EA017229B1 - Process for converting hydrocarbon feedstocks with electrolytic recovery of halogen - Google Patents

Abstract

An improved continuous process for converting methane, natural gas, and other hydrocarbon feedstocks into one or more higher hydrocarbons, methanol, amines, or other products comprises continuously cycling through hydrocarbon halogenation, product formation, product separation, and electrolytic regeneration of halogen, optionally using an improved electrolytic cell equipped with an oxygen depolarized cathode.

Description

Field of Invention

The present invention relates to a method for converting natural gas and other types of hydrocarbon feeds into more valuable products such as fuel hydrocarbons, methanol and aromatics.

BACKGROUND OF THE INVENTION

US Patent Application No. 11/703358 (hereinafter, Application 358), entitled Continuous Conversion of Natural Gas to Liquid Hydrocarbons, filed February 5, 2007, based on provisional patent application US No. 60/765115, filed February 3, 2006. , describes a continuous process for reacting molecular halogen with a hydrocarbon feed to produce higher hydrocarbons. In one embodiment, the method includes the steps of halogenating alkanes, reproporting polyhalogenated compounds to increase the amount of monohalides formed, oligomerizing (CC addition) of alkyl halides to form products with a large number of carbon atoms in the molecules, separating the products from hydrogen halide, continuous halogen regeneration and molecular halogen recovery out of the water. Hydrohalic acid (e.g. HBg) is separated from liquid hydrocarbons in a liquid-phase separator and then converted to molecular halogen (e.g. bromine) by reaction with an oxygen source in the presence of a metal oxide catalyst. Application 358 is fully incorporated into this description by reference.

Application 358 proposes a significant improvement in the prior art process for the activation of CH bonds and industrial processes for converting hydrocarbon feeds into more valuable products. The present invention is based on application 358, which proposes the use of electrolysis for the regeneration of molecular halogen (e.g., Br ₂ , Cl ₂ ) from hydrohalic acid (e.g., HBr, HC1).

The electrolysis of aqueous solutions with the release of hydrogen and oxygen is a known way of producing hydrogen using electrical energy. Similarly, halogens are released during the electrolysis of metal halide solutions or metal halide vapors. The traditional method of industrial production of hydrogen is based on the reforming of hydrocarbons with water (water vapor) to produce carbon monoxide and molecular hydrogen:

СН) + Н ₂ О -> СО + ЗН ₂ ΔΗ = +206 kJ / mol

С _X Н _У + хН ₂ О - хСО + (х + у / 2) Н ₂ ΔΗ »0 kJ / mol.

The energy-disadvantageous reforming reaction can be compared with the complete exothermic oxidation of hydrocarbons in oxygen with the formation of low-energy products - water and carbon dioxide:

CH) + 2O ₂ -s CCL + 2H ₂ O ΔΗ = -882 kJ / mol

С ' _х Г1 _у + (х + у / 2) О ₂ -> хСО ₂ + у / 2Н ₂ О ΔΗ

As a rule, the reforming process is carried out in conjunction with complete oxidation to produce the energy needed to undergo another endothermic reaction. The resulting total reaction produces carbon oxides, and hydrogen, and can be operated almost isoenergetically:

С „Н _t + хО ₂ + уН ₂ О -" (п-т) СО + tСОg + (t / 2 + y) Н ₂ .

Alternatively, hydrogen can be obtained by dissociating water:

Н ₂ О - * 1 / 2О ₅ + Н ₂ ΔΗ = 286 kJ / mol Н ₂ .

Despite the fact that the reaction is energetically disadvantageous, it can be carried out by electrolysis using an amount of electricity of 2x10 ⁵ C / g-mol of H ₂ . Water is a source of both hydrogen and oxygen, and the high activation energy during oxygen generation requires overvoltages of approximately 1.6 V and stoichiometric current. In practice, the required electrical energy is approximately 300 kJ / mol H ₂ .

When producing halogen by electrolysis of halide salts, for example, in a chlor-alkali process, in an aqueous salt solution (No. C1), halogen (C1 ₂ ) and alkali (ΝαΟΗ) are obtained from the halide anion and water. Once again, water is the source of hydrogen. Similarly, bromide can be obtained from bromide salts (Ν; · ιΒγ). In the latter case, the formation of molecular halogen from the halide anion is energetically and kinetically favorable in comparison with the formation of oxygen, since it requires less overvoltage (1.1 V compared to 1.6 V):

H, 0 + CaBr - * Br ₂ + H ₂ + MaOH.

when the amount of electricity is 2x10 ⁵ C / g-mol H ₂ and a significant reduction in the amount of required electricity (compared with pure H ₂ O) is up to approximately 200 kJ / g-mol H ₂ .

- 1 017229

Many attempts have been made to develop economically viable hydrogen production methods. In principle, direct electrochemical oxidation of hydrocarbons with oxygen (as in a solid oxide fuel cell) and / or water with the formation of hydrogen is possible; nevertheless, this path leads, as a rule, to the formation of complex, difficult to separate intermediate products and is not cost-effective. Another method for removing hydrogen from hydrocarbons is the phased partial oxidation with halogen (preferably bromine). The main advantage is that complete oxidation of the hydrocarbon to carbon dioxide cannot occur, and hydrogen passes into a less stable HBr (AN _formation = -36 kJ / mol) than water ^ formation ^{286 kJ / mol)} .

ScN _w + r / 2Vg _g - "SpNifVgr + pHVg

SpNgVc + x / 2Vg ₂ C „N _g Br _r + xNVg.

The final products remaining after removal of HBr depend on the reaction conditions and may consist of mixtures of coke and brominated and perbrominated hydrocarbons. C _x + C _y H _i Br ₁ + C _g Br _h The burning of these end products in an oxygen atmosphere containing trace amounts of water can be used to generate heat and produce carbon oxides and convert residual bromine to HBg

Cx - · - C _y H ₂ Br, + CrBr _i + n / 2O ₂ + (ί + ς) / 2Η ₂ Ο -> (x + y + r = n) CO ₂ + (1 + q) HBr.

Another method of producing hydrogen, based on the electrolysis of HBr, according to available data allows you to save about 25% of energy compared to electrolysis of water. However, in this process, it is necessary to convert the bromine obtained during electrolysis back to HBr, and this conversion step is the main disadvantage of receiving HBr electrolysis to hydrogen. In contrast, the present invention uses bromine generated during the electrolysis process to produce valuable products, rather than simply converting it back to HBr.

SUMMARY OF THE INVENTION

The present invention combines the thermal (non-electrochemical) ability of halogens (preferably bromine) to react with hydrocarbons to produce hydrogen halide (preferably HBg) and reactive alkyl halides or other carbon-containing intermediates that can be converted into subsequent products more easily than the starting hydrocarbon with simple electrolysis of hydrogen halides or halide salts, creating a common process with significantly higher efficiency. The use of halogens prevents the complete oxidation of hydrocarbons to carbon dioxide and allows the sequentially production of partially oxidized products.

In one aspect of the invention, a continuous process for converting a hydrocarbon feed to one or more higher hydrocarbons includes.

(a) the formation of alkyl halides by reacting molecular halogen with a hydrocarbon feed under process conditions sufficient to form alkyl halides and hydrogen halide, preferably with substantially complete consumption of molecular halogen;

(b) the formation of higher hydrocarbons and hydrogen halide by contacting the alkyl halides with the first catalyst under process conditions sufficient to form higher hydrocarbons and hydrogen halide;

(c) separating higher hydrocarbons from hydrogen halide;

(ά) electrolytic conversion of hydrogen halide to hydrogen and molecular halogen, whereby this halogen can be reused;

(e) repeating steps (a) to (ά) the desired number of times.

These steps can be carried out in this order or, alternatively, in a different order. Electrolysis is carried out in aqueous media or in the gas phase. Optionally, alkyl halides are disproportionated by reacting some or all of the alkyl halides with a feed stream of alkanes, while the fraction of monohalogenated hydrocarbons present increases. In addition, in some embodiments, the hydrogen obtained in this process is used to generate energy.

In a second aspect of the invention, a continuous process for converting a hydrocarbon feed to methanol comprises.

(a) the formation of alkyl halides by reacting molecular halogen with a hydrocarbon feed under process conditions sufficient to form alkyl halides and hydrogen halide, preferably with substantially complete consumption of molecular halogen;

(b) the formation of methanol and an alkali metal halide by contacting the alkyl halides with an aqueous alkali solution under process conditions sufficient to form methanol and an alkali metal halide;

(c) separating methanol from an alkali metal halide;

(ά) electrolytic conversion of an alkali metal halide to hydrogen or molecular halogen and an aqueous alkali solution, whereby halogen and alkali can be used repeatedly

- 2 017229 but;

(e) repeating steps (a) to (i) the desired number of times.

These steps can be carried out in this order or, alternatively, in a different order. Optionally, polyhalogenated hydrocarbons are disproportionated when some or all of the alkyl halides are reacted with a feed stream of alkanes, while the fraction of monohalogenated hydrocarbons present increases.

Obtaining methanol in this way requires that the reaction of alkyl halides with an aqueous solution of alkali be carried out under alkaline conditions. However, the electrolysis process gives alkali and acid in stoichiometrically equivalent amounts. Thus, a simple re-combination of all alkali with all acid would lead to the formation of a neutral solution. The method described herein provides for the disproportionation of acid and base, so that alkali is available in more than enough amount to react with alkyl bromides to achieve alkaline conditions. The acid removed in the disproportionation step is later re-combined with an excess of alkali after methanol and other products have been obtained and separated.

In some embodiments, it may be necessary to maintain the anolyte under acidic conditions, which may require the addition of a small amount of acid. The separation of part of the acid can be carried out by means of a liquid phase process or, alternatively, by means of a regenerable solid reagent or adsorbent. In addition, it is possible to introduce acid from an external source generated either locally or remotely. Alternatively, a total excess of acid can be achieved by removing a small amount of alkali from the system.

In a third aspect of the invention, a continuous process for converting a hydrocarbon feed to an alkylamine comprises:

(a) the formation of alkyl halides by reacting a molecular halogen with a hydrocarbon feed under process conditions sufficient to form alkyl halides (e.g. ethyl bromide) and hydrogen halide, preferably at substantially complete consumption of molecular halogen;

(b) the formation of alkyl amines and an alkali metal halide by contacting the alkyl halides with ammonia or aqueous ammonia under process conditions sufficient to form alkyl amines and an alkali metal halide;

(c) separating alkyl amines from an alkali metal halide;

(i) electrolytic conversion of an alkali metal halide to hydrogen and molecular halogen, whereby the halogen can be reused;

(e) repeating steps (a) to (i) the desired number of times.

These steps can be carried out in this order or, alternatively, in a different order. Optionally, alkyl halides are disproportionated by reacting some or all of the alkyl halides with a feed stream of alkanes, while the fraction of monohalogenated hydrocarbons present increases.

In a fourth aspect of the invention, there is provided a continuous process for converting coal to coke and hydrogen, comprising:

(a) the formation of brominated intermediate processing products of coal and hydrogen halide during the reaction of crushed coal with molecular halogen under process conditions sufficient for bromination and dissociation of the main elements of the skeleton of the coal, thereby forming a mixture of brominated intermediate processing products of coal (e.g. polybrominated hydrocarbons);

(b) the formation of coke and hydrogen halide in the reaction of brominated intermediate products of coal processing on the catalyst under process conditions sufficient to form coke and hydrogen halide;

(c) separating coke from hydrogen halide;

(i) electrolytic conversion of the hydrogen halide formed in stage (a) and / or stage (b) into hydrogen and molecular halogen, whereby the halogen can be reused;

(e) repeating steps (a) to (i) the desired number of times.

These steps can be carried out in this order or, alternatively, in a different order. The obtained coke can be used to generate electricity necessary for the process (through combustion, generation of water vapor and electricity generation), or collected and put on sale.

- 3 017229

In a fifth aspect of the invention, there is provided a continuous process for converting coal or hydrocarbons obtained from biomass into polyols and hydrogen, comprising:

(a) the formation of alkyl halides by reacting molecular halogen with coal or a hydrocarbon feed obtained from biomass under process conditions sufficient to form alkyl halides and hydrogen halide, preferably with substantially complete consumption of molecular halogen;

(b) the formation of polyols and an alkali metal halide by contacting the alkyl halides with an aqueous alkali solution under process conditions sufficient to form polyols and an alkali metal halide;

(c) separating polyols from an alkali metal halide;

(b) electrolytic conversion of an alkali metal halide to hydrogen and molecular halogen, whereby the halogen can be reused;

(e) repeating steps (a) to (b) the desired number of times.

These steps can be carried out in this order or, alternatively, in a different order. Optionally, alkyl halides are disproportionated by reacting some or all of the alkyl halides with a feed stream of alkanes, while the fraction of monohalogenated hydrocarbons present increases.

In one important embodiment of the invention, an oxygen depolarization electrode is used in the electrolyzer, wherein the electrolysis of hydrogen halide gives molecular halogen and water, and the electrolysis of an alkali metal halide gives molecular halogen and alkali metal hydroxide, rather than hydrogen. The advantage of this implementation option is to significantly reduce the energy consumption of the electrolytic cell (s). According to yet another aspect of the invention, there is also provided an improved electrolytic cell equipped with an oxygen depolarization electrode.

Various aspects of the invention have a number of common elements, including: (1) halogenation of a hydrocarbon feed in the presence of molecular halogen to produce hydrogen halide and an oxidized carbon-containing product; (2) the subsequent reaction of the oxidized carbon-containing products to obtain the final products; (3) separating carbon-containing products from bromine-containing components; (4) electrolysis of the remaining halogen-containing components (e.g. HBg, No. 1Bg) to form halogen and hydrogen in the electrolytic cell (or, alternatively, using an oxygen depolarization electrode to produce halogen and water or halogen and alkali metal hydroxide instead of hydrogen). The resulting hydrogen can be used to power one or more process components, or compressed and put up for sale.

The currently used commercial process for the processing of methane, coal and other hydrocarbons produces synthesis gas (CO + H ₂ ), which can be converted into more valuable products, such as methanol and linear alkanes. The production of intermediate synthesis gas is extremely expensive, and the production of useful products requires the restoration of almost completely oxidized carbon. The present invention in many aspects surpasses the traditional process involving synthesis gas and has at least the following advantages.

The use of alkyl halide intermediates to produce more valuable products, including fuels and more valuable chemicals.

Decrease in working pressure (for example, ~ 1-5 atm against ~ 80 atm).

Decrease in the maximum working temperature (for example, ~ 50 ° C against ~ 1000 ° C).

No need for pure oxygen.

The lack of a reformer with fire heating, which increases safety when used on offshore platforms.

Simplified reactor design compared to a complex converter of synthesis gas to methanol.

No need for a catalyst, unlike the catalysts needed for reforming and for converting synthesis gas.

Reduced by-products, which facilitates methanol purification operations.

No need to supply steam for reforming.

Hydrogen production on a separate electrode as a relatively pure product.

Bringing the reaction to completion in the last step by removing products from the reaction vessel.

According to the invention, the molecular halogen used to form the alkyl halides is recovered as hydrogen halide and returned to the electrolytic cell, and the alkyl halides are converted into more valuable products. Examples include the conversion of methyl bromide to aromatics and HBg on a zeolite catalyst, as well as the conversion of monoalkyl bromides (e.g. ethyl bromide) to olefins (e.g. ethylene) and HBg on a catalyst. Alternatively, alkyl halides are readily converted to oxygenates such as alcohols, ethers and aldehydes. Examples include the conversion of methyl bromide to methanol and NaBr in an aqueous Να раство solution, as well as the conversion of dibromomethane to ethylene glycol and No. 1Br to ΝαΟΗ. In yet another embodiment, the alkyl halides are readily converted to

- 4 017229 amines. Examples include the conversion of bromobenzene to phenol and aniline in aqueous ammonia, as well as the conversion of ethyl bromide in ammonia to ethylamine and # 1 Br.

The invention finds practical application in industrial facilities for the extraction of oil or gas, such as offshore oil or gas drilling rig or wellhead located on land. The continuous methods described herein can be used in combination with oil and / or gas production using electricity generated locally to power an electrolytic cell (s).

Brief Description of the Drawings

Various features, embodiments, and advantages of the invention will be more apparent when considered in view of the detailed description of the invention, as well as when referring to the accompanying drawings, which show:

in FIG. 1 is a schematic diagram of a continuous process for converting hydrocarbon feedstocks to higher hydrocarbons according to one embodiment of the invention;

in FIG. 2 is a schematic diagram of a continuous process for converting hydrocarbon feedstocks to higher hydrocarbons according to another embodiment of the invention;

in FIG. 3 is a schematic diagram of a continuous process for converting hydrocarbon feedstocks to methanol according to one embodiment of the invention, in which a membrane type electrolytic cell is used to regenerate molecular bromine;

in FIG. 4 is a schematic diagram of a continuous process for converting hydrocarbon feedstocks to methanol according to another embodiment of the invention, in which a diaphragm type electrolytic cell is used to regenerate molecular bromine;

in FIG. 5 is a schematic diagram of a continuous process for converting hydrocarbon feedstocks to higher hydrocarbons, in which an oxygen depolarization cathode is provided, according to one embodiment of the invention;

in FIG. 6 is a schematic illustration of an electrolytic cell according to one embodiment of the invention;

in FIG. 7 is a schematic illustration of a continuous process for converting coal to coke and hydrogen according to one embodiment of the invention;

in FIG. 8 is a schematic illustration of a method for converting coal or biomass into polyols and hydrogen according to one embodiment of the invention;

in FIG. 9 is a product distribution diagram illustrating methane bromination selectivity according to one embodiment of the invention;

in FIG. 10 is a product distribution diagram illustrating methyl bromide condensation selectivity according to one embodiment of the invention;

in FIG. 11 is a product distribution diagram illustrating methyl bromide condensation selectivity according to another embodiment of the invention.

DETAILED DESCRIPTION OF THE INVENTION

The present invention provides a chemical method for the conversion of various types of hydrocarbon feedstocks to more valuable products, such as fuel hydrocarbons, methanol, aromatics, amines, coke and polyols, using molecular halogen to activate CH bonds in the feed and electrolysis to convert formed during the process of hydrogen halide (hydrogen halide) or halide salts (e.g. sodium bromide) back to molecular halogen. Non-limiting examples of hydrocarbon species suitable for use in the present invention include alkanes, for example methane, ethane, propane and even heavier alkanes; olefins; natural gas and other mixtures of hydrocarbons; hydrocarbons derived from biomass; as well as coal. Some refining processes produce streams of light hydrocarbons (the so-called light fractions), usually a mixture of C ₁ -C ₃ hydrocarbons, which, with or without methane, can be used as hydrocarbon feedstocks. With the exception of coal, in most cases, the hydrocarbon feed is primarily aliphatic in nature.

The hydrocarbon feed is converted into more valuable products by reaction with molecular halogen, as described above. Preferred bromine (Br _2), chlorine (C1 _2), and most preferably bromo, partly because the overpotential required for the conversion of Br ^- Br2 in significantly lower than that required to convert a C1 ^- to C12 (1.09 volts for Br ^- against 1.36 V for C1 ^- ). The possibility of using fluorine and iodine is implied, but not necessarily with equivalent results. Some of the problems associated with fluorine can probably be eliminated by using dilute fluorine streams (for example, fluorine gas carried in a stream of helium, nitrogen, or another diluent). Nevertheless, it should be expected that more severe reaction conditions will be required for the condensation of alkyl fluorides to form higher hydrocarbons due to the strength of the fluorine-carbon bond. Similarly, problems associated with iodine (such as the endothermic nature of certain reactions involving iodine) can probably be eliminated by carrying out halogenation and / or condensation reactions at elevated temperatures and / or pressures. In general, bromine or chlorine is preferred, with bromine being most preferred.

- 5 017229

As used herein, the term higher hydrocarbons refers to hydrocarbons containing more carbon atoms than one or more hydrocarbon components, as well as olefinic hydrocarbons containing the same or more carbon atoms than one or more hydrocarbon components. For example, if the hydrocarbon feed is natural gas, it is usually a mixture of light hydrocarbons with a predominance of methane and lower amounts of ethane, propane and butane and even lower amounts of hydrocarbons with a longer carbon chain, such as pentane, hexane, etc. - then the higher (s) hydrocarbon (s) obtained according to the invention may include C ₂ or higher hydrocarbons such as ethane, propane, butane; C ₅ + hydrocarbons; aromatic hydrocarbons, etc .; and optionally longer chain ethylene, propylene and / or olefins. The term light hydrocarbons (sometimes abbreviated to LNSk) refers to C1-C4 hydrocarbons, for example methane, ethane, propane, ethylene, propylene, butanes and butenes, which are usually in a gaseous state at room temperature and atmospheric pressure. Fuel hydrocarbons typically contain 5 or more carbon atoms and are liquids at room temperature.

As in this description, and in the claims, the chemicals mentioned in the plural also include the singular, and vice versa, unless otherwise indicated in the context. For example, the term alkyl halides includes one or more alkyl halides, which may be the same (eg, 100% methyl bromide) or different (eg, methyl bromide and dibromomethane); the term higher hydrocarbons includes one or more higher hydrocarbons, which may be the same (for example, 100% octane) or different (for example, hexane, pentane and octane).

FIG. 1-5 are schematic diagrams of technological operations generally reflecting various embodiments of the invention in which hydrocarbons are allowed to react with molecular halogen (eg, bromine) and are converted into one or more more valuable products. In FIG. 1 shows one embodiment of a method for producing higher hydrocarbons from natural gas, methane or other light hydrocarbons. Hydrocarbon feeds (for example, natural gas) and molecular bromine are transferred via separate lines 1, 2 to the bromination reactor 3 and are allowed to react there. Products (HBr, alkyl bromides, possibly olefins) and, possibly, unreacted hydrocarbons exit the reactor and are transferred via line 4 to condensation reactor 5 to form carbon-carbon bonds (carbon-carbon addition). Optionally, the alkyl bromides are first sent to a separation unit (not shown) where the monobrominated hydrocarbons and HBg are separated from the polybrominated hydrocarbons, the latter being transferred back to the bromination reactor for reporportation with methane and / or other light hydrocarbons, as described in application 358.

In the condensation reactor 5, monobromides and possibly other alkyl bromides and olefins react in the presence of a condensation catalyst to form higher hydrocarbons. Non-limiting examples of condensation catalysts are presented in application 358, paragraphs 61-65. The preparation of doped zeolites and their use as catalysts for the formation of carbon-carbon bonds is described in patent publication No. I8 2005/0171393 A1 on p. 4-5, incorporated herein by reference in its entirety.

HBg, higher hydrocarbons and (possibly) unreacted hydrocarbons and alkyl bromides exit the condensation reactor and are transferred via line 6 to the hydrogen bromide absorption unit 7, where the hydrocarbon products are separated from HBg by absorption, distillation and / or another suitable separation method. Hydrocarbon products are diverted via line 8 to a product recovery unit 9, in which products — higher hydrocarbons, are separated from residues of natural gas or other gaseous substances, which are vented through line 10 or, in the case of natural gas or lower alkanes, are recycled and transferred back to bromination reactor. Alternatively, flammable substances can be sent to the energy block and used to generate heat and / or electricity to power the system.

Aqueous sodium hydroxide or other alkali is transferred via line 11 to the HBg absorption unit, where HBg is neutralized and aqueous sodium bromide is formed. Aqueous sodium bromide, together with small amounts of hydrocarbon products and other organic substances, is transferred via line 12 to a separation unit 13 in which organic components are separated from sodium bromide by distillation, liquid phase extraction, flash evaporation or other suitable method. The organics is either removed from the system to the separation unit for the separation of products, or in the shown embodiment, returned to the HBg absorption unit 7 via line 14 and finally removed from the system via line 8.

The aqueous sodium bromide is transferred from the IABr-organic separation unit 13 via line 15 to the electrolytic cell 16 with the anode 17 and the cathode 18. The system is equipped with a supply line 19 for adding water, additional electrolyte and / or acid or alkali to adjust the pH. As a cell, it is more preferable to use a series of electrolytic cells, rather than a single cell. Alternatively, several series of cells can be connected in parallel. Non-limiting

- 6 017229 examples of electrolytic cells include diaphragm, membrane and mercury cells, which may be monopolar or dipolar. The exact material flows in relation to the supplied water, electrolyte and other process characteristics will vary depending on the type of cell used. Aqueous sodium bromide is subjected to electrolysis in an electrolytic cell (s) with oxidation of the bromide ion at the anode (2Br ^- 10Br2 + 2e ^- ) and water reduction at the cathode (2H2O + 2e ^- 10H ₂ + 2OH ^- ). Aqueous sodium hydroxide is removed from the cell and sent to the HBg absorption unit through line 11.

The bromine and hydrogen obtained in the electrolyzer are recovered, while the bromine is recycled and reused in the process. Specifically, wet bromine is transferred through line 20 to desiccant 21, and dry bromine is transferred through line 22 to heater 23, and then back to line 2 to bromination reactor 3. If the amount of water associated with bromine is acceptable during bromination and condensation, the dehumidifier may not be used. The hydrogen obtained at the anode of the electrolytic cell can be withdrawn, or more preferably collected, compressed, and sent via line 24 to an energy block, such as a fuel cell or a hydrogen turbine. Alternatively, the resulting hydrogen may be recovered for sale or other uses. The generated electricity can be used to power various parts of the equipment involved in a continuous process, including electrolytic cells.

Exemplary and preferred conditions (e.g., catalysts, pressure, temperature, residence time, etc.) of bromination, CC condensation, reproportionation, separation of products, purification of HBr, as well as corrosion-resistant materials are presented in application 358 in paragraphs 39-42 ( bromination), 43-50 (reproportionation), 61-65 (CC condensation), 66-75 (separation of products), 82-86 (HBg purification and halogen extraction) and 87-90 (corrosion-resistant materials), and the above paragraphs included in this application in its entirety. Anodes, cathodes, electrolytes and other signs of an electrolytic cell (s) are selected based on a number of factors that are understood by a person skilled in the art, such as productivity, current power levels, and chemical characteristics of the electrolysis reaction (s). Non-limiting examples are presented in US patent No. 4110180 (Νίάοΐα s1 a1.) And 6368490 (Sec1ettapp); Υ. δΐιίιηίζιι. N. Msta, N. Uatahoe, Sak-Ryake E1es1go1uk1k OG Nuigosatos Lai Ikshd RTE-Vopiei E1es1teye, Ιηΐ. 1. Nuigodep Epegdu, Wo1. 13, Νο. 6, 345-349 (1988); Ό. uap UeEep, N. Lapdekpatr, A. MoguoikkeG, R. M111shd1op, HBr E1ec1go1uk18 ίη 1ye 1crack Magk 13A E1ye Sak EekRyiphaiop Prgosek: E1ec1to1uk1k ίη and EEM Sееееее1, 1.. 20, 60-68 (1990); apy 8. Mo1ira11u, Ό. Mack, E. Egepe, 1. ей ет ет ус Рес ус ус ус,, оп оп оп оп оп пе пе пе пе гот,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,, 1998 11 1998 1998 1998 1998 1998 1998 1998 1998 11 11 11 1998 1998 1998 1998 11 1998 1998 1998 1998 1998 11 1998 1998 1998 1998 1998 1998 1998 1998 1998 1998 1998 1998 1998 1998 1998 1998 1998 1998 1998 1998 1998 1998 1998 1998 1998 1998, 1998 11 1998 1998 1998 1998 1998 1998; all publications are incorporated herein by reference in their entirety.

In one embodiment of the invention illustrated in FIG. 1, methane is introduced into an ideal displacement reactor made of AECOY alloy at a rate of 1 mol / s, and molecular bromine is introduced at a rate of 0.50 mol / s, with a total residence time of 60 s at 425 ° C. The main hydrocarbon products include methyl bromide (85%) and dibromomethane (14%), and HBg is also formed at a rate of 0.50 mol / s. The methane conversion is 46%. The products are transferred via line 4 to the condensation reactor 5, which is a packed bed reactor containing an ion-exchange transition metal (e.g., Mn) zeolite condensation catalyst on a 28M5 alumina support at 425 ° C. In the condensation reactor 5, a certain distribution of higher hydrocarbons is formed, which is determined by the spatio-temporal characteristic of the reactor. In this example, 10 s is the preferred time to produce gasoline products. HBg, higher hydrocarbons and unreacted alkyl bromides (trace amounts) exit the condensation reactor and are transferred via line 6 to hydrogen bromide separation unit 7, where HBg is partially separated by distillation. Aqueous sodium hydroxide is introduced and allowed to react at 150 ° C. to form sodium bromide and alcohols from HBr and unreacted alkyl bromides. Aqueous and organic components are transferred via line 12 to a separation unit 13, in which organic components are separated by distillation from sodium bromide. The aqueous sodium bromide is transferred through line 15 from separation unit 13Br organic to the electrolytic cell 16 with the anode 17 and cathode 18. To add water, additional electrolyte and adjust the pH to values less than 2 by adding acid, a supply line is provided 19. Electrolysis is carried out in membrane type cell. Aqueous sodium bromide is subjected to electrolysis in an electrolytic cell with the oxidation of the bromide ion at the anode (2Br ^- siBr2 + 2e ^- ) and the reduction of water at the cathode (2H2O + 2e ^- uH ₂ + 2OH ^- ). Aqueous sodium hydroxide is removed from the cell and sent to the HBg absorption unit through line 11. In the cell, bromine and hydrogen are obtained.

In FIG. 2 shows an alternative embodiment of a method for converting natural gas, methane or other types of hydrocarbon feedstocks to higher hydrocarbons, such as fuel hydrocarbons and aromatics. In this embodiment, electrolysis occurs in a non-alkaline environment. The products from the condensation reactor (i.e. higher hydrocarbons and HBg) are transferred via line 6 to the HBg absorption unit 7, where the hydrocarbon products are separated from the HBg. After the residual organic components are removed from the HBg in the separation unit 13, the enriched aqueous solution of HBg is transferred

- 7 017229 are sown via line 15 to the electrolytic cell 16. Replenishment of water, electrolyte or acid / base to adjust the pH, if necessary, is carried out along line 19. The aqueous HBg solution is electrolyzed to form molecular bromine and hydrogen. With the allocation and removal of Br ₂ from the cell, the concentration of HBr in the cell decreases. The resulting depleted HBg aqueous solution, together with some bromine captured or dissolved in it (Br ₂ ), is transferred via line 25 to the bromine separation column 26, where bromine (Br ₂ ) is separated from the depleted HBg aqueous solution by distillation or other suitable separation operations. The depleted aqueous HBg solution is transferred back to the HBg absorption unit via line 27. Wet bromine is transferred through line 28 to desiccant 21, where it is drained.

In another embodiment of this aspect of the invention (not shown), natural gas, methane, or other hydrocarbon feeds are converted to higher hydrocarbons, and halogen (e.g., Br ₂ ) is recovered by gas-phase electrolysis of hydrogen halide (e.g. HBg). The products from the condensation reactor (i.e. higher hydrocarbons and HBg) are transferred through another line to the HBg absorption unit, where the hydrocarbon products are separated from the HBg. After the residual organic components are removed from the HBg in the separation unit, the gaseous HBg is transferred along another line to the electrolytic cell. Gaseous HBg is subjected to electrolysis with the formation of molecular bromine and hydrogen. Wet bromine is transferred along another line to a desiccant, where it is drained. Optionally, the dehumidifier may not be used if dry HBr is supplied to the electrolysis cells.

In FIG. Figure 3 shows one embodiment of another aspect of the invention in which natural gas, methane or other hydrocarbon feeds are converted to methanol through the methyl bromide intermediate. Natural gas and gaseous bromine are transferred via separate lines 201 and 202 to the bromination reactor 203 and allowed to react. The reaction products (for example, methyl bromide and HBg), as well as possibly unreacted hydrocarbons, are transferred through line 204 through heat exchanger 205, which lowers their temperature. If necessary, the gases are cooled further when passing through a cooler 206. Some of the gases 206 are transferred via line 207 to an absorber 208 HBr. The remainder of the gases bypassing the HBg absorber is transferred via line 209 directly to the reactor / absorber 210. The separation proportions are determined by the acid / alkaline disproportionation necessary to achieve the required pH in the reactor absorber.

Water, possibly pretreated, for example, in reverse osmosis unit 211 to minimize salt content, enters methanol reactor 210 via line 212. In addition, a separate line 213 transfers water to an absorber 208 HBg.

The HBg solution formed in the HBr absorber 208 is sent via line 214 to a separation column 215 (where the organics are separated by distillation or other methods), and then sent to the reactor / absorber 210 via line 216. The gases from the HBg absorber are mixed with the bypass stream from cooler 206 and transferred via line 209 to the reactor / absorber 210. The HBg solution from the separation column 215 is transferred via line 217 to the HBg storage tank 218.

Aqueous sodium hydroxide (for example, 5-30 wt.%) Enters the methanol reactor 210 via line 219. A weak solution of No. 1Bg in water is also supplied to methanol reactor 210 through line 220.

In a methanol production reactor, methyl bromide reacts with water in the presence of a strong base (sodium hydroxide), which forms methanol, along with possible by-products such as formaldehyde or formic acid. A liquid stream containing methanol, by-products, aqueous sodium bromide and aqueous sodium hydroxide is diverted from the reactor via line 221 to a separation column 222. A portion of the bottoms liquid from the reactor / absorber 210 via line 223 is forced to circulate through a cooler 224 to control the temperature in the reactor / absorber 210.

The separation column 222 is equipped with a reboiler 225 and may work with partial reflux. Aqueous sodium bromide and sodium hydroxide are removed together with most of the water as a bottoms stream of a separation column. Vapors from the top of the separation column are transferred via line 226 to another distillation unit 227, equipped with a reboiler 228 and a condenser 229. At distillation unit 227, by-products are separated from methanol, and methanol is removed from distillation unit 227 via line 230, through cooler 231 to storage tank 232. Vapors from distillation unit 227 (containing by-products) are transferred via line 233 through a condenser 229, and then through line 234 to a by-product storage tank 235. Optionally, depending on the specific by-products obtained and their boiling points, methanol can be separated as a distillate, while the by-products are isolated as bottoms.

The effluent removed from the distillation unit 222 and reboiler 225 contains water and aqueous sodium bromide and sodium hydroxide. This stream is diverted from the distillation unit via line 236 and cooled as it passes through cooler 237 before being fed to sodium bromide storage tank 238. It is advisable to lower the pH of this saline solution. This is achieved by measuring the supply of aqueous HBg from the hydrogen bromide storage tank 218 via line 239 to a pH control device 240 connected to a sodium bromide storage tank 238.

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After adjusting the pH of sodium bromide in the storage tank 238 to a desired level (for example, slightly acidic), the aqueous sodium bromide is removed from the tank and transferred via line 241 through a filter 242 and fed to an electrolytic cell 243 with anode 244 and cathode 245. The filter is designed to protect membranes in electrolytic cells. Preferably, a series of electrolytic cells, rather than a single cell, is used as the electrolyzer.

Aqueous sodium bromide is subjected to electrolysis in an electrolytic cell (s) with oxidation of the bromide ion at the anode (2W ^- ^ W2 + 2e ^- ) and water reduction at the cathode (2H2O + 2e ^- ^ H ₂ + 2OH ^- ). This leads to the formation of sodium hydroxide, which is diverted from the electrolyzer in the form of an aqueous solution through line 246 to the storage tank 247. Then, the sodium hydroxide solution is sent to methanol reactor 210 through line 219.

Molecular bromine is withdrawn from the electrolyzer through line 248 to compressor 249, and then to desiccant 250. Bromine is returned to bromination reactor 203 after passing it through heat exchanger 205 and, if necessary, through heater 251. Molecular bromine dissolved in anolyte is also removed from electrolytic cells (cells) 243, transferring the anolyte from the cell (s) along line 252 to a separation column 253 where bromine is removed by distillation with natural gas (fed through line 254) or other methods. Molecular bromine is transferred via line 255 to compressor 249, desiccant 250, etc. before returning to the bromination reactor as described above.

Hydrogen generated in the electrolyzer is discharged via line 256, compressed in a compressor 257, and possibly sent to energy block 258. Residual methane or other inert gases can be removed from the methanol formation reactor via line 259. Methane or natural gas can be sent to the energy block 258 to increase energy production. If necessary, additional natural gas or methane can be supplied to this unit via line 260.

In the laboratory implementation of the process elements of FIG. 3, methane was reacted with gaseous bromine at 450 ° C in a bromination reactor in the form of a glass tube with a passage time of 60 s. The products are methyl bromide, HBg and dibromomethane with a methane conversion of 75%. In the methanol formation reactor, methyl bromide, HBr and dibromomethane react with water in the presence of sodium hydroxide to form methanol and formaldehyde (from dibromomethane). Further, it is shown that there is a disproportionation of formaldehyde to methanol and formic acid. Therefore, in general, the products are methanol and formic acid.

During the process of FIG. 3, membrane type electrolytic cells are used, not diaphragm type cells. In the membrane cell, sodium ions with only a small amount of water flow into the cathode chamber. On the contrary, in a diaphragm-type cell, sodium ions and water enter the cathode chamber. In an alternative embodiment of the invention shown in FIG. 4, diaphragm cells are used, which leads to continuous depletion of the anolyte according to No. 1Bg. To replenish the NaBh content, the depleted anolyte is taken along line 252 to a separation column 253, where the bromine is distilled off and transferred to a compressor 249, and then to a desiccant 250. The NaBa solution from the separation column 253 is transferred via line 270 to storage tank 238 No. Vg. where it is mixed with a richer No. 1Bg solution. Other process features are similar to those shown in FIG. 3.

In another aspect of the invention, molecular halogen is recovered by electrolysis using a non-hydrogen cathode, i.e. cathode with oxygen depolarization, which significantly reduces energy consumption by producing water instead of hydrogen. In FIG. 5 shows one embodiment of this aspect of the invention; in this case we are talking about obtaining higher hydrocarbons. The process diagram is similar to that shown in FIG. 1, with the differences described below.

Bromine and natural gas, methane or another light hydrocarbon are forced to react in the bromination reactor 303, and then in the condensation reactor 305. Organics and HBg are separated in block 307 of the absorption of HBg. The aqueous sodium bromide is transferred via line 315 to an electrolytic cell 316 equipped with an anode 317, an oxygen depolarization cathode 318, and an oxygen inlet pipe or line 324. Possibly, additional water or electrolyte, or chemicals, are added to line 319 into the cell to control the pH.

Molecular bromine is released at the anode (2W ^- ^ W2 + 2e ^- ), and wet bromine is transferred via line 320 to desiccant 321, through heater 323, and then sent back to bromination reactor 303. At the cathode, the electrolytic reduction of oxygen occurs in the presence of water (1 / 2O2 + _H2O + 2e ^- 2OH * ^-) and hydroxyl ions are discharged as aqueous sodium hydroxide through line 311 to block 307 HBr absorption.

The invention also provides an improved electrolytic cell for converting halides into molecular halogen, one embodiment of which is shown in FIG. 6. Cell 400 includes a gas distribution manifold 401 through which oxygen gas, air, or oxygen-enriched air can be introduced; a gas diffusion cathode 402 that is permeable to oxygen (or an oxygen-containing gas); cation exchange membrane 403; cathode electrolyte chamber 404 located between the cation exchange membrane and gas diffusion

- 9 017229 cathode; the anode electrolyte chamber 405 and the anode 406 extending into the anode electrolyte chamber. When operating in an alkaline (basic) environment, water is introduced into the cathode electrolyte chamber through opening 407, and aqueous sodium hydroxide is removed from this chamber through another opening 408. Similarly, aqueous sodium bromide is introduced into the anode electrolyte chamber through opening 409, and molecular bromine is removed from the anode electrolyte chamber via line 410. The anode and cathode can be connected to a power source (not shown), which may include equipment for converting alternating current to direct current (for example, mechanical (electrical contact) rectifier, generator-motor unit, semiconductor rectifier, synchronous converter, etc.) and other components.

During operation, water is introduced into the cathode electrolyte chamber through a water inlet 407, and aqueous sodium bromide is introduced into the anode electrolyte chamber 405 through a hole 409. An oxygen stream is supplied through the gas distribution manifold 401 and the cell is powered. At the anode, sodium bromide is reduced, gaseous bromine liberated is diverted along line 410, and sodium ions are transferred through a cation exchange membrane to the cathode electrolyte chamber. At the cathode, electrolytic reduction of oxygen to a hydroxyl ion occurs in the presence of water. Aqueous sodium hydroxide leaves the cathode electrolyte chamber through opening 408.

The electrolytic cell described herein can be used in combination with various processes, including the embodiments described above. Its use is especially preferred where the reduction of energy consumption is important and hydrogen evolution is undesirable (for example, where special fire protection measures are required, for example, on offshore drilling rigs).

Although the invention can be applied in various industrial processes, it is of particular value where the continuous production process described here, for example, of higher hydrocarbons or methanol, is carried out on an offshore oil drilling rig, or on a drilling platform, or on an object located on shore in a remote place. Part of the usefulness of the invention is the conversion of a difficult-to-transport material (e.g., natural gas) to a more easily transportable liquid material, such as higher hydrocarbons or methanol. In addition, the usefulness of the invention lies in the use of electric generating capacities existing at the production facility, such as an electric generator or other power supply source.

According to one embodiment of this aspect of the invention, there is provided an improved production facility in which oil or gas is pumped out of a well and thereby extracted from the earth, wherein said facility has an electric generator or other power supply, the improvement including:

(a) the formation of alkyl halides in the reaction of molecular halogen with oil or gas pumped out of the well, under process conditions sufficient to form alkyl halides and hydrogen halide, optionally with almost complete consumption of molecular halogen;

(b) the formation of higher hydrocarbons and hydrogen halide by contacting the alkyl halides with the first catalyst under process conditions sufficient to form higher hydrocarbons and hydrogen halide;

(c) separating higher hydrocarbons from hydrogen halide;

(b) the electrolytic conversion of hydrogen halide to hydrogen and molecular halogen using electrical energy provided by an electric generator or power source, whereby the halogen can be reused.

In another embodiment, an improved production facility is proposed in which oil or gas is pumped out of the well and thereby extracted from the earth, wherein said facility has an electric generator or other source of power supply, the improvement including:

(a) the formation of alkyl halides in the reaction of molecular halogen with a hydrocarbon feed under process conditions sufficient to form alkyl halides and hydrogen halide, optionally with almost complete consumption of molecular halogen;

(b) the formation of methanol and an alkali metal halide by contacting the alkyl halides with aqueous alkali under process conditions sufficient to form methanol and an alkali metal halide;

(c) separating methanol from an alkali metal halide;

(b) the electrolytic conversion of hydrogen halide to hydrogen, molecular halogen and aqueous alkali using electrical energy provided by an electric generator or power source, whereby the halogen and alkali can be reused.

In another aspect of the invention, the general approach outlined above, including the steps of halogenation, product formation, product separation and electrolytic halogen regeneration, is used to produce alkyl amines. Thus, in one embodiment, natural gas, methane, or another aliphatic hydrocarbon feed is converted to alkyl amines via intermediate alkyl bromides.

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The feed and gaseous bromine are transferred through separate lines to the bromination reactor and allowed to react. Bromination products (e.g. methyl bromide and HBg) and possibly unreacted hydrocarbons are transferred through another line through a heat exchanger that lowers their temperature. The alkyl bromides are then transferred through another line to the amination reactor. Ammonia or aqueous ammonia is fed to the amination reactor in a separate line. Alkyl bromide and ammonia are allowed to react under process conditions sufficient to form alkyl amines (eg, ΚΝ ₂ ) and sodium bromide, which are then separated in a manner analogous to that described above for methanol production. Aqueous sodium bromide is transferred along another line to the electrolytic cell or cells, where it is electrolytically converted to hydrogen and molecular bromine, which allows reuse of bromine in the next cycle.

In FIG. 7 and 8 show two other aspects of the invention in which coal is converted to more valuable coke or coal or biomass is converted to more valuable polyols (polyalcohols) and the halogen used in the process is regenerated electrolytically. In the embodiments shown in FIG. 7, crushed coal is allowed to react with molecular bromine at an elevated temperature to form coke, HBr and armored intermediates of coal processing (C _x Br _p ). The brominated coal processing intermediates are converted to coke, allowing them to come in contact with the catalyst, and additional hydrogen bromide is formed. Then, coke and hydrogen bromide are separated, then hydrogen bromide is transferred along another line to an electrolytic cell or cells similar to those described above, whereby molecular bromine can be regenerated and reused.

In FIG. Figure 8 shows a similar process in which coal or biomass-derived hydrocarbons are brominated, whereby alkyl bromines or alkyl bromides and HBg are formed, which are then treated in a manner similar to that described above, for example, alkyl bromides and HBg are at least partially separated, and the alkyl bromides are allowed to react with alkali (for example, sodium hydroxide), resulting in the formation of sodium bromide, water and polyalcohols (C _X N _Y-H (OH) _H ). The polyalcohols are separated from sodium bromide and the aqueous sodium bromide is transferred in yet another line to the electrolytic cell or cells where molecular bromine is regenerated and subsequently separated and reused.

The following non-limiting examples illustrate various embodiments or features of the invention, including bromination of methane; CC condensation with the formation of higher hydrocarbons, for example light olefins and aromatic compounds (benzene, toluene, xylenes (BTX)); hydrolysis of methyl bromide in methanol; hydrolysis of dibromomethane to methanol and formaldehyde, followed by disproportionation to formic acid.

Example 1. Bromination of methane.

Methane (11 stcm ³ / min, 1.0 atm) was mixed with nitrogen (15 stcm ³ / min, 1.0 atm) at room temperature in a T-shaped mixer and passed through a barbator filled with bromine at 18 ° FROM. A mixture of CH ₄ A ₂ / Br _{2 was} passed into a preheated glass tube (inner diameter 2.29 cm, length 30.48 cm filled with glass granules) at 500 ° C, where methane was brominated with a residence time of 60 s, to obtain the main bromomethane, dibromomethane and HBg

CH, + Br ₂ CH ₃ Br + CH ₂ Br ₂ + HBg.

As the products exit the reactor, they were collected using a series of traps containing | M No. YOUNG. neutralizing HBr, and hexadecane (containing octadecane as an internal standard) to dissolve as many hydrocarbon products as possible. Volatile components, such as methane, were collected in a gas bag after HBr / hydrocarbon traps.

After the completion of the bromination reaction, coke or carbon deposits were burnt in a stream of heated air (5 stcm ³ / min) at 500 ° С for 4 h and CO _{2 was} captured with a saturated solution of barium hydroxide in the form of barium carbonate. Quantitative analysis of all products was carried out by gas chromatography (GC). The amount of coke was determined by the amount of CO ₂ released during coke removal. The results are shown in FIG. nine.

Example 2. Condensation of CH ₃ Vg to light olefins.

2.27 g of magnesium doped with Mg (MD) for 5% zeolite Ζ8Μ-5 (SVU8014) was loaded into a tubular quartz reactor (internal diameter 1.0 cm), which was previously heated to 400 ° С before the start of the reaction. CH ₃ Vg diluted with Ν ₂ was pumped into the reactor at a flow rate of 24 μl / min for CH ₃ Vg controlled by a liquid micropump and 93.3 ml / min for Ν ₂ . At these established costs, the condensation reaction of CH ₃ Vg occurred over the catalyst bed with a residence time of 0.5 s and a partial pressure of CH ₃ Vg of 0.1.

After 1 h of reaction, the products left the reactor and were collected using a series of traps containing 4 M NO, neutralizing HBr, and hexadecane (containing octadecane as an internal standard) to dissolve as many hydrocarbon products as possible. Volatile components, such as methane and light olefins, were collected in a gas bag after HBr / hydrocarbon traps.

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After the completion of the condensation reaction, coke or carbon deposits were burnt in a stream of heated air (5 stcm ³ / min) at 500 ° С for 4 h, and CO _{2 was} captured with a saturated solution of barium hydroxide in the form of barium carbonate. Quantitative analysis of all products was carried out by GC. The amount of coke was determined by the amount of CO ₂ released during coke removal. The results are shown in FIG. 10.

Even with such a short residence time, the conversion of CH ₃ Br reached 97.7%. Among the condensation products, the main products are C ₃ H ₆ and C ₂ H ₄ ; their sum made a 50% contribution to the carbon yield. BTX (benzene, toluene, xylenes), other hydrocarbons, brominated hydrocarbons and a small amount of coke made up the remainder of the converted carbon.

Example 3. Condensation of CH ₃ Vg to BTX.

The Μη-ion-exchange zeolite Ζ8Μ-5 granules (SVU3024, 6 cm long) were loaded into a tubular quartz reactor (inner diameter 1.0 cm), preheated to 425 ° С before the start of the reaction. CH ₃ Vg diluted with Ν ₂ was pumped into the reactor at a flow rate of 18 μl / min for CH ₃ Vg, controlled by a liquid micropump, and 7.8 ml / min for Ν ₂ . At these established costs, the condensation reaction of CH ₃ Vg occurred over the catalyst bed with a residence time of 5.0 s and a partial pressure of CH ₃ Vg of 0.5.

After 1 h of reaction, the products left the reactor and were collected using a series of traps containing 4 M No. 1OH. neutralizing HBr, and hexadecane (containing octadecane as an internal standard) to dissolve as many hydrocarbon products as possible. Volatile components, such as methane and light olefins, were collected in a gas bag after HBr / hydrocarbon traps.

After the completion of the condensation reaction, coke or carbon deposits were burnt in a stream of heated air (5 stcm ³ / min) at 500 ° С for 4 h, and CO _{2 was} captured with a saturated solution of barium hydroxide in the form of barium carbonate. Quantitative analysis of all products was carried out by GC. The amount of coke was determined by the amount of CO2 released during coke removal. The results are shown in FIG. 8.

In this operating mode, for maximum VTX output, CH ₃ Vg can be completely converted. The BTX yield reached 35.9%. The contribution of other hydrocarbons, aromatic compounds, brominated hydrocarbons and coke to the carbon yield was 51.4, 4.8, 1.0 and 6.9%, respectively. The main component of other hydrocarbons is propane, and it can be returned to the system for reproportionation, followed by further condensation to further increase the overall yield of BTX.

Example 4. Alkaline hydrolysis of bromomethane to methanol

СЩВг + ИАОН СН ₃ ОН + ИАВ

13.2 g of a 1 M aqueous solution of sodium hydroxide (13.2 mmol) and 1.3 g of bromomethane (12.6 mmol) were successively introduced into a 30 ml stainless steel reactor with a localization of vapor of 30 ml capacity equipped with a magnetic stirrer. The reactor was carefully purged with nitrogen to remove air from the top of the reactor before closing the lid. The closed reactor was placed in an aluminum heating block, preheated to 150 ° C, to immediately begin the reaction. The reaction was carried out for 2 hours at a given temperature with stirring.

After termination of the reaction, the reactor was placed in an ice bath at the initial moment to cool the products inside. After opening the reactor, the reaction liquid was transferred to a vessel and diluted with cold water. The vessel was connected to a gas bag used to collect unreacted bromomethane, if any. The reaction liquid was weighed and the concentration of the products was analyzed by gas chromatography with PID (flame ionization detector) on a capillary column adapted for introducing an aqueous sample.

Analysis of the gaseous product shows that there was no residual bromomethane, indicating that the bromomethane was completely converted. Based on measurements of concentrations in the liquid product, the calculated methanol yield, including trace amounts of dimethyl ether, was 96%.

Example 5. Alkaline hydrolysis of dibromomethane to formaldehyde followed by disproportionation to methanol and formic acid

CH ₂ Vg ₂ + 2KaON - "HCNO + 2KaVg + H ₂ O

HCNO + 1 / 2H ₂ OH -> 1 / 2CH ₃ OH + 1 / 2NSSYUN

The alkaline hydrolysis of dibromomethane was carried out according to the same procedure as in Example 5, with the difference that a high ratio of No. 1OH / CH ₂ Br ₂ (2.26) was used. After collecting the reaction liquid, a sufficient amount of a concentrated solution of hydrogen chloride was added to neutralize the excess sodium hydroxide and acidify the sodium formate. It was noted that methanol and formic acid were the only products, indicating that, following hydrolysis to methanol and formaldehyde, there was a complete disproportionation of formaldehyde to (additional) methanol and formic acid. GC analysis showed that the conversion of dibromomethane reached 99.9%; at the same time, the yields of methanol and formic acid reached 48.5 and 47.4%, respectively.

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Examples 4 and 5 demonstrate that complete hydrolysis of bromomethane to methanol is possible, as well as complete hydrolysis of dibromomethane to methanol and formic acid under slightly alkaline conditions. The results are presented in the table.

Alkaline hydrolysis of CH ₃ Vg and CH ₂ Vg ₂ followed by disproportionation of HCNO

Source form SNzVg CH.Vg, IAOH / CHzVg or CH ₂ Br ₂ 1.05 2.17 Temperature (° C) 150 150 Reaction Time (s) 2 2 Conversion (%) 100.0 99.9 The output of SNzon (%) 96.0 48.5 UNSO yield (%) 47.4

The invention has been described with reference to various representative and preferred embodiments, but is not limited to. Other modifications and equivalent arrangements apparent to those skilled in the art upon consideration of this disclosure are also included within the scope of the invention.

As one example, molecular bromine can also be removed from the electrolytic cell (s) using a competitive extraction method using an inert organic solvent such as chloroform, carbon tetrachloride, ether, and the like. The solvent is introduced on one side of the cell; there is a distribution of bromine between the organic and aqueous phases; the bromine-laden solvent is removed from the other side of the cell. The bromine can then be separated from the solvent by distillation or another suitable method, and then returned to the system for reuse. The distribution is facilitated by the significantly greater solubility of bromine in solvents such as chloroform and carbon tetrachloride, compared with solubility in water. Extraction by this method serves a dual purpose: it separates Br ₂ from other forms of bromine that may be present (for example, Br ^- , Br ^- which are insoluble in the organic phase); and it allows you to concentrate bromine and easily separate it from the organic phase (for example, by distillation). The optimum pH during extraction (as well as for the separation of bromine by heating bromine-containing aqueous solutions in the gas stream) is 3.5 - the pH at which the concentration of molecular bromine (Br ₂ ) is maximum in comparison with other forms of bromine.

As another example of modifications of the method described in the present invention, various pumps, taps (valves), heaters, coolers, heat exchangers, control units, power supplies and other equipment can be used to optimize processes in addition to or alternatively to those shown in the figures. Additionally, in the practical implementation of the present invention, the use of other features and implementation options, such as described in the application 358 or elsewhere. The invention is limited only by the appended claims and their equivalents.

Claims (13)

CLAIM 1. A continuous method for the conversion of hydrocarbons to higher hydrocarbons, including: (a) reacting molecular halogen with a hydrocarbon feed to form alkyl halides and hydrogen halide; (b) contacting the alkyl halides with a catalyst to form higher hydrocarbons and hydrogen halide; (c) separating higher hydrocarbons from hydrogen halide; (b) electrolytic conversion of hydrogen halide to hydrogen and molecular halogen; (e) repeating steps (a) to (b) the desired number of times, wherein the molecular halogen from step (b) is used in the repeated step (a). 2. The continuous method according to claim 1, wherein the hydrocarbon feed contains natural gas. 3. The continuous method according to claim 1, wherein the hydrocarbon feed contains methane. 4. The continuous method according to claim 1, wherein step (b) is carried out in an aqueous medium. 5. The continuous method according to claim 1, wherein step (b) is carried out in the gas phase. 6. The continuous method according to claim 1, wherein the higher hydrocarbons contain fuel hydrocarbons and / or aromatic hydrocarbons. 7. The continuous method according to claim 6, wherein the aromatic hydrocarbons contain benzene, toluene and xylenes. 8. The continuous method according to claim 1, wherein step (b) comprises the electrolytic conversion of hydrogen halide to hydrogen and molecular halogen using an electrolytic cell including - 13 017229 gas distribution manifold, through which oxygen gas, air or oxygen-enriched air can be introduced; a gas diffusion cathode that is permeable to oxygen or an oxygen-containing gas; cation exchange membrane; a cathode electrolyte chamber located between the cation exchange membrane and the gas diffusion cathode; an anode electrolyte chamber; and an anode extending into the anode electrolyte chamber. 9. The continuous method according to claim 1, wherein the hydrocarbon feedstock contains oil or gas pumped from a well at an oil or gas production facility, wherein the hydrogen halide is converted to hydrogen and molecular halogen using electrical energy provided by an electric generator or electric power source. 10. The continuous method according to claim 9, wherein the oil and gas production facility is located offshore. 11. The continuous method according to claim 9, wherein step (b) comprises the electrolytic conversion of hydrogen halide to hydrogen and molecular halogen using electrical energy provided by an electric generator or power source, using an electrolytic cell including a gas distribution manifold through which it is possible to introduce gaseous oxygen, air or oxygen enriched air; a gas diffusion cathode that is permeable to oxygen or an oxygen-containing gas; cation exchange membrane; a cathode electrolyte chamber located between the cation exchange membrane and the gas diffusion cathode; an anode electrolyte chamber; and an anode extending into the anode electrolyte chamber. 12. The continuous method according to claim 1, wherein step (b) comprises the electrolytic conversion of hydrogen halide to water and molecular halogen in an electrolytic cell or cells equipped with an oxygen depolarization cathode. 13. The continuous method according to claim 12, wherein the electrolytic cell comprises a gas distribution manifold through which oxygen gas, air or oxygen enriched air can be introduced; a gas diffusion cathode that is permeable to oxygen or an oxygen-containing gas; cation exchange membrane; a cathode electrolyte chamber located between the cation exchange membrane and the gas diffusion cathode; an anode electrolyte chamber; and an anode extending into the anode electrolyte chamber.