at least 10.0 bar to at most 15.0 bar.

[0420] In an example, the temperature during step b) is at least 300°C to a maximum of 600°C, and the pressure during step b) is at least 5.0 bar to a maximum of 30.0 bar. In a further example, the temperature during step b) is included between 380°C and 520°C, and the pressure during step b) is included between 10.0 bar and 20.0 bar. In an example, the temperature during step d) is at least 100°C to a maximum of 300°C, and the pressure during step d) is at least 2.0 bar to a maximum of 20.0 bar. In a further example, the temperature during step d) is included between 120°C and 250°C, and the pressure during step d) is included between 10.0 bar and 15.0 bar. In an example, the temperature during step f) is at least 300°C to a maximum of 1000°C, and the pressure during step f) is at least 1.1 bar to a maximum of 30.0 bar. In a further example, the temperature during step f) is comprised between 400°C and 600°C, and the pressure during step f) is comprised between 10.0 bar and 15.0 bar.

[0421] In some cases, the metal halide formed in step d) can be separated from the metal hydroxide to carry out step f). During step d), it can also occur that the amount of solid metal hydroxide is depleted and the amount of metal halide on the solid support increases, thereby forming a mixture of metal hydroxide and metal halide on the solid support. In such a case, the mixture of metal hydroxide and metal halide formed on the solid support during step d) can be subjected to a regeneration step f).

[0422] The regeneration of the metal halide (MX) formed in step d) to metal hydroxide cannot be carried out simultaneously with the conversion of methyl halide to methanol during this step. Therefore, in some embodiments, a portion of the solid support (e.g., a mixture comprising metal halides and metal hydroxides) can be separated or isolated from the reactor or reaction zone to be regenerated in step f), while another portion is used to perform step d). For example, multiple beds of solid metal hydroxide can be used so that one bed can be used for the formation of methanol in step d), while the other beds are regenerated in step g). In such an embodiment, the reactor bed can alternatively be subjected to regeneration according to step f). The metal hydroxide obtained by the regeneration step can be reused in the process as the solid metal hydroxide in step d).

[0423] Regeneration results in the formation of a gaseous effluent comprising a halogen reactant, steam, oxygen and optionally nitrogen. Preferably, the halogen reactant (X) is condensed from the gaseous effluent. 2 ) and the halogen reactant (X 2) is isolated from the gaseous effluent. The halogen reactant obtained can also be reused in step b) of the process, for example after a suitable pretreatment such as purification and / or drying.

[0424] In some preferred embodiments, the halogen reactant (X 2 ) is purified, for example by condensation, before being returned to step b).

[0425] In some preferred embodiments, the halogen reactant (X 2 ) is dried before returning to step b). Preferably, the halogen reactant (X 2 ) is dried over molecular sieves. Preferably, in the halogen reactant (X 2 ) before returning to step b), the halogen reactant (X 2 ) is at most 2000 ppm, preferably at most 1500 ppm, preferably at most 1000 ppm, preferably at most 750 ppm, preferably at most 500 ppm, wherein ppm is expressed as the weight of water relative to the total weight of the halogen reactants.

[0426] In some embodiments of the process according to the invention, the polyhalogenated alkane is converted to its corresponding alcohol, preferably by hydrogenating the polyhalogenated alkane to a monohalide and subsequently reacting the monohalide with a solid metal hydroxide (MOH (s) ) under reaction conditions effective to produce the corresponding alcohol.

[0427] In some embodiments of the process according to the invention, polyhalogenated methane is formed during step b) and may be separated during step c), as described above. In some embodiments, the process of the invention therefore further comprises the step of converting the polyhalogenated methane (e.g. separated in step c)) into methanol, preferably by hydrogenating the polyhalogenated methane to form methyl halide, followed by reacting the methyl halide with a solid metal hydroxide (MOH (s) ) under reaction conditions effective to produce the corresponding methanol, preferably under reaction conditions as defined herein.

[0428] In some embodiments of the process according to the invention, the polyhalogenated C 2+ Alkanes may also be formed during step b) and may be separated during step c), as described above. In some embodiments, the process of the invention therefore further comprises the step of: 2+ Alkanes are converted to their corresponding alcohols, preferably by hydrogenation to the corresponding C 2+ monohalide, then making the C 2+ Monohalide compounds and solid metal hydroxides (MOH(s) ) in the effective production of the corresponding C 2+ contacting under reaction conditions of an alcohol.

[0429] In some embodiments of the invention, unreacted methane may remain present in the effluent stream obtained in step b) of the process. In some embodiments of the invention, unreacted methane may remain present in the methyl halide stream obtained in step c) of the process. In some embodiments of the invention, unreacted methane may remain present in the stream of methanol obtained in step d) of the process. The remaining unreacted methane may be removed from the corresponding stream, for example, by distillation. In some preferred embodiments of the invention, such removed unreacted methane may be recycled or fed to step a) and / or step b) of the process.

[0430] The present invention provides a system for producing methanol and hydrogen from methane, comprising:

[0431] - a halogenation reactor (1) configured to react a gaseous feed stream comprising methane with at least one halogen reactant (X 2 ) into an effluent stream comprising methyl halide (MeX) and hydrogen halide (HX) and optionally unreacted methane,

[0432] - a separation system (2) fluidly connected to the halogenation reactor (1) and configured to receive an effluent stream from the halogenation reactor (1) and configured to separate a hydrogen halide (HX) stream and a methyl halide (MeX) stream from the effluent stream;

[0433] - a hydroxylation reactor (3) fluidly connected to the separation system (2) and configured to receive a methyl halide stream from the separation system (2) and react the methyl halide stream with a solid metal hydroxide to form a metal halide (MX) and methanol (MeOH); and

[0434] - an electrolysis unit (4) comprising at least one electrolysis cell and a power source for supplying electric current to the electrolysis cell, the electrolysis cell being fluidically connected to the separation system (2) and configured to receive a hydrogen halide stream and to decompose the hydrogen halide stream into a gaseous hydrogen stream and a stream comprising a halogen reactant.

[0435] As used herein, the term "fluidically connected" or "fluid connection" is used as a synonym in this article and is intended to refer to the connection between two components (or units or devices, etc.) of the system given herein, so that a fluid can flow from one component (e.g., unit, device, reactor, etc.) to another through the connection. Preferably, two fluidly connected components are connected so that the outlet of the first component is connected to the inlet of the second component through a pipe, a conduit or a series of pipes or conduits. Other components (e.g., separators, dryers, condensers, etc.) can be fluidly connected between two fluidly connected components.

[0436] The term "supply device" or "supply system" is used herein as a synonym and refers to a suitable system allowing the supply of streams, or reaction products, or reactants, and includes, for example, pipes, conduits, supply lines, inlet lines, connecting lines, etc.

[0437] The term "recovery device" or "recovery system" is used herein as a synonym and refers to a suitable system that allows for the recovery of a stream or reaction products or reactants and includes, for example, pipes, recovery lines, outlet lines, connecting lines, etc. A "recovery device" or "recovery system" may include a separation device.

[0438] The term "transfer device" or "transfer system" is also used as a synonym in this article and refers to a suitable system that allows the transfer (transport) of logistics or reaction products or reactants (for example, from one unit or reactor to another unit or reactor), and includes, for example, pipes, conduits, collection pipelines, outlet pipelines, connecting pipelines, etc.

[0439] The halogenation reactor (1) used in the system of the present invention may be any type of reactor suitable for allowing a gaseous feed stream comprising methane to react with a halogen reactant under appropriate conditions to produce an effluent stream comprising methyl halide (MeX) and hydrogen halide (HX).

[0440] In some preferred embodiments, the separation system (2) used in the system of the present invention comprises a quench tower, or consists of a quench tower. In a preferred embodiment of the present invention, the separation system (preferably a quench tower) is equipped with an inlet system configured to supply the absorbent defined herein to the system or tower.

[0441] The hydroxylation reactor (3) used in the system of the present invention may be any type of reactor suitable for containing the solid metal hydroxide defined herein and allowing a (gaseous) methyl halide stream to react with the solid metal hydroxide under appropriate conditions to produce metal halide (MX) and methanol (MeOH).

[0442] In an example, the hydroxylation reactor (3) is a swing-bed reactor. As used herein, the term "swing-bed reactor" is a reactor comprising at least two beds for containing solid metal hydroxides, the beds being arranged so that one bed can be regenerated while the other bed can be used to convert metal halides into methanol.

[0443] In another example, the hydroxylation reactor (3) comprises at least one, preferably at least two fluidized beds. In particular, when there are at least two fluidized beds, one bed can be stopped and regenerated while the other bed is still used to convert methyl halide into methanol.

[0444] The electrolysis unit (4) for use in the present invention comprises at least one electrolysis cell and a power supply for supplying electric current to the electrolysis cell. A particularly suitable electrolysis cell is a polymer electrolyte membrane cell (PEM) comprising at least one proton conducting membrane. One of the greatest advantages of PEM electrolysis is its ability to operate at high current densities. This can lead to reduced operating costs. Polymer electrolytes allow PEM electrolysis cells to be operated through very thin membranes (~100-200 μm) while still allowing high pressures, resulting in low ohmic losses, which are mainly caused by proton conduction across the membrane (0.1 S / cm) and compressed hydrogen output. Due to its solid structure, polymer electrolyte membranes advantageously provide very high product gas purity.

[0445] The system according to the present invention may also include

[0446] - a feed stream supply system (5) for supplying a gaseous feed stream comprising methane to the halogenation reactor (1); and

[0447] - A halogen supply system (6) for supplying halogen reactant to the halogenation reactor (1).

[0448] Such a system for supplying reactants to the halogenation reactor may include an inlet line (conduit), which is optionally equipped with a control device to control the flow rate of the reactant stream to the reaction zone. In a preferred embodiment of the present invention, a separate device (separate inlet line or conduit) may be provided for each reactant in the process (i.e., gaseous feed stream and halogen reactant alone).

[0449] The system according to the present invention may further comprise an effluent recovery system (10), such as a conduit or a pipeline, configured to recover the effluent stream from the halogenation reactor (1) and adapted to feed the recovered effluent stream to a downstream separation system (2).

[0450] The system according to the present invention may also include

[0451] - a hydrogen halide transfer system (12) configured to collect a hydrogen halide stream from the separation system (2) and supply the collected hydrogen halide stream to the electrolysis unit (4); and

[0452] - a methyl halide transfer system (11) configured to recover the methyl halide stream from the separation system (2) and supply the recovered methyl halide stream to the hydroxylation reactor (3).

[0453] Such a system for supplying reactants to or withdrawing reactants from the separation system may comprise an inlet line (conduit, pipe, pipeline), optionally provided with control means, for example for controlling the flow rate of the reactants to the reaction zone.

[0454] The system according to the present invention may further comprise an absorbent supply line (17) for supplying an aqueous absorbent, preferably an aqueous hydrogen halide (HX) solution, to the separation system (2). The absorbent supply line is, for example, an inlet line for supplying an absorbent, such as an aqueous solution of hydrogen halide, to the separation zone.

[0455] The system according to the invention may also include a system for separately collecting a gaseous hydrogen stream and a stream containing a halogen reactant from the electrolysis unit. Such a system particularly includes:

[0456] - a hydrogen recovery system (8) configured to recover a gaseous hydrogen stream from the electrolysis unit (4);

[0457] - a halogen recovery system (9) configured to recover the halogen reactant from the electrolysis unit (4);

[0458] Such a system for supplying reactants to or withdrawing reactants from the separation system may comprise an inlet line (conduit, pipe, pipeline), which is optionally provided with control means, for example; for controlling the flow rate of the reactants to the reaction zone.

[0459] Optionally, the system of the present invention may be provided with means (20) (e.g., a transfer line or conduit) for returning the stream of halogen reactant collected from the electrolysis unit or at least a portion thereof to the halogenation reactor. This allows the halogen reactant to be reused in the system.

[0460] In some preferred embodiments, the means (20) for returning the stream of halogen reactant withdrawn from the electrolysis unit (4) or a portion thereof to the halogenation reactor (1) comprises one or more connecting lines (connecting pipes).

[0461] In some embodiments, the one or more connecting lines for returning the stream of halogen reactant to the halogenation reactor may be provided with one or more driers (e.g., molecular sieves) suitable for drying the stream of halogen reactant before feeding it to the halogenation reactor.

[0462] In some embodiments, the one or more connecting pipelines for returning the stream of halogen reactant to the halogenation reactor may be provided with one or more purification devices (such as, for example, one or more condensers), which are suitable for purifying the stream of halogen reactant before feeding it to the halogenation reactor.

[0463] Furthermore, the system of the present invention comprises a methanol recovery system (7) configured to recover a stream comprising methanol from the hydroxylation reactor (3).

[0464] In some embodiments of the invention, polyhalogenated alkanes may be formed in step b) of the process. Such polyhalogenated alkanes may, for example, comprise methyl dihalide (CH 2 X 2 ). Therefore, the system according to the present invention may, in some embodiments, include a polyhalogenated alkane removal unit configured to receive the effluent stream from the halogenation reactor (1) and remove polyhalogenated alkanes from the effluent stream, thereby producing a polyhalogenated alkane stream and a methyl halide stream.

[0465] Preferably, such a polyhalogenated alkane removal unit is arranged downstream of the halogenation reactor (1) and upstream of the separation system (2), and is connected, preferably fluidly connected, to the halogenation reactor (1) and the separation system (2), for example via connecting lines (15, 16).

[0466] The polyhalogenated alkane removal unit may, for example, comprise:

[0467] a separation system (13), such as a separation (e.g. distillation) column, configured to receive the effluent stream from the halogenation reactor (1) and to separate a polyhalogenated alkane stream from the effluent stream,

[0468] a supply system (15), such as a supply line or pipeline, configured to supply the effluent stream from the halogenation reactor (1) to the separation column, and

[0469] - a polyhalogenated alkane recovery system (14), such as an outlet line or pipeline, configured to recover the polyhalogenated alkane stream from the separation system (13).

[0470] The polyhalogenated alkane removal unit preferably also includes a device (such as a transfer line or pipeline) for collecting a product stream (e.g., a product stream comprising methyl halides and hydrogen halide) from which the polyhalogenated alkanes defined herein have been removed. Preferably, such a device is configured to transfer the collected product stream to a downstream separation system to further separate the product stream, e.g., to separate into a separate methyl halide stream and a separate hydrogen halide stream.

[0471] In some embodiments, the polyhalogenated alkane removal unit is capable of separating polyhalogenated alkanes from the effluent stream into a polyhalogenated methane stream and a polyhalogenated C 2+ In some embodiments, the polyhalogenated alkane removal unit includes a polyhalogenated methane outlet and a polyhalogenated C 2+ Alkane export.

[0472] In some embodiments of the invention, C as defined herein 2+ Alkyl monohalide may be formed in step b) of the process. Therefore, in some embodiments, the system according to the present invention may also include C 2+ an alkyl monohalide removal unit configured to receive an effluent stream from the halogenation reactor (1) and remove C 2+ Alkyl monohalides.

[0473] In some embodiments, such C 2+ The alkyl monohalide removal unit is disposed downstream of the halogenation reactor (1) and upstream of the separation system (2), and is connected, preferably fluidly connected, to the halogenation reactor (1) and the separation system (2), for example, via a connecting line.

[0474] In some embodiments, C 2+ The alkyl monohalide removal unit may include, for example

[0475] a separation system, such as a separation (eg, distillation) column, configured to receive the effluent stream from the halogenation reactor (1) and to separate C from the effluent stream; 2+ Alkyl monohalide stream,

[0476] a supply system, such as a supply line or pipeline, configured to supply the effluent stream from the halogenation reactor (1) to the separation system, and

[0477] -C 2+ An alkyl monohalide recovery system, such as an outlet line or pipeline, configured to extract the alkyl monohalide from the C 2+ Alkyl separation system collects C 2+ Alkyl monohalide stream.

[0478] C 2+The alkyl monohalide removal unit preferably further comprises means, such as a transfer line or pipeline, for collecting a product stream (e.g., a product stream comprising methyl halide and hydrogen halide) from which the C 2+ Preferably, such an apparatus is configured to transfer the recovered product stream to a downstream separation system to further separate the product stream, for example into a separate methyl halide stream and a separate hydrogen halide stream.

[0479] In some embodiments of the present invention, the system further comprises

[0480] a supply line (18) configured to supply a regenerant as defined herein to the hydroxylation reactor (3), said regenerant being capable of converting the metal halide (MX) formed in said hydroxylation reactor into a metal hydroxide (MOH) and a halogen reactant (X 2 );

[0481] an outlet line (19) configured to remove from the hydroxylation reactor the halogen-containing reactant (X) produced during the conversion reaction; 2 )'s effluent stream.

[0482] By providing the above named elements, the present system enables the regeneration (harvesting) of solid metal hydroxide within the same system. This avoids the need for a delivery system for supplying fresh solid metal hydroxide to the system and process, and thus also improves process sustainability and efficiency.

[0483] Optionally, the system of the present invention may be further provided with a separation device for separating the halogen reactant from the halogen reactant (X) produced during the conversion (regeneration) reaction. 2 ) of the effluent stream. Suitable separation devices for separating the halogen reactant from the effluent stream may include, but are not limited to, one or more condensers.

[0484] In some preferred embodiments, the system further provides a device (19, 20) for returning the logistics of the halogen reactant collected from the hydroxylation reactor (3) to the halogenation reactor (1). In some preferred embodiments, the device (19) for returning the halogen reactant collected from the hydroxylation reactor (3) to the halogenation reactor (1) includes one or more connecting pipelines (connecting pipes). In some embodiments, the one or more connecting pipelines for returning the logistics of the halogen reactant to the halogenation reactor may be provided with one or more dryers (e.g., molecular sieves, etc.), which are suitable for drying the logistics of the halogen reactant before feeding the logistics to the halogenation reactor. In some embodiments, the one or more connecting pipelines for returning the logistics of the halogen reactant to the halogenation reactor may be provided with one or more purification devices (such as, for example, one or more condensers), which are suitable for purifying the logistics of the halogen reactant before feeding the logistics to the halogenation reactor.

[0485] In some embodiments of the present invention, unreacted methane may remain present in the effluent stream obtained in step b) of the process. In some embodiments of the present invention, unreacted methane may remain present in the methyl halide stream obtained in step c) of the process. In some embodiments of the present invention, unreacted methane may remain present in the methanol stream obtained in steps d) and / or f) of the present process. The remaining unreacted methane may be removed from the corresponding stream, for example by distillation. Therefore, the present system further provides the following apparatus: such as a distillation tower, etc., for removing, preferably distilling, unreacted methane from the above-mentioned stream. In a particularly preferred embodiment of the present invention, the following system is provided: wherein the distillation tower is configured to be fluidically connected to a methanol recovery system (7).

[0486] The following examples are only used to illustrate the present invention, and should not be construed as limiting its scope in any way. Although the present invention is only illustrated in some of its forms, it will be apparent to those skilled in the art that the present invention is not limited thereto, but is susceptible to various changes and modifications without departing from the scope of the present invention.

[0487] Example

[0488] Example 1

[0489] refer to Figure 1 , the following examples illustrate embodiments of processes according to the present invention, as well as systems for carrying out such embodiments according to the present invention.

[0490] Figure 1 The system shown in FIG. 1 comprises a halogenation reactor (1), a separation system (2), a hydroxylation reactor (3) and an electrolysis unit (4).

[0491] According to this embodiment, a gaseous feed stream comprising methane is introduced into the halogenation reactor (1) via a feed stream supply line (5). The halogen reactant (e.g. Br 2 ) is also introduced into the halogenation reactor (1) through a separate halogen reactant supply line (6). The gaseous feed stream containing methane and the halogen reactant (X 2 ) reacts in a halogenation reactor to produce an effluent stream comprising methyl halide (MeX) and hydrogen halide (HX). Optionally, unreacted methane remains in the effluent stream.

[0492] The effluent stream obtained leaves the halogenation reactor (1) through a suitable collection pipeline (10) and is fed to a separation system (2) arranged downstream of the halogenation reactor via the pipeline. In the separation system, the effluent stream is further separated into a hydrogen halide (HX) stream and a methyl halide (MeX) stream; the hydrogen halide (HX) stream is collected from the separation unit and fed to the electrolysis unit (4) via a suitable connecting pipeline (12), and the methyl halide (MeX) stream is collected from the separation system and fed to the hydroxylation reactor (3) via a suitable connecting pipeline (11).

[0493] In the hydroxylation reactor (3), a methyl halide (MeX) stream reacts with a solid metal hydroxide, thereby forming methanol (MeOH). A stream comprising methanol can be recovered from the hydroxylation reactor (3) via a methanol recovery line (7).

[0494] In the electrolysis unit (4), the hydrogen halide (HX) stream flowing out of the separation system is further decomposed into hydrogen gas (H 2 ) and the halogen reactant (X 2 ) logistics; the hydrogen gas (H 2 ) is removed from the electrolysis unit via an outlet line (8), the halogen reactant (X 2 ) is removed from the electrolysis unit via outlet line (9).

[0495] Example 2

[0496] refer to Figure 2 , the following example illustrates another embodiment of the process according to the present invention, and a system for carrying out such an embodiment according to the present invention.

[0497] Figure 1 The system shown in FIG. 1 includes a halogenation reactor (1), a separation system (2), a hydroxylation reactor (3), an electrolysis unit (4), and a polyhalogenated alkane removal unit (13).

[0498] A stream containing about 100 mol% (CH 4 ) is introduced into the halogenation reactor (1). The halogen reactant (X 2 ), in this case bromine (Br 2 ), is introduced into the halogenation reactor (1) at a rate of about 5274 kg / hr through the halogen reactant supply pipeline (6). The halogenation reactor (1) is maintained at a temperature of about 300-600°C and a pressure of 5 to 30 bar.

[0499] The unreacted methane (CH 4 ), hydrogen halides (HX), methyl halides (MeX), and polyhalogenated alkanes (e.g. CH 2 X 2 ) and fed to a polyhalogenated alkane removal unit comprising a separation column (13). The separation column removes polyhalogenated alkanes (e.g. CH 2 X 2 )(For example, CH 2 Br 2 ) is separated from the effluent stream and polyhalogenated alkanes (e.g., CH 2 X 2 ).

[0500] From the polyhalogenated alkane removal unit (13), a substantially free 2 X 2 ) and then fed to a separation system (2) comprising a quench tower via a connecting line (16). In the quench tower, the residual gas stream is contacted with an aqueous absorbent, specifically a 26.7 wt% aqueous HBr solution in this example, at a flow rate of about 13800 kg / hr. The absorbent captures gaseous hydrogen halide (HX) from the effluent stream, and the resulting solution leaves the separation system (2) as a liquid stream through a hydrogen halide outlet line (12).

[0501] The remaining gaseous stream essentially comprises methyl halide (MeX) and optionally some unreacted methane (CH 4 ), leaves the separation system (2) via outlet line (17) and is fed to the hydroxylation reactor (3). In this example, the hydroxylation reactor (3) is a swing bed reactor filled with potassium hydroxide (MOH (s) ). The hydroxylation reactor (3) is maintained at a temperature of about 100-300°C and at a pressure of 2 to 30 bar.

[0502] In the hydroxylation reactor (3), methyl halide (MeX) is converted into methanol (MeOH), which is reacted with optional unreacted methane (CH 4 ) is collected through a methanol outlet (7). Methanol is produced at a rate of about 740 kg / hr and can be separated from unreacted methane by techniques known in the art, such as distillation using a distillation column.

[0503] The hydrogen halide (HX) liquid stream leaving the separation system is sent via a hydrogen halide outlet line (12) to an electrolysis unit (4), wherein the hydrogen halide (HX) is decomposed into hydrogen gas (H 2 ) and the halogen reactant (X 2 ), in this embodiment, is Br 2 The produced hydrogen gas (H 2 ) can be collected through the hydrogen gas outlet pipeline (8) and optionally dried. The produced halogen reactant (X 2 ) can also be collected via outlet line (9), optionally dried, and returned to the halogenation reactor (1) for reuse.

[0504] According to the present process, the reactant (in this example potassium hydroxide (MOH (s)) ) is depleted, that is, too much (MX (s) In such a case, the reactor bed can be regenerated by treatment with a regeneration agent (18) comprising air (comprising O 2 and N 2 ) and steam (including H 2 O). This regeneration process results in the formation of metal hydroxide (MOH) and halogen reactant (X 2 ).

[0505] The gaseous effluent produced during such a regeneration process contains nitrogen (N 2 ), trace amounts of unreacted steam, oxygen (O 2 ) and halogen reactant (X 2 ) and can leave the hydrogenation reactor (3) via the effluent outlet (19). Then, the halogen reactant (X 2 ) can be separated from the effluent, for example by condensation, dried, and returned to the halogenation reactor (1) for reuse in the system.

[0506] Example 3

[0507] This example illustrates a halogenation step that can be used in the process of the present invention.

[0508] In this example, the experimental setup consisted of a quartz reactor and a glass syringe (SigmaAldrich) for liquid bromine supply. A methane (5.0, Praxair) supply with a Bronkhorst mass flow controller was established.

[0509] The feed rate was maintained so that the reactants had a residence time of about 0.01 seconds in the heated zone of the reactor and a CH 4 / Br 2 The heating zone of the reactor was maintained at a temperature of about 370° C. and a pressure of about 3 bar.

[0510] The effluent from the reactor was then first passed through a cold trap (10°C) to condense the CH produced during the reaction. 2 Br 2 and trace amounts of unreacted bromine.

[0511] In this experiment, the effluent from the reactor was passed through an aqueous caustic bubbler to remove the major amount of HBr, and the remaining stream was then sent to an Agilent GC with a SilicaPlot column and a FID detector for analysis.

[0512] Based on the GC data, the conversion of methane to methyl bromide (byproduct is CH 2 Br 2 ):

[0513]

[0514]

[0515]

[0516] x(CH 4 ) = 29%,

[0517] s(CH 3 Br) = 89%,

[0518] s(CH 2 Br 2 )=9%.

[0519] Where n = molar mass, x = conversion, and s = selectivity

[0520] Example 4

[0521] The following examples illustrate hydroxylation reaction steps that can be used in the process of the present invention.

[0522] In this example, the experimental setup included the use of a vertical quartz reactor (20 mm ID) connected to a GC. Methyl bromide (>99.9%, Mebrom) was fed via a piston pump. The reactor was filled with 200 grams of potassium hydroxide deposited on porous silica. The temperature of the reactor was maintained at 120°C and 5.5 bar throughout the experiment. During the experiment, 25 g / h of CH 3 The flow rate of Br and N was 280 mL / min. 2 During the 4-hour run, CH 3 The conversion of Br to methanol appears to be stable.

[0523] Based on the GC data, the conversion of methyl bromide to methanol was calculated using the following formula:

[0524]

[0525]

[0526] Where x(CH 3 Br) is higher than 95%, and s (CH 3 OH)=92%;

[0527] Where n = molar mass, x = conversion, and s = selectivity

Claims

1. A process for producing methanol (MeOH) and hydrogen (H2) from methane, comprising the following steps: a) providing a gaseous feed stream comprising methane; b) reacting the gaseous feed stream with at least one halogen reactant (X2) under reaction conditions effective to produce an effluent stream comprising methyl halide (MeX), hydrogen halide (HX), optionally polyhalogenated alkane, and optionally unreacted methane; c) separating from the effluent stream obtained in step b) the following: i) a methyl halide (MeX) stream, optionally comprising unreacted methane; and, ii) hydrogen halide (HX) stream; d) mixing the methyl halide (MeX) stream separated in step c) with a solid metal hydroxide (MOH (s) ) under reaction conditions effective to produce a metal halide (MX) and methanol (MeOH); and, e) decomposing the hydrogen halide (HX) stream separated in step c) by electrolysis under conditions effective to produce a gaseous hydrogen (H2) stream and a stream comprising a halogen reactant (X2).

2. The process according to claim 1, wherein the process further comprises the step of separating the polyhalogenated alkanes formed in step b) from the effluent stream.

3. The process according to claim 2, wherein the step of separating the polyhalogenated alkanes is performed before separating the methyl halide (MeX) stream and the hydrogen halide stream from the effluent stream.

4. A process for producing methanol (MeOH) and hydrogen (H2) from methane according to any one of claims 1 to 3, comprising the following steps: a) providing a gaseous feed stream comprising methane; b) reacting the gaseous feed stream with at least one halogen reactant (X2) under reaction conditions effective to produce an effluent stream comprising methyl halide (MeX), hydrogen halide (HX), polyhalogenated alkanes, and optionally unreacted methane; c) separating from the effluent stream obtained in step b) the following: i) a methyl halide (MeX) stream, which optionally comprises unreacted methane; ii) a hydrogen halide (HX) stream; and, iii) a polyhalogenated alkane stream; d) mixing the methyl halide (MeX) stream separated in step c) with a solid metal hydroxide (MOH (s) ) under reaction conditions effective to produce a metal halide (MX) and methanol (MeOH); and, e) decomposing the hydrogen halide (HX) stream separated in step c) by electrolysis under conditions effective to produce a gaseous hydrogen (H2) stream and a stream comprising a halogen reactant (X2).

5. The process according to any one of claims 1 to 4, wherein the polyhalogenated alkanes comprise polyhalogenated methane and optionally polyhalogenated C 2+ Alkane.

6. A process according to any one of claims 1 to 5, wherein the halogen reactant is selected from bromine (Br2), chlorine (Cl2), fluorine (F2), iodine (I2) and astatine (At2).

7. A process according to any one of claims 1 to 6, wherein the halogen reactant is bromine (Br2).

8. The process according to any one of claims 1 to 7, wherein in step c), a hydrogen halide (HX) stream is separated from the effluent stream by contacting the effluent stream comprising the hydrogen halide with an aqueous absorbent, thereby forming an aqueous hydrogen halide (HX) stream.

9. The process of claim 8, wherein the aqueous absorbent is an aqueous hydrogen halide (HX) solution.

10. The process according to any one of claims 1 to 9, wherein C 2+ The alkyl monohalide is formed in step b).

11. The process according to any one of claims 1 to 10, wherein the process comprises separating the C formed in step b) of the process from the effluent stream. 2+ Alkyl monohalide step.

12. The process according to claim 11, wherein the process comprises separating the C 2+ formed in step b) from the effluent stream before separating the methyl halide (MeX) stream and the hydrogen halide stream from the effluent stream. 2+ Alkyl monohalides.

13. The process of any one of claims 1 to 12, wherein the gaseous feed stream comprises at least 75.0 vol. % methane, based on the total volume of the gaseous feed stream.

14. The process of any one of claims 1 to 13, wherein the gaseous feed stream comprises at least 99.9 vol. % methane, based on the total volume of the gaseous feed stream.

15. The process according to any one of claims 1 to 14, wherein the gaseous feed stream used in step a) of the process is substantially free of sulphur species.

16. The process according to any one of claims 1 to 15, wherein the gaseous feed stream used in step a) of the process contains less than 1.0 mol% of sulphur species.

17. The process according to any one of claims 1 to 16, wherein the gaseous feed stream used in step a) of the process contains less than 0.00001 mol% of sulfur species.

18. The process according to any one of claims 1 to 17, wherein the solid metal hydroxide (MOH (s) ) is a metal hydroxide provided on a solid support.

19. The process of claim 18, wherein the solid support is a silica or alumina support.

20. The process according to any one of claims 1 to 19, wherein the process further comprises the following steps: f) regenerating the metal halide (MX) into a metal hydroxide (MOH) and a halogen reactant (X2), thereby forming a metal hydroxide (MOH) and a halogen reactant (X2).

21. The process according to claim 20, wherein step (f) is carried out by contacting the metal halide (MX) with steam and oxygen (O2) or air.

22. The process according to any one of claims 1 to 21, further comprising the step of returning the halogen reactant (X2) obtained in step e) and / or step f) of the process to step b).

23. The process according to any one of claims 1 to 22, wherein the gaseous hydrogen (H2) stream produced in step e) comprises at least 90.0 mol% hydrogen.

24. The process according to any one of claims 1 to 23, wherein the gaseous hydrogen (H2) stream produced in step e) comprises at least 99.9 mol% hydrogen.

25. The process according to any one of claims 1 to 24, wherein the process further comprises the step of removing unreacted methane from the methanol produced in step d).

26. The process according to claim 25, wherein removing unreacted methane from the methanol produced in step d) is distilling unreacted methane from the methanol produced in step d).

27. The process according to claim 25 or 26, wherein the process further comprises the step of recycling or feeding the removed unreacted methane into step a) and / or step b) of the process.

28. A system for producing methanol (MeOH) and hydrogen (H2) from methane, comprising: - a halogenation reactor (1) configured to react a gaseous feed stream comprising methane with at least one halogen reactant (X2) to form an effluent stream comprising methyl halide (MeX) and hydrogen halide (HX) and optionally unreacted methane, - a separation system (2) fluidly connected to the halogenation reactor (1) and configured to receive an effluent stream from the halogenation reactor (1) and configured to separate a hydrogen halide (HX) stream and a methyl halide (MeX) stream from the effluent stream; a hydroxylation reactor (3) fluidically connected to the separation system (2) and configured to receive a methyl halide (MeX) stream from the separation system (2) and to react the methyl halide (MeX) stream with a solid metal hydroxide (MOH (s) ) reacts to form metal halide (MX) and methanol (MeOH); and - an electrolysis unit (4) comprising at least one electrolysis cell and a power source for supplying electric current to the electrolysis cell, the electrolysis cell being fluidically connected to the separation system (2) and configured to receive a hydrogen halide (HX) stream and to decompose the hydrogen halide (HX) stream into a gaseous hydrogen (H2) stream and a stream comprising a halogen reactant (X2); - a feed stream supply system (5) for supplying a gaseous feed stream comprising methane to the halogenation reactor (1); - a halogen supply system (6) for supplying a halogen reactant (X2) to the halogenation reactor (1); - an effluent collection system (10) configured to collect an effluent stream from the halogenation reactor (1) and feed the collected effluent stream to the separation system (2); - a methanol recovery system (7) configured to recover a stream comprising methanol (MeOH) from the hydroxylation reactor (3); - a hydrogen recovery system (8) configured to recover a gaseous hydrogen (H2) stream from the electrolysis unit (4); - a halogen recovery system (9) configured to recover the halogen reactant (X2) from the electrolysis unit (4); - a hydrogen halide transfer system (12) configured to collect a hydrogen halide (HX) stream from the separation system (2) and supply the collected hydrogen halide (HX) stream to the electrolysis unit (4); - a methyl halide transfer system (11) configured to collect a methyl halide (MeX) stream from the separation system (2) and supply the collected methyl halide (MeX) stream to the hydroxylation reactor (3).

29. The system according to claim 28, wherein the system further comprises an absorbent supply line (17) for supplying aqueous absorbent to the separation system (2).

30. The system of claim 29, wherein the aqueous absorbent is an aqueous hydrogen halide (HX) solution.

31. The system according to any one of claims 28 to 30, wherein the system further comprises a polyhalogenated alkane removal unit configured to receive the effluent stream from the halogenation reactor (1) and remove polyhalogenated alkanes from the effluent stream.

32. The system according to any one of claims 28 to 31, wherein the system further comprises C 2+ an alkyl monohalide removal unit configured to receive an effluent stream from the halogenation reactor (1) and remove C 2+ Alkyl monohalides.

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