Method of propylene production by recycling of heavy fractions

FIELD: manufacturing technology.

SUBSTANCE: invention relates to two versions of method of propylene production. One of versions includes: metathesis reaction of raw supply stream consisting of mixture of n-butene with ethylene in presence of metathesis catalyst to form fraction containing propylene, ethylene, butene and C5+ olefins, 2-pentene and 3-hexene; extraction of propylene from ethylene, butene and C5+ olefins from fraction of metathesis products; and recirculation of at least part of C5+ olefins for metathesis reaction recycled C5+ olefins are converted into propylene and butene, wherein ethylene is introduced into metathesis reaction at ratio, which is sufficient for maintaining reaction, where C4+ ratio for reaction with metathesis catalyst ranges from 0.3:1 to 3:1 and at least 5 % of C5+ olefins return into metathesis reaction.

EFFECT: use of recycling of C5+ olefin gasoline increases efficiency of method with low total flow through metathesis reactor.

11 cl, 3 dwg

 



 

Same patents:

FIELD: chemistry.

SUBSTANCE: present invention relates to a method of preparing a catalyst complex of formula , where R1, R2, R3 and R4 are independently selected from a group consisting of hydrogen, C1-C20alkyl, C2-C20alkoxy group, halogen and amino group, where if R1 or R3 is an amino group, the amino group is optionally substituted with one or more fragments which are alkyl, if R2 or R4 is an amino group, the amino group is optionally substituted with one or more fragments which are C1-C20alkyl. The method includes a step of reacting a ruthenium catalyst precursor with one or two bidentate ligands of the Schiff base class in a nonpolar solvent and in the presence of a weak base, where the bidentate ligands of the Schiff base class are independently in amount of 1.0-3.0 equivalents relative to the amount of the catalyst precursor (formulae of the precursors and ligands are given in claim 1 of the invention). The invention also discloses a catalyst complex, a supported catalyst for metathesis of olefins and use thereof in olefin metathesis reactions.

EFFECT: invention enables to obtain a catalyst having high activity after activation, monomer stability and a simple and cheap method.

11 cl, 2 tbl

FIELD: chemistry.

SUBSTANCE: invention relates to a method of converting a stream of C4 olefins containing isobutene, but-1-ene and butadiene to propylene and octenes. The method involves a) selective hydrogenation of the stream of C4 olefins in the presence of a catalyst to remove butadiene via partial hydrogenation to butenes, and converting but-1-ene to but-2-ene to obtain a partially hydrogenated effluent; b) separating the partially hydrogenated effluent through distillation into a head fraction containing but-1-ene and hydrocarbon compounds which boil at a lower temperature than but-1-ene, and a bottom fraction containing compounds which boil at a higher temperature than but-1-ene; c) feeding at least a portion of the head fraction from step (b) as dimerisation material into a dimerisation reactor, wherein the dimerisation material undergoes dimerisation in the presence of a dimerisation catalyst to form a dimerisation reaction product; d) separating at least a portion of the dimerisation reaction product to form a liquid stream rich in octene and a vapour stream rich in C4; e) feeding the octene-rich liquid stream from step (d) to distillation step (b) and removing the bottom product from the distillation step (b) which contains almost all octene from the liquid stream rich in octene; f) removing a middle fraction product containing but-2-ene from the distillation step (b) from an intermediate point between points where the head and bottom fractions are extracted; and g) the middle fraction product undergoes metathesis with ethylene in the presence of a metathesis catalyst to obtain a metathesis reaction product containing propylene. The invention also relates to an apparatus realising said method.

EFFECT: use of the present invention reduces capital and operating costs and improves characteristics of the metathesis material.

10 cl, 1 dwg

FIELD: chemistry.

SUBSTANCE: invention relates to oil and gas chemistry and specifically to catalysts and processes for synthesis of light alkenes, particularly propylene. Described is a catalyst for single-step synthesis of propylene from ethylene, containing rhenium oxide Re2O7 and nickel oxide NiO, attached to the surface of a carrier in form of borate-containing aluminium oxide with the following ratio of components in wt %: Re2O7 - 5-13; NiO - 4-8; B2O3 - 15-18; Al2O3 - the rest. Described is a method of preparing said catalyst, which involves preliminary production of borate-containing aluminium oxide by mixing a hydrate of aluminium oxide having a pseudo-boehmite structure with ortho-boric acid, drying at 120°C and calcination at 550°C in an air current for 16 hours, followed by saturation of the borate-containing aluminium oxide with an aqueous solution containing perrhenic acid and nickel nitrate, drying at 120°C and calcination at 550°C for 16 hours. Described also is a method for single-step synthesis of propylene from ethylene which involves passing a stream of pure (100%) ethylene through a fixed layer of the disclosed catalyst at temperature 40-150°C, pressure close to atmospheric pressure and mass flow rate of feeding ethylene equal to 1 h-1.

EFFECT: high efficiency of single-step synthesis of propylene from ethylene owing to high selectivity of formation and output of propylene.

3 cl, 1 tbl, 7 ex

FIELD: chemistry.

SUBSTANCE: method of producing olefins via a metathesis reaction, involving supply of gaseous olefin for passage through a catalyst bed in the presence of hydrogen gas, for converting olefin to another type of olefin, the catalyst bed containing a catalyst which contains at least one metal selected from a group comprising tungsten, molybdenum, rhenium, niobium, tantalum and vanadium, and a cocatalyst which contains a basic composition containing at least one metal selected from groups Ia (alkali metals), IIa (alkali-earth metals), IIb and IIIa of the periodic table. The improvement lies in controlling the reduced velocity of gas passing through the catalyst bed which ranges from 0.01 to 2.0 m/s, wherein the reaction pressure ranges from 0.01 to 20 MPa and the amount of the cocatalyst relative the catalyst ranges from 0.1 to 20 of the weight.

EFFECT: use of the method increases efficiency of the metathesis reaction for producing olefins in the presence of hydrogen along with suppression of secondary production of paraffins.

3 cl, 4 ex, 1 dwg

FIELD: explosives.

SUBSTANCE: one of methods includes the following stages: a. steam-phase cracking of ethane or mainly ethane initial raw materials, containing 70% or more of ethane, with production of, thereby, cracking product, containing ethylene, hydrogen, ethane, methane, acetylene and C3 and heavier carbohydrates; b. processing of mentioned cracking product in extraction section of ethylene plant, also removal of mentioned hydrogen, methane and C3 and heavier carbohydrates from it and conversion of mentioned acetylene available in it mainly into ethylene with production of, thereby, cracking product exposed to processing, containing mainly ethylene and ethane, and also fractioning of specified cracking product that has been processed into C2 fractioning column and production of ethylene fraction, consisting of chemical ethylene and characterized with level of ethylene content below 99% (vol.), and ethane fraction in the form of distillation residue; c. sending of specified ethane fraction in the form of distillation fraction for recycle to specified steam-phase cracking; d. performance of reaction by mechanism of dimerisation in dimerisation section for the first part of specified ethylene fraction with thereby production of butene-enriched flow; e. performance of reaction by metathesis mechanism in metathesis section between butene in specified flow enriched with butene, and the second part of specified ethylene fraction with thereby production of flow enriched with propylene, ethylene and ethane; f. separation of propylene from specified ethylene and ethane in specified flow enriched with propylene and g. sending of at least part of specified ethylene and ethane from specified flow enriched with propylene for recycle into mentioned C2 fractioning plant. Besides invention is related to method for production of propylene from carbohydrate raw materials.

EFFECT: application of proposed methods makes it possible to improve and make process of propylene production from carbohydrate initial raw materials more profitable.

39 cl, 6 dwg

FIELD: chemistry.

SUBSTANCE: invention relates to a method of converting a C4 stream, containing 1-butene and 2-butene, preferably into 2-butene, involving: mixture of the said C4 stream with the first hydrogen stream to form the input stream, hydroisomerisation of the said input stream in the presence of first hydroisomerisation catalyst, so as to convert at least part of the said 1-butene to 2-butene and obtain an output hydroisomerisation product, separation of the output hydroisomerisation product in a catalytic distillation column, with a top end and a bottom end, to obtain a mixture of 1-butene at the said top end, a top output stream which contains isobutene and isobutylene, and a bottom stream which contains 2-butene, and hydroisomerisation of the said mixture of 1-butene at the said top end of the catalytic distillation column using a second hydroisomerisation catalyst to obtain additional 2-butene in the said bottom stream; where location of the said second hydroisomerisation catalyst in the top section of the column as a separate reaction zone is chosen to achieve maximum concentration of 1-butene, under the condition that, the hydroisomerisation stage with participation of the second isomerisation catalyst does not take place. The invention also relates to an apparatus for realsing this method and a method of producing propylene from a C4 stream.

EFFECT: selective hydrogenation of 1-butene to 2-butene which is more efficient than existing technologies.

30 cl, 7 dwg, 4 tbl, 2 ex

FIELD: chemistry.

SUBSTANCE: method of olefins preparation by metathesis reaction includes the interreaction of homological or heterological olefines with formation of olefins having other structure whereat the reaction is carried out in compresence of gaseous hydrogen and catalyst containing at least one element - metal selected from tungsten and molybdenum and having the structure of catalyst applied to carrier - silicon dioxide and in presence (in addition to catalyst) of the compound containing at least one element -metal selected from metals of the group Ia (alkali metals), group IIa (alkali-earth metals), group IIb and group IIIa as cocatalyst with cocatalyst/catalyst mass ratio being in the range from 0.1 to 20 wt. The amount of gaseous hydrogen taken in compresence with starting materials loaded to reactor is 0.1-80% by volume of total gas amount (taking into account the gaseous state of starting materials).

EFFECT: method of olefines preparation possesses the significant safety, operation and economic advantages.

10 cl, 16 tbl, 14 ex

FIELD: chemistry.

SUBSTANCE: raw material composition based on fatty acids or esters of fatty acids, obtained by hydrolysis of oil from seeds or by re-etherification of oil from seeds with C1-8-alkanol, contains more than 70 wt % of unsaturated fatty oleic acid, and less than 1.5 milliequivalents of admixture(s), poisoning methathesis catalyst, per kilogram of composition, after purification with adsorbent. Admixture contains one or more organic hydroperoxides. Method of olefin methathesis lies in contacting of raw composition, obtained from seed oil and containing one or more unsaturated fatty acids or esters of unsaturated fatty acids, with lower olefin in presence of catalyst based on phosphororganic transition metal complex. Used raw material composition contains less than 25 milliequivalents of admixture(s), poisoning methathesis catalyst, per kilogram of raw material composition, able to inhibit methathesis catalyst. As a result of reaction olefin with shortened chain and unsaturated acid or unsaturated ester with shortened chain is obtained. Method of obtaining complex polyether polyepoxide lies in carrying out the following stages. At the first stage raw material compositiojn, obtained from seed oil, containing one or more unsaturated fatty acids or esters of fatty acids, contacts with lower olefin in presence of olefin methathesis catalyst. Used raw material composition contains less than 25 milliequivalents of admixture(s), poisoning methathesis catalyst, per kilogram of composition. At the second stage (re)etherification of obtained unsaturated acid with shortened chain or unsaturated ester with shortened chain with polyol is carried out. At the third stage epoxidation of obtained complex polyether polyolefin is carried out with epoxidising agent optionally in presence of catalyst. Method of obtaining α,ω-oxoacid, complex α,ω-oxyester and/or α,ω-diol with shortened chain lies in carrying out the following stages. At the first stage raw material composition, obtained from seed oil, containing one or more unsaturated fatty acids or esters of fatty acids contacts with lower olefin in presence of olefin methathesis catalyst. Used raw material composition contains less than 25 milliequivalents of admixture(s), poisoning methathesis catalyst, per kilogram of composition. At the second stage hydroformilation is carried out with hydrating of obtained unsaturated acid or ester with shortened chain in presence of hydroformiolation/hydration catalyst.

EFFECT: increase of catalyst serviceability and obtaining chemical compounds with high productivity.

25 cl, 3 tbl, 12 ex

FIELD: petrochemical processes and catalysts.

SUBSTANCE: invention provides rhenium oxide catalyst on anion-containing gamma-alumina-based support: 0.1-10.0% Re2O3 and 0.2-4.0% fluorine based on the weight of alumina. Catalyst is prepared by impregnating alumina, including 0.2-4.0 wt % fluorine, with rhenium compound solution, drying resulting mass, and subjecting it to heat treatment in oxidative and/or inert medium at 600-900°C. Propylene synthesis process including metathesis of C2-C4-olefinic hydrocarbon blend or ethylene alone is also described.

EFFECT: increased catalytic activity and simplified technology.

7 cl, 2 tbl, 8 ex

FIELD: petrochemical processes and catalysts.

SUBSTANCE: invention relates to supported olefin metathesis catalyst and to a olefin metathesis process using the latter. Catalyst is essentially composed of transition metal or oxide thereof, or a mixture of such metals, or oxides thereof deposited on high-purity silicon dioxide containing less than: 150 ppm magnesium, 900 ppm calcium, 900 ppm sodium, 200 ppm aluminum, and 40 ppm iron. When pure 1-butene comes into interaction with this catalyst under metathesis reaction conditions, reaction proceeds with 2-hexene formation selectivity at least 55 wt %. Use of catalyst according to invention in olefin metathesis process minimizes double bond isomerization reactions.

EFFECT: increased olefin metathesis selectivity regarding specific products.

17 cl, 2 tbl, 2 ex

FIELD: chemistry.

SUBSTANCE: invention relates to method of obtaining olefin, which includes the following stages: supply of flow of raw material, which contains paraffin hydrocarbon, into distillation section; supply of flow, discharged from distillation section, into reactor and interaction of flow, discharged from distillation section, in reactor with formation of olefin-containing flow, discharged from reactor; supply of raw material flow of distillation column, which communicated with and is downstream flow, discharged from reactor, into olefin distillation column; supply of flow, discharged from distillation column, into heat pump compressor; and supply of flow, discharged from heat pump compressor, into distillation section and application of heat from flow, discharged from heat pump compressor, for heating flow of distillation section, which contains paraffin hydrocarbon that has not reacted.

EFFECT: heat saving.

10 cl, 5 dwg

FIELD: chemistry.

SUBSTANCE: invention relates to method of dehydration of alkanes with balancing product composition. Gaseous flow of substance, which contains alkanes, is passed in continuous mode through catalyst layer, located in from two to 10 successfully connected reactors of adiabatic, allothermic or isothermic type or in their combination, which results in formation of gaseous flow, containing olefin, hydrogen and alkane which has not reacted, with at least one reactor being adiabatic one, which oxygen is supplied to. At least one of the process parameters: temperature, pressure or ratio of vapour and hydrocarbons is registered in one or more points on at least one of reactors in form of measured values, at least one of the process parameters is purposefully controlled and subjected to impact so that composition of produced gas at output of at least one of reactors remains constant during operation time. Invention also relates to application of said method for dehydration of particular hydrocarbons.

EFFECT: application of claimed method makes it possible to obtain product with constant composition at the output from reactor during the entire operation time.

15 cl, 1 tbl, 5 ex, 8 dwg

FIELD: chemistry.

SUBSTANCE: invention relates to the application of a catalyst, which contains a monolith and a layer of the catalyst, for the dehydrogenation of alkanes to alkenes or aromatisation in dehydrogenation. The monolith consists of a catalytically inert material with BET surface area <10 m2/g, with the catalyst layer, applied on the monolith, containing platinum and tin and/or rhenium and if necessary other metals on an oxide carrier material, the catalyst layer thickness constitutes from 5 to 500 microns. In addition, the hour volume rate of gas supply constitutes from 500 to 2000 h-1. The invention also relates to methods of the dehydrogenation of alkanes to alkenes and aromatisation in dehydrogenation with the application of the catalyst described above.

EFFECT: claimed application of the catalyst provides high conversions, volume productivity and selectivity.

14 cl, 13 tbl, 25 ex

FIELD: chemistry.

SUBSTANCE: invention refers to a method for producing propylene by catalytic oxidative dehydration of propane involving passing a reaction mixture flow containing propane and an oxidative agent in the inert gas medium used as a thinner through a catalyst layer in a flow reactor. The oxidative agent is elemental chlorine.

EFFECT: method enables the high-selective production of propylene at a lower temperature.

7 cl, 5 ex

FIELD: chemistry.

SUBSTANCE: invention relates to method of obtaining light olefins. Method includes: (a) passing oxygenate raw material into reactor for converting oxygenates into olefins for oxygenate raw material to contact with molecular-sieve catalyst and to be converted in light olefins, which are discharged from reactor for conversion of oxygenates in olefins in form of outflow; (b) division of outflow into first flow of light olefins, separated from first flow, containing C4 and heavier hydrocarbons; (c) selective hydration and further cracking of first flow, containing C4 and heavier hydrocarbons, in second reactor of olefin cracking, with application of catalyst of olefin cracking, with formation of first outflow of cracking gases, containing light olefins; (d) separate cracking of hydrocarbon flow with formation of second outflow of cracking gases, containing light olefins, and separate flow of pyrolysis gas, containing C4 and heavier hydrocarbons; (e) co-fractionation of first and second outflows of cracking gases to obtain second flow, containing light olefins, separated from second flow, containing C4 and heavier hydrocarbons; (f) co-conditioning of first flow and second flow, containing light olefins to remove acidic gases and obtain conditioned flow; and (g) division of conditioned flow in flow of ethylene product, flow of propylene product and flow, containing C4 hydrocarbons.

EFFECT: method represents improvement of method of obtaining light olefins, achieved by reasonable combination of installation for conversion of oxygenates in olefins ("МВОЛ") with installation for pyrolysis of hydrocarbons.

10 cl, 2 dwg

FIELD: chemistry.

SUBSTANCE: invention relates to a method of producing light olefins, which comprises: (a) passing oxygen-containing feedstock into a reactor for converting oxygen-containing compounds to olefins, such that the oxygen-containing feedstock comes into contact with a molecular sieve-based catalyst and is converted to light olefins, which come out of said reactor in the form of an effluent stream; (b) dividing the effluent stream into a first stream of light olefins and a first stream containing C4 or heavier hydrocarbons separate from the first stream; (c) selective hydrogenation and subsequent cracking of the first stream containing C4 or heavier hydrocarbons to obtain a first effluent stream of cracking gases containing light olefins; (d) separate cracking of the hydrocarbon stream to obtain a second effluent stream of cracking gases containing light olefins; (e) combined fractionation of he first and second effluent streams of cracking gases to obtain a second stream containing light olefins, separate from the second stream containing C4 or heavier hydrocarbons; (f) combined treatment of the first and second streams containing light olefins to remove acidic gases and obtain a treated stream; (g) dividing the treated stream into an ethylene product stream, a propylene product stream and a stream containing C4 hydrocarbons; and (h) optional selective hydrogenation of the stream containing C4 hydrocarbons, and subsequent fraction of the optionally selectively hydrogenated stream to separate a 2-butene stream from the first 1-butene stream. The invention also relates to a method of extracting 1-butene from a stream of C4 hydrocarbons, which uses the method described above.

EFFECT: method is an improved process of obtaining light olefins through smart combination of an apparatus for converting oxygen-containing compounds to olefin with a hydrocarbon pyrolysis apparatus.

17 cl, 4 dwg

FIELD: chemistry.

SUBSTANCE: invention relates to a method of propane dehydrogenation, which includes passing of a preliminarily heated initial propane flow into a dehydrogenation reactor, mixing and interaction of the initial propane flow with a non-metallic fluidised catalyst, which contains zirconium oxide, in the dehydrogenation reactor, which represents a reactor of fast fluidisation with formation of a flow of a propylene-containing product. The catalyst is in the reactor with the average time of presence from 15 to 45 minutes; passing of a waste catalyst into a catalyst regeneration unit with formation of a flow of a regenerated catalyst; and passing the flow of the regenerated catalyst into the dehydrogenation reactor.

EFFECT: application of the claimed method makes it possible to increase the passing capability of the system.

8 cl, 1 dwg

FIELD: chemistry.

SUBSTANCE: pyrolysis of methylene chloride is carried out on a catalyst with a carbonisation degree in the range of 2.6-5.2 wt %, which is obtained during 60-150 minutes of a reactor work, after which in order to support the obtained degree of carbonisation a catalyst is constantly discharged into a regenerator, excessive carbon is removed by burning with air at a temperature of 550°C. After that it is returned into the reactor, providing constant circulation of the carbonised catalyst from the reactor of pyrolysis into the regenerator and back.

EFFECT: application of the method makes it possible to increase selectivity of the process of obtaining lower olefins due to increase of the catalyst selectivity, applied in the process of methylene chloride pyrolysis.

2 ex, 2 tbl

FIELD: chemistry.

SUBSTANCE: invention relates to a method of catalytic methane oxychlorination in a deck-type adiabatic reactor under pressure of 1-10 atm in presence of a catalyst, which contains on a porous carrier with a specific surface of 1-60 m2/g a mixture of copper, potassium and lanthanum chlorides in a molar ratio of 1:1:0.3 in an amount of 3-30 wt % of the carrier weight and distributed on each reactor deck by 30% higher than the previous one. The two-layered catalyst in the form of equal in volume layers is loaded into the deck-type adiabatic reactor by a flow of reaction gas on each deck of the adiabatic reactor, the first layer of the catalyst contains a mixture of copper, potassium and lanthanum chlorides in a molar ratio of 1:1:0.3, and the second layer of the catalyst - a mixture of copper and potassium chlorides in a molar ratio of 1:1.

EFFECT: conversion of hydrogen chloride remains stable when the claimed method is applied.

1 ex, 1 tbl

FIELD: chemistry.

SUBSTANCE: method is characterised by contacting a gas stream containing at least one of said hydrocarbons with a dehydrogenation catalyst containing gallium and platinum and deposited on a support made of aluminium oxide or aluminium oxide and silicon dioxide, at reaction temperature in a direct-flow, upward stream with weight ratio of catalyst to hydrocarbon of 5 to 100 in a dehydrogenation reactor, wherein the average contact time of the hydrocarbon with the catalyst in the zone of the dehydrogenation reactor ranges from 1 s to 4 s, and temperature and pressure in the dehydrogenation reactor range from 570 to 750°C and from 41.4 (6.0) to 308 (44.7) kPa (psia); and moving the hydrocarbon and the catalyst from the dehydrogenation reactor into a separation device, wherein the average contact time of the hydrocarbon with the catalyst at reaction temperature in the separation device is less than 5 s, and the full average contact time between the hydrocarbon, catalyst and the formed hydrocarbons is less than 10 s; and moving the catalyst from the separation device into a regenerator, where the catalyst is brought into contact with an oxygen-containing regenerating stream and additional fuel.

EFFECT: method has short contact time between the hydrocarbon and the catalyst.

7 cl, 5 dwg

FIELD: petrochemical processes.

SUBSTANCE: methanol vapors are converted on first catalyst into vapor mixture containing dimethyl ether and first vapor mixture is then converted on form-selective zeolite catalyst into propylene-containing product mixture. Form-selective zeolite catalyst is disposed in the form of charge in at least two in series connected shaft reactors. First portion of dimethyl ether-containing vapor mixture stream is passed to first shaft reactor, wherefrom first intermediate product is withdrawn and routed to second reactor, into which second portion of dimethyl ether-containing vapor mixture stream is supplied. From the last of in series connected reactors, product mixture is discharged and propylene-rich fraction is separated whereas residual materials thus obtained are partly in gaseous form. Al least a part of the latter are recycled into one of shaft reactors.

EFFECT: enhanced process efficiency and increased level of propylene in product mixture.

10 cl, 2 dwg, 1 tbl, 2 ex

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