The process of co-production of isoprene and 3-methylbutan-1

 

(57) Abstract:

Usage: in the petrochemical industry, in particular in the production of monomers for synthetic rubber - isoprene and 3-methylbutan-1. The essence of the invention: a process of co-production of isoprene and 3-methylbutan-1 provides a two-stage dehydrogenation of isopentane, contact condensation of the gas of the first stage dehydrogenation, the allocation of the resulting condensate isopentane-isoamylene fractions and division into isopentanol and isoamylenes fractions; the condensation of the contact strip of the second stage dehydrogenation, the stabilization of the obtained condensate by distillation emitting in the distillate fraction containing C3-C4- hydrocarbons, and as product - isoprene-isoamylene faction. The separation of the latter are extractive rectification on isoamylenes fraction which is returned to the second stage dehydrogenation, and isoprene fraction. From isopentanol faction clear rectification produce 3-methylbutan-1, which together with isoamylenes fraction served on the second stage dehydrogenation. On the stage of stabilization of the condensate of the second stage dehydrogenation in distillate together with C3-C4-hydrocarbons selected 3-neotnositsya improved the process of co-production of isoprene and 3-methylbutan-1, which are used in the IC industry and petrochemistry.

Closest to the proposed by its technical essence is a method of producing isoprene and 3-methylbutane a two-step dehydrogenation of isopentane, including contact condensation of the gas of the first stage dehydrogenation, the allocation of the resulting condensate isopentane-isoamylene fractions and division extractive rectification on isopentanol and isoamylenes faction, condensation, condensation of the contact strip of the second stage dehydrogenation, followed by distillation of the condensate of the second stage dehydrogenation emitting in the distillate fraction containing hydrocarbons WITH3-C4and as the product isoprene-isoamylene fraction, the separation of isoprene-isoamylene fraction by extractive rectification on isoamylenes fraction which is returned to the second stage dehydrogenation, and isoprene fraction.

The disadvantage of this method is the low quality of the obtained 3-methylbutan-1 (the content of the basic substance is not more than 80-95 wt.).

The technical challenge is to improve the quality of 3-methylbutane-1 and reduce energy costs.

The task dost the, including contact condensation of the gas of the first stage dehydrogenation, the allocation of the resulting condensate first stage dehydrogenation of isopentane-isoamylene fractions and division extractive rectification on isopentanol and isoamylenes faction, contact condensation of the gas of the second stage dehydrogenation, the stabilization of the resulting condensate of the second stage dehydrogenation rectification emitting in the distillate fraction containing hydrocarbons WITH3-C4and as the product isoprene-isoamylene fraction, the separation of isoprene-isoamylene fraction by extractive rectification on isoamylenes fraction which is returned to the second stage dehydrogenation, and isoprene, the distinguishing feature of which is that of isopentanol faction clear rectification produce 3-methylbutan-1 and it, along with isoamylenes fraction served on the second stage dehydrogenation stage condensate stabilization of the second stage dehydrogenation in the distillate together with hydrocarbons3-C4select 3-methylbutan-1 and obtained from the distillate by a clear rectification produce 3-methylbutan-1.

P R I m e R 1. On the dehydrogenation serves 150 g/h isopentenes carried out in a quartz reactor flow type, heated furnace, fluidized bed alimohammadi catalyst. The download size of the catalyst 40 cm3. The catalyst is pre-developed for 2 h in a stream of air at 650aboutWith the gradual decline in temperatures up to 580aboutC. Experiments are cycles.

The cycle includes: dehydrogenation 15 min, purge with nitrogen for 5 minutes, gradually raising the temperature to 650aboutWith in a stream of nitrogen for 20 min, the regeneration of the catalyst in this mode for 30 minutes, the temperature reduction in air flow to 580about20 min, purge with nitrogen for 5 min. flow rate of nitrogen, air and raw materials are 400 h-1.

Get the contact of the gas in the number 148,77 g/h composition, wt. hydrogen 3,47; hydrocarbons3-C43,88; isopentane 48,60; isoamylene 35,91; n-pentane 1,90; n-penten 0,06; isoprene 2,88; piperylene of 0.18. The total yield of isoprene and isoamylenes is: missed isopentane to 39.6 wt. on turned of 79.5 wt. The percentage of raw materials, converted into coke, of 0.82 wt. Forth from the condensate of the first stage dehydrogenation extractive rectification allocate isoamylenes fraction composition, wt. hydrocarbons WITH40,2; isopentane 0,3; isoamylene 84,8; n-pentane to 4.8; n-penten 8,5; isoprene and 1,4 isopentanol faction sotoudeh as one (K=1 and K=2). The mode and parameters of the process are the following: the amount of power 20-50 g/h

The total number of plates 71 PCs

Reflux the number 95-130

Temperature

in Cuba colon - HN K-1 60-65aboutWith on top of K-2 40-45aboutWITH

The pressure in the cube K-1 0,15-0,19 MPa

The pressure on top of K-2 0,12-0,14 MPa

In this mode, receive the distillate containing 80-95 wt. 3-methylbutan-1 at a residual content of his columns in the cube K-1 0,1-0,5 wt. Dedicated 3-methylbutan-1 isoamylenes faction when its content in isoamylenes fraction of 3.3 wt. served on the second stage dehydrogenation.

The dehydrogenation isoamylenes fraction (flow isoamylenes faction 144,75 g/h) is carried out in the flowing metal reactor of steel grade HT. The reactor calciumsilicate catalyst (fraction 2-3 mm) are placed in a vertical furnace with a fluidized bed of sand and the system of indirect temperature control (temperature dehydrogenation 590-650aboutC).

Experiments are performed cycles: dehydration regeneration. The cycle includes the steps: dehydrogenation 15 min, purge steam 1 minute Isoamylenes fraction is diluted with steam at a ratio of 1:20. The download size of the catalyst 40 cm3. The volumetric feed rate of 350 h-12 3.50 Hydrocarbons3-C42.06 to Isopentane 0.59 Isoamylene 48,00 n-Pentane 5,38 n-Pentane 6,15 Isoprene 31.90 Beef Cyclopentadiene 0.02 Piperidin 0,82

The yield of isoprene is, wt.

Missed isoamylene 38,78

on turned items 88,56

Raw material was placed in Cox 1,91

The condensate of the second stage dehydrogenation in the number 137,4 g/h composition, wt. Hydrocarbons WITH3-C42,17 Isopentane 0,62 Isoamylene 47,47 SMB 3,1 Isoprene 33,61 Cyclopentadiene 0.02 Piperidin 0,87 n-Pentane 5,66 n-Pentane 6,48

served in a column stabilization at the Department SMB together with the fraction of hydrocarbons WITH3-C4. This top of the column select 10,38 g/h fraction composition, wt. Hydrocarbons WITH3-C428,71 SMB 21,20 Isoamylene 40,56 Isopentane 2,88 Isoprene 1,83 n-Pentane 4,82 and bottom select 127,02 g/h isoprene-isoamylene fraction composition, wt. Isoamylene 48,03 Isoprene 36,21 SMB 1,62 Isopentane 0,43 n-Pentane 7,01 n-Penten 5,74 Cyclopentadiene 0.02 Piperidin 0,94 which is sent on extractive rectification, where separate isoprene, and isoamylenes faction return to the second stage dehydrogenation.

The fraction containing of 21.2 wt. SMB subjected to distillation, which is carried out in a laboratory setup periodic castledawson composition, wt. Hydrocarbons WITH3-C497,7 SMB 1.07 Isoamylene 1,2 Isopentane Traces of Isoprene 0,03

Then raise the temperature of the cube to 53aboutAnd the top to the 32aboutWith and select 95,73 g of the target fraction SMB composition, wt. Hydrocarbons WITH40,13 SMB of 98.2 Isopentane 0.5 Isoprene traces Isoamylene 1,17 Penten-1 Traces of Products of decomposition of DMF in this fraction are missing.

Output SMB at the stage of selection based on the obtained condensate of the second stage is:

F 100 45,82 Mac

P R I m m e R 2. The condensate of the second stage of the industrial process of dehydrogenation in the number 31717,9 kg/h composition, wt. Hydrocarbons WITH1-C2Traces of Hydrocarbons WITH3-C43.5 Isopentane 0,62 Isoamylene of 46.77 SMB 3.8 Isoprene 32,61 Cyclopentadiene 0.03 Piperidin 0.90 n-Pentane 6,10 n-Pentane 5,67 served in column 1, operating in the following modes:

The number of those

eroticheskih plates, 20 pcs.

The number of those

eroticheskih

plates in strengthening the purpose of part 10 PCs Reflux number 6

Pressure, ATA: top 3,2 cube 3,4

TemperatureaboutFrom the top 40 cube 70,6 power 65 While on top of the column select 3489,0 kg/h fraction composition, wt. Hydrocarbons WITH1-C2Traces of Hydrocarbons WITH3-C431,82 SMB 23,5 speakers. Isoamylene 48,31 Isoprene 36,33 SMB 1,36 Isopentane 0,45 n-Pentane 6,37 n-Penten 6,13 Cyclopentadiene 0.03 Piperidin of 1.02 which is sent on extractive rectification, where separate isoprene, and isoamylenes faction return to the second stage dehydrogenation.

The fraction containing 23,51% SMB served in a column operating in the following modes:

The number of those

eroticheskih plates 20 pcs.

The number of those

eroticheskih

plates in strengthening the purpose of part 10 pcs. Reflux 15

Pressure, ATA: top 8,0 cube 8,2

Temperature aboutFrom: top 40 cube 106,4 power 99,5 Top of the column select faction in the number 1137,5 kg/h composition, wt. Hydrocarbons WITH3-C497,5 SMB 0.75 Isoamylene 1.7 Isopentane Traces of Isoprene 0.05 a bottom 2351,2 kg/h fraction composition, wt. Hydrocarbons WITH3-C40,04 SMB 34,52 Isopentane 2,98 Isoamylene 50,06 Isoprene 3,69 n-Pentane 8,71 which is sent to the column 3, operating in the following modes:

The number of those

eroticheskih plates, pieces 55

The number of those

eroticheskih

plates in strengthening the purpose of parts, pieces of 35.5 Reflux number 40

Pressure, ATA: top 2,0 cube 3,1

TemperatureaboutFrom the top of the cube 40 61.5 power 57 the Top of this column are selected goods is SUB>40,14 p-Pentene 0.3 Isoprene Traces away From the cube isoamylenes fraction, which returns to the second stage dehydrogenation.

Output SMB at the stage of selection based on the obtained condensate of the second stage is:

F 100 59,25

The products of decomposition of DMF in the product fractions are missing.

The process described method can improve the quality SMB (basic substance content increased from 80-95 wt. to 97,6 is 98.2 wt. the products of decomposition of DMF in the product fractions are absent) and reduce energy costs at the stage of rectification allocating SMB from more concentrated solutions.

The process of co-production of ISOPRENE AND 3-METHYLBUTAN-1 the two-stage dehydrogenation of isopentane, including contact condensation of the gas of the first stage dehydrogenation, the allocation of the resulting condensate first stage dehydrogenation of isopentane-isoamylene fractions and division extractive rectification on isopentanol and isoamylenes faction, contact condensation of the gas of the second stage dehydrogenation, the stabilization of the resulting condensate of the second stage dehydrogenation, rectification emitting in the distillate coat is e isoprene-isoamylene fraction by extractive rectification on isoamylenes fraction, return to the second stage dehydrogenation, and isoprene, wherein isopentanol faction clear rectification produce 3-methylbutan-1 and it, along with isoamylenes fraction served on the second stage dehydrogenation stage condensate stabilization of the second stage dehydrogenation in the distillate together with the hydrocarbon, C3-C4select 3-methylbutan-1 and obtained from the distillate by a clear rectification produce 3-methylbutan-1.

 

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The invention relates to an improved method for producing a joint production of isoprene and 3-methylbutan-1, which are used in the IC industry and petrochemistry

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FIELD: petroleum chemistry, chemical technology.

SUBSTANCE: crude alpha-olefin is heated, raw vinylidene olefins are isomerized in the presence of catalyst and alpha-olefin is separated from isomerized vinylidene olefin by rectification. Separation of alpha-olefin is carried out for at least two successive steps at similar temperatures on top of vat and reducing pressure of rectifying column at each following step. Condensed phase removing from top of the rectifying column at previous step is fed to feeding zone of the following step and the rectifying column at top and vat section is sprayed. For spraying the top section of column the condensed phase removing from the top of rectifying column at the same step is used and for spraying the vat section of column the vat liquid of rectifying column at the same step is used. Separated alpha-olefin is purified additionally from oxygen-containing impurities by adsorption up to polymerization degree of purity. Raw heating, isomerization, separation and adsorption are carried out in atmosphere in inert gas. The unit used for treatment of alpha-olefin includes reactor for isomerization of vinylidene olefins in raw, rectifying column wherein feeding zone is joined with reactor outlet and wherein alpha-olefin of high purity degree is removed from the column top. The unit includes also at least one rectifying column for additional treatment of alpha-olefin of high purity from isomerized vinylidene olefins and adsorption column for separation of oxygen-containing impurities in alpha-olefin of high purity wherein the column inlet is joined with the top outlet of the last rectifying column used for additional treatment of alpha-olefin of high purity and outlet is used for removing alpha-olefin of the polymerization purity degree. Invention provides enhancing quality of the end product.

EFFECT: improved method for treatment.

8 cl, 1 dwg, 1 ex

FIELD: organic chemistry, petroleum chemistry, chemical technology.

SUBSTANCE: method involves preparing ethylene and hexane-1 from butene-1 by the exchange reaction of butene-1 and the isomerization reaction of synthesized hexane-3 to hexane-1. The parent material represents a mixed butene flow wherein butene-1 is isomerized to butene-2 after separation of isobutylene followed by the isomerization reaction of butene-2 to butene-1. Butene-1 is a raw for the exchange reaction.

EFFECT: improved preparing method, simplified technology process.

32 cl, 4 tbl, 4 ex

FIELD: chemistry.

SUBSTANCE: invention pertains to the method of obtaining 2-methyl-2-butene from isopentane, including gas phase dehydrogenation of isopentane in the dehydrogenation zone, extraction of the C5-fraction from contact gas, mainly consisting of isopentane, tert pentanes, isoprene impurities and other hydrocarbons and obtaining a stream from it, mainly consisting of 2-methyl-2-butene, with use of a liquid phase isomerisation catalyst in a C5-fraction 2-methyl-1-butene in 2-methyl-2-butene and distillation. The method is characterised by that, the above mentioned C5-fraction, possibly containing extra piperylene and 2-pentene, directly or after distillation from the larger part of 2-methyl-2-butene, undergoes liquid phase hydroisomerisation in the presence of a solid catalyst, containing group VIII metal(s), capable of simultaneous catalysing hydrogenation of pentadienes, isoprene and possibly, piperylenes, and positional isomerisation of tert pentenes, preferably with subsequent additional isomerisation of 2-methyl-1-butene in 2-methyl-2-butene on a sulfocationite catalyst, and distillation with output of a distillate stream of mainly isopentane, containing not more than 1.0% mass, preferably not more than 0.2% mass of pentadiene(s), which are mainly recirculated in the hydrogenation zone, and output from the lower part of the recirculation stream of mainly 2-methyl-2-butene with impurities of n.pentane and possibly 2-pentenes. The invention also pertains to the method of obtaining isoprene from isopentane, which involves reaction of 2-methyl-2-butene, obtained from gas phase dehydrogenation of isopentane, with hydroperoxide with further conversion of the oxide or products of hydroxylation in isoprene.

EFFECT: obtaining 2-methyl-2-butene and isoprene from isopentane.

13 cl, 8 ex, 2 tbl, 3 dwg

FIELD: chemistry.

SUBSTANCE: invention relates to a method of dehydrogenating isopentane and isopentane-isoamylene fractions, carried out at atmospheric pressure in a water vapour medium via dehydrogenation-regeneration cycles in the fixed bed of a catalyst based on platinum and tin deposited on an aluminium-zinc spinel, characterised by that the catalyst used has average crystal size of 22-35 nm with the following content of components in wt %: platinum - 0.05-2.0, tin - 0.1-6.0, aluminium-zinc spinel - the rest. The dehydrogenation process is carried out at 560-620C, feed space velocity of the material of 300-500 h-1 in the presence of hydrogen and water vapour. The ratio material: hydrogen : water vapour equals 1 :0.5-2.0 :5-20 mol : mol : mol.

EFFECT: use of the method enables more efficient dehydrogenation of isopentane and isopentane-isoamylene fractions.

3 cl, 14 ex, 1 tbl

FIELD: chemistry.

SUBSTANCE: catalyst system component is obtained via mechanical activation of a solid mixture with the ratio of 2-ethyl hexanoate of group I metal:CrCl3>1:1 and heating the activated mixture to obtain the desired product. The ethylene oligomerisation catalyst system contains an organoaluminium compound of general formula AlR3, a complexing agent, a modifier, a solvent and a chromium-containing component obtained using the disclosed method. The ethylene oligomerisation method is carried out in the medium of a hydrocarbon solvent at temperature of 40-95C and ethylene pressure of 1-5 MPa in the presence of said catalyst system.

EFFECT: simple method of producing a component of catalyst systems for oligomerising olefins, high output of the product when oligomerising ethylene to hexene-1, high selectivity of the process and purity of hexene-1, low probability of secondary reactions.

4 cl, 1 tbl, 16 ex

FIELD: chemistry.

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1 cl, 1 tbl, 13 ex

FIELD: chemistry.

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EFFECT: use of disclosed method allows stable operation of reactor, improves heat removal and prevents clogging of reactor.

15 cl, 1 ex, 1 tbl, 3 dwg

FIELD: chemistry.

SUBSTANCE: invention relates to a process of separating hexene-1 from the mixture obtained in the reaction of section of the ethylene trimerization process, wherein mentioned mixture comprises ethylene, solvent, catalyst and ethylene trimerization products derived, including hexene-1. The method includes at least the following steps: a) separation in the first distillation column a mixture formed by the reaction of ethylene trimerization on top fraction containing ethylene and a bottoms fraction, b) separation of at least one other distillation column at least part of the stream bottoms fraction obtained in step a) for the top fraction containing hexene-1 and butene-1, and a bottoms fraction, c) separation in the final distillation column, at least part of the fraction containing hexene-1 and butene-1, get constant in step b), at the top fraction containing mainly 1-butene and a bottoms fraction containing mainly 1-hexene, wherein in said method: at least one portion of the stream bottoms fraction obtained in step b), is recycled to the a reaction section and at least one other portion of mentioned bottom fraction obtained in step b) is used in at least one recirculation loop, connecting the reaction section and the column of mentioned step b), mentioned recirculation loop allows to cool the reaction section and provide repeated of partial evaporation in mentioned column from step b).

EFFECT: process is more energy efficient.

18 cl, 8 ex, 2 dwg

FIELD: chemistry.

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EFFECT: increasing the yields of target product.

7 cl, 4 ex, 1 tbl

FIELD: chemistry.

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EFFECT: lower costs.

21 cl, 6 dwg, 2 tbl

FIELD: industrial organic synthesis.

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EFFECT: enhanced isoprene production efficiency and reduced specific consumption of raw materials.

1 dwg, 5 ex

FIELD: industrial organic synthesis.

SUBSTANCE: invention relates to production of isoprene for use in synthesis of isoprene rubber, butyl rubber, and isoprene-containing polymers used in tire industry and manufacture of general mechanical rubber goods. In the method of invention, isoprene is obtained by decomposition of 4,4-dimethyl-1,3-dioxan on calcium phosphate catalyst comprising synthesis of 4,4-dimethyl-1,3-dioxan by interaction of isobutylene-containing C4 fraction with formaldehyde-containing blend based on methanol-free formalin obtained by oxidation of methanol followed by rectification of formalin, accomplished at elevated temperature and pressure in presence of acid catalyst followed by separation of reaction medium into oil and water layers including extraction of organic products from water layer, isolation of 4,4-dimethyl-1,3-dioxan, unreacted C4-hydrocarbons, and high-boiling by-products from oil layer, condensation of 4,4-dimethyl-1,3-dioxan decomposition contact gas and isolating from condensate isoprene, unreacted 4,4-dimethyl-1,3-dioxan, recycling isobutylene and formaldehyde-containing water, performing also withdrawal of extracted water layer to be vacuum evaporated followed by sending evaporated water layer to preparation of formaldehyde-containing blend. Evaporation of extracted water layer containing acid catalyst is carried out at temperature of boiler wall in rectification column 80-105°C and residual pressure 0.015-0.025 MPa. Distillate is mixed with above-indicated formaldehyde-containing water and resulting mixture is subjected to two-step concentration of formaldehyde. Second-step distillate, namely recycle methanol, is sent to oxidation zone. Bottom residues of the second step of formaldehyde concentration and those of the extracted water layer evaporation are combined with methanol-free formaldehyde and acid catalyst continuously supplied as replenishment, after which used as formaldehyde-containing blend in the 4,4-dimethyl-1,3-dioxan synthesis. Concentration of acid catalyst is maintained between 1.60 and 1.75 wt %.

EFFECT: increased productivity and reduced material and power consumption.

2 cl, 1 dwg, 5 ex

FIELD: industrial organic synthesis.

SUBSTANCE: invention relates to production of isoprene for use in synthesis of isoprene rubber and butyl rubber used in tire industry and manufacture of general mechanical rubber goods. In the method of invention, isoprene is obtained by decomposition of 4,4-dimethyl-1,3-dioxan on calcium phosphate catalyst comprising synthesis of 4,4-dimethyl-1,3-dioxan by interaction of isobutylene-containing C4 fraction with aqueous formaldehyde solution in presence of acid catalyst to form reaction medium composed of oil and water layers followed by separation of oil layer into unreacted C4-hydrocarbons and 4,4-dimethyl-1,3-dioxan by rectification leaving bottom residue containing dioxan alcohols (high-boiling dioxan alcohols to be processed into additional product), separation of water layer, condensation of contact gas, and recovery of desired isoprene. Low-boiling part of hydrocarbons distilled off in processing of bottom residue of 4,4-dimethyl-1,3-dioxan rectification is separated and thus obtained lower product is discharged as a mixture of high-boiling dioxan alcohols, which constitute additional desired product, whereas upper product is combined with formaldehyde-containing blend fed into 4,4-dimethyl-1,3-dioxan synthesis zone. Acid catalyst utilized in synthesis of 4,4-dimethyl-1,3-dioxan is mixture of oxalic and phosphoric acids at weight ratio between 2:1 and 1:1, whereas summary concentration of acids in formaldehyde-containing blend is maintained between 1.5 and 2.5 wt %. Remaining high-boiling fraction of hydrocarbons taken off in processing of bottom residue of 4,4-dimethyl-1,3-dioxan rectification, which are mixture of heavy residue and high-boiling alcohols, are taken off in the form of by-product.

EFFECT: enhanced isoprene production efficiency and reduced corrosion of technique, clogging with salts and tars, produced useful dioxan alcohols, and reduced specific consumption of raw materials.

1 dwg, 3 ex

FIELD: hydrogenation-dehydrogenation catalysts.

SUBSTANCE: invention relates to catalysts used in isoamylenes-into-isoprene dehydrogenation process and contains, wt %: iron oxide 62-75.4, potassium carbonate 12-21.5, chromium oxide 1-3, potassium hydroxide 0.5-2.5, sulfur 0.1-2.0, ammonium nitrate 0.1-2.0, silicon dioxide 1-5, calcium carbonate 1-5, and cerium nitrate 1-3.

EFFECT: increased mechanical strength, resistance to saturated steam and moisture, and stability during long-time operation.

3 ex

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