Method of production of the pure isobutene

FIELD: chemical industry; methods of production of the pure isobutene out of the isobutene-containing mixture.

SUBSTANCE: the invention is pertaining to the method of production of the pure isobutene out of the isobutene-containing mixture predominantly - out of hydrocarbon С4 with usage of the catalysis by the strong-acid cationite(s) including the liquid-phase interaction of the isobutene with the water at the temperature of from 60 up to 130°С in one or several sections at the stage of hydration, delamination of the being withdrawn from it stream(s), distillation of the unreacted hydrocarbons С4 from the hydrocarbon layer, decomposing of the tret-butanol in the section(s) at the stage of dehydration, separation of the formed isobutene from the water and its) purification and characterized by that isobutene and the total amount of the returned from the stage of dehydration fresh water is fed in the section of hydration in the total molar ratio from 1:0.4 up to 1:20, and it is preferential from 1:1 up to 1:5, in the straight-flow or bubbling mode in the absence of the emulsifier hydrate from 30 up to 97 % of isobutene. From the stage of the hydration in the stage of the dehydration at least one-third of the produced tret-butanol is fed in the stream, separated by the rectification from the layer of the unreacted hydrocarbons and containing from 5 up to 30 mass % of the water, and, possibly, the rest amount - in the stream of the water layer, at the total content of the different, than the isobutene, the hydrocarbons not exceeding their admissible quantity in the target isobutene, and from the stage of the dehydration the water at least partially is returned into the stage of the hydration. The presented method requires the low power input and the low metal input.

EFFECT: the invention ensures the low power input and the low metal input.

14 cl, 2 dwg, 4 ex

 

The invention relates to the field of production of concentrated isobutene of isamuanoguchi mixtures predominantly hydrocarbon, C4.

Known [Pasiecznik and other Album of technological schemes of the main production of the synthetic rubber industry. L.: Chemistry, 1986, p.75-77] industrial method of obtaining a concentrated isobutene of isamuanoguchi mixtures of hydrocarbons, C4with cationite catalysis, in which the hydration of isobutene is carried out in countercurrent reaction-extraction mode with a molar ratio of water supply:isobutene (in C4mix) ˜70:1. The resulting tert-butanol display consisting of two threads: unreacted hydrocarbons and water, of which tert-butanol allocate the rectification in the form of mixtures thereof with water, and then tert-butanol in the mixture with water is subjected to dehydration in reactive distillation mode, the resulting isobutane evaporated and purified by water washing, distillation and azeotropic dehydration.

The process can be complicated (includes at least 10 vessels) and energy-intensive. Energy intensity is defined largely by the need to process extremely large water and water-tert-butanolic flows. Tert-butanol difficult to separate from water because of the unfavorable phase equilibria and education azeotrope with water.

<> A possible variant of this method by applying a diluted aqueous solution of tert-butanol are added after degassing zone dehydration of tert-butanol. The process in this case is also complicated and energy-intensive because of the need for heating and subsequent cooling (when you return to the zone of hydration) very large water flows.

In addition, these options require excessive loading of the catalyst and the large size of the reaction zones of hydration and dehydration, and uniform distribution of isobutene (C4-mixture) and water causes difficulties.

Found the way in which the feed and recirculation of water (heating and cooling) repeatedly reduced, and greatly reduced the required catalyst loading and the size of the reactors hydration and dehydration.

The method of obtaining pure isobutene of Isobutyraldehyde mixture predominantly of hydrocarbons, C4using a strongly acidic catalysis(and) cation exchange resin(s), including liquid-phase interaction of isobutene with water at a temperature of from 60 to 130°in one or more zones at the stage of hydration, exfoliation output(s) from it flow(s), the Stripping of unreacted hydrocarbons With4from the hydrocarbon layer, the decomposition of tert-butanol in the zone(s) at the stage of dehydration, separation of the resulting isobutane from water and PTS is STCU, the difference is that isobutene and the total number returned from the stage of dehydration and/or fresh water is fed to the area(s) of hydration in the total molar proportions of from 1:0.4 to 1:20, preferably from 1:1 to 1:5, flow or bubble mode in the absence of emulsifier hydratious from 30 to 97% of isobutene, from the stage of hydration on stage dehydration of at least one third of the obtained tert-butanol served in the thread allocated by the rectification of the layer of unreacted hydrocarbons and containing from 5 to 30 wt.% water, and possibly, the rest of the flow of the aqueous layer, the total content other than isobutene, hydrocarbons do not exceed their allowable number in the target isobutene, and with the stage of dehydration of water at least partially return to the stage of hydration.

As a technical solutions that contribute to the implementation of the method according to claim 1 claims, we affirm means, characterized in that:

- water layer stage of hydration, including tert-butanol, at least partially, preferably after cooling, return to the zone(s) hydration and possibly also in the intermediate section, and the remaining amount of the specified layer, preferably after degassing together with degassing tert-butanol, serves on the stage of dehydration;

- part of the flow of unreacted hydrocarbons to the/or after distillation from tert-butanol recycle in the area(s) of hydration;

- part of the stream of unreacted hydrocarbons after distillation from tert-butanol carry out the extraction of tert-butanol from the aqueous layer of the reaction(s) zone(s) hydration with the subsequent return of the obtained tert-butanesthere stream to the distillation of the unreacted hydrocarbons4from tert-butanol;

- recycled(e) water(f) thread(s) from the stage of dehydration of tert-butanol, fresh water and possibly isopotential(s) hydrocarbon(s) a mixture of(I) at least partially served at the entrance to the area(s) of hydration, and the remaining amount is preferably served in its(their) intermediate section;

- hydration is carried out in tubes cooled(s) shell-and-tube(s) unit(s) and/or adiabatic(s) unit(s);

- water(e) and/or hydrocarbon(s) thread(s) served in the area(s) of hydration separately or together through the dispersing device, ensuring an even distribution between the tubes or in the cross section of the reaction zone;

the catalyst in zone(s) hydration support is immersed in the liquid when liquid flows downward over the catalyst support layer of liquid is not less than 5 mm, and dispersible stream served with speed, providing mixing of the specified layer, so that in different parts of the catalyst, the liquid flows with the same molar balance is the group of water and isobutene;

- water and hydrocarbon streams are served mainly in the middle part of the apparatus of hydration and maintain the flow of fluid in the bottom of from the top down, and in its upper part from the bottom up with subsequent delamination emanating from the zone(s) hydration flows;

- dehydration of tert-butanol is carried out in the reaction zone, connected by flows of liquid and vapor at least with exhaustive distillation zone, in which the distillation of isobutene and tert-butanol from water, and preferably with the strengthening of the distillation zone of the distillation of isobutene from tert-butanol and water, and the reaction zone preferably has a square cross-section, at least 1.4 times greater cross-sectional area of the distillation(s) zone(s) and is in common with distillation(s) area(s) column apparatus or separately;

part of water, from which pre-distilled tert-butanol, served above the reaction zone in an amount to provide suppression of di - and oligomerization of isobutene;

- formed in a small amount of dimers and possibly trimers of isobutene removed by withdrawal of the side stream from exhaustive distillation zone and/or by sedimentation from the water preferably after mixing with the hydrocarbon(s)having a boiling point above 20°C;

- use fine-grained the th sulfonation and/or coarse-grained sulfonation, maybe molded in the form of mass transfer nozzle;

- returned from the stage of dehydration of the aqueous stream is subjected to removal of impurities preferably by trail and/or anionite cleanup.

The use of the invention illustrated in figures 1 and 2 and examples. These figures and examples do not exclude other modes of use of the invention with respect to claim 1 of the claims.

Figure 1 source IsolatedStorage the mixture flows through line 1 and is fed into the hydration zone (reactor R-1) on line 1A (below) and, possibly, lines 15 and 1B. Fresh water (steam condensate) entered on line 2, is connected with the flow of water recycled after dehydration (thread 12A) and then fed into the R-1, preferably along the lines 2A, 2B, and possibly along the line 2B, connecting with the recirculated flow 12.

Aim at the top of the R-1 streams are combined, if necessary, heated and injected into P-1 line 3 through the dispersing device (injector). From R-1, the reaction mixture output line 4, defend in WITH and the entire bottom layer or the greater part of recycle in R-1 line 5 (3). Perhaps a small part of the water output layer, preferably neutralized and served in the column K-1 or K-2.

The hydrocarbon layer from the output line 6 and completely or mostly served in the distillation column K-1 on line 6A, and predpochtitelno previously neutralized. Perhaps part of the flow 6 along the line 6b recycle input and/or lateral entry in R-1.

Of the K-1 top output line 7 as unreacted distillate hydrocarbons which are wholly or partially output line 7a. Perhaps part of the flow 7 through line 7b (hereinafter 1A, 3) is fed to the input in R-1. Bottom line 8 output stream mainly containing tert-butanol, partially water and possibly an admixture of hydrocarbons. Perhaps by condensation of stream 7 is peeling a small amount of water is removed from the reflux vessel.

Stream 8 is available on line 8b in column K-2 for additional degassing or directly on line 8b (hereinafter, 11, 11a, 11b) is fed to the dehydration zone (R-2).

From K-2 gases output lines 9 and degassed tert-butanolic flow output line 10 and line 11 (hereinafter 11a, 11b) are served in the dehydration reactor.

Bottom comprehensive column K-3 output line 12 of the water. Perhaps on line 13 output side stream with a high content of di - and oligomers of isobutene, which is preferably mixed with water (line 12B) and the hydrocarbon solvent (line 14, and line 15 deduce the solution of the dimers in the hydrocarbons and the water line 12g attached to her recirculated stream 12A. Stream 12A recycle in R-1 (line 12A, 2A, 2B, 2C), preferably pre-exposing clean up when the Yessei (iron etc) using ionite filter(s).

Perhaps a small part of the thread 12 on the line served on top of R-2 to suppress di - and oligomerization of isobutene.

Top-To-4 line 16 or directly on top of the R-2 through line 17 output stream isobutene with impurities (own tert-butanol). Its on line 18 serves in a distillation column K-5. Bottom-To-5 output line 19 of the flow of impurities, which output line 19a and/or recycle line 19b (hereinafter 11a, 11b) in R-2.

The top-5 output line 20 net isobutene, which may optionally subjected to washing (not shown), and drying, and on line 21 output of the target product.

In figure 2 the node hydration differs from figure 1 that the main number isopotential hydrocarbon mixtures of recycled water layers of the separator-sump (WITH) and possibly recycled water from the stage of dehydration is served in the middle part of the hydration reactor R-1. The flow of fluid in zones C-1 and C-3 from top to bottom and in zones C-2 and C-4 from the bottom up. Outflows 4A and 4B rasclaat respectively in the CO-1 and CO-2. Their water layers in whole or greater part of the recycle lines 5A and 5B in the R-1, mostly (or completely) in the middle part of the line 3.

Recirculated water stream from the dehydration served in the R-1, possibly with the flow of fresh water, mainly in the intermediate section along lines 2B and 2C and/or in the middle is the part on line 2A (3). Entered in P-1 threads thoroughly dispersed.

Hydrocarbon layers of CO-1 and CO-2 served on lines 6A and 6b (hereinafter 6b) in a distillation column K-1 (preferably after neutralization). Perhaps some of them served (return) in the middle part of the K-1 on line g

Top-To-1 output line 7 a stream of unreacted hydrocarbon, which is completely or partially removed along the line 7a.

Perhaps part of the flow 7 recycle line 7b R-1 (enter on line 9). Perhaps by condensation of stream 7 is peeling a small amount of water is removed from the reflux vessel.

Bottom-To-1 output lines 8 a stream containing predominantly tert-butanol and partially water which is sent to the dehydration of tert-butanol on line 8A (mostly) and possibly lines 8b and 8C. In the presence of a stream of 8 significant amounts of hydrocarbons With4additional Tegaserod (not shown).

Node dehydration of tert-butanol includes a column K-2, from which the output side streams 10 and 11 (preferably steam or vapor state), served in reactors R-1 and R-2 with a sulfonic cation exchanger. Perhaps in the R-1 and R-2 also serves part(and) water flow 12 lines 12g and d. From R-1 and R-2 of the reaction mixture returned to K-2 on the lines 14 and 15.

From below By-2 output stream 12, which preferably after cleaning) re cirkuliruet in R-1. Perhaps, from the bottom of the K-2 output stream 13 to output dimers and trimers of isobutene. It is mixed with water (stream 12B) and the hydrocarbon solvent (stream 17A) and deduce the solution of dimers (and trimers) in the indicated solvent (line 18a) and the water flow 12V attach to the thread 12A.

Top K-2 output line 16 of the flow of concentrated isobutene, which is directed to additional cleaning and drying carried out similar to that described in example 1.

Example 1

Processing is carried out according to the scheme in figure 1, with the characteristic that as Hydrator K-1 using shell-and-tube apparatus, tubes filled with sulfonic cation exchanger based on a copolymer of styrene and divinylbenzene, Amberlyst 35 (particle size of 0.4-1.3 mm, static volumetric capacity SOY=5.1 mg EQ/g). The temperature of 70-75°C, a pressure of 12 ATA. The amount of catalyst 25 kg

In the zone of dehydration using molded selfactivity catalyst KU-PPP in the form of rings (outer diameter 4-6 mm, 6-8 mm in length, SOY=3.7 mg EQ/g). The temperature in the dehydration zone 90°C, a pressure of 4.2 ATA, the amount of catalyst 60 kg

The recirculation of unreacted hydrocarbons in the reactor hydration is omitted.

The filing of the original hydrocarbon mixture of 100 kg/h (45% isobutene, the rest is mainly isobutane).

The supply of fresh water is not less than 0.2 AU (to replenish losses).

The feed to the reactor hydration water recycled after dehydration of tert-butanol - 18.7 kg/h (including 1 wt.% tert-butanol). The mass ratio of incoming to the node in the hydration water (not including recycling of the aqueous layer) and the source of the hydrocarbon fraction 0,188:1. The molar ratio entering site water and isobutene with the original hydrocarbon fraction MO=1.3 to 1 (i.e. 54 times less than in the prototype).

Water and hydrocarbons is administered jointly through the dispersing nozzle. Above the layer of the catalyst support layer of liquid height 15 mm

Thread 6≡6A is 119,2 kg/h and contains : 11.3% of isobutene, 46.2% of other hydrocarbons4(mainly isobutane), 34.9% of tert-butanol, 7,3% water, 0.3% dimer isobutene.

Thread 7≡7a is 68,6 kg/h and contains 19.7% of isobutene, 80.2% of other hydrocarbons4(mainly isobutane) and 0.1% tert-butanol.

Conversion isobutene when hydration is 70%.

The dehydration zone contains 45 kg molded ionite catalyst KU-PPP on the basis of a mixture of a copolymer of styrene and divinylbenzene and polypropylene in the form of rings (diameter 4-6 mm, 6-8 mm in length, SOY=3,4).

When dehydration from the bottom of column K-3 output of 17.5 kg/h of water containing ˜1% tert-butanol and deduce the lateral flow (1.8 kg/h), containing 22.5% of dimers of isobutene, 68,5% water and 9% tert-butanol. In the cleaning zone from dimers serves 3,4 to the/h gasoline. Perhaps the threads together in the recirculated stream 12A constituting 18.8 kg/h

Stream 21 is to 31.2 kg/h and contains 99.95% of isobutene, ≤0.05% of other hydrocarbons, C4that is less than 0,002% tert-butanol and about 0.001% is water.

Example 2

The processing carried out according to figure 1. For hydration using adiabatic reactor with three reaction zones containing a total of 35 kg of fine-grained catalyst KSM-2 (particle size of 0.4-1.3 mm, SOY=4,2).

The filing of the original mixture of 1-100 kg/h (45% isobutene and the rest from other hydrocarbons With4mainly isobutane).

The supply of fresh water (stream 1) 0.1 kg/h of the Total water supply to the site of hydration - mainly after the recycle dehydration of tert-butanol and 26.9 kg/h (not including recycling water tert-butanole flow 5). Thus, the mass ratio of water supplied and the original hydrocarbon mixture 0,269:1. The molar ratio of water supply and isobutene 1,49:1.

The ratio of threads 5 and 6 is 3:1. For entry into R-1 recycle 35% of the hydrocarbon stream 7. Supplied the original hydrocarbon mixture is spread on the threads 1A, 1B and 1C in the ratio of 50:30:20. Water flow 12A distribute between the lines (inputs) 2A, 2B and 2C in the ratio of 40:35:25.

The supply of water and hydrocarbon streams in the reaction zone are using nozzles. The temperature in the reaction zone R-1 - 70-80°C. inverse of isobutene in the process of 82%.

Mass flow 6≡6A - 154 kg/h composition: 63,1% hydrocarbons With4, and 31.2% tert-butanol, and 5.5% water, 0.2% dimer isobutene. The mass inferred hydrocarbon stream 7a - 63,2 kg/h composition: 12.8% isobutene, 87.1% of other C4 hydrocarbons (mainly isopentane), 0,1% tert-butanol.

Mass flow 11 (approximately equal to the mass flow 8) - 56,8 kg/h Composition: 84,5% tert-butanol, 15,0% water, 0.5% of dimers of isobutene, ≤0.02% hydrocarbons With4.

In R-2 downloaded coarse catalyst "sulfonation on silica gel". The particle size of 0.4-0.5 mm, SOY=4.2V. Catalyst loading - 64 kg Temperature in the zone 78-84°C.

Mass flow 12A - 26.8 kg/h consisting of 99.5% water and 0.5% tert-butanol.

The stream output 13 - 1.2 kg/h separation from dimers of isobutene similar to example 1.

Mass flow 21 - 36,3 kg/h composition: 99.95% of isobutene, 0.04% of other hydrocarbons With4(mainly 2-butenes), ≤0,001% tert-butanol, ≤0.001% is water.

Example 3

The processing carried out analogously to example 2. Unlike example 2, the reactor R-1 use molded catalyst KU-PPP in the form of rings (size 4-6 mm, 6-8 mm in length, SOY=3,4).

The total loading of catalyst in the R-1 is 88 kg (chosen to match the conversion example 2).

The obtained results are almost similar to example 2.

Example 4

The processing carried out according to figure 2. For hydration used reactor with four reaction zones and submission of the principal amount of the original hydrocarbon mixture in the middle of the reactor.

In the R-1 catalyst Purolite ST-175 (particle size of 0.4-1.4 mm, SOY=5,0). The total loading of catalyst in the R-1 is 36 kg

The hydrocarbon feed With4-faction (thread 1) - 100 kg/h (45% isobutene, 11.6% butane, 24.3 percent 1-butene, 19.1% of 2-butenes. The flow in the R-1 water flow 12A recycled after dehydration of tert-butanol, 13.6 kg/h of fresh water - 0.1 kg/h

The mass ratio of the sum of these streams and hydrocarbon - 0,137:1. The molar ratio of water in these water flows and isobutene in the amount of 0.96:1.

Threads 5A and 15 recycle basically in the middle of the reactor. The supply amount of threads 12A and 1 are distributed between lines 2A, 2B and 2C in the ratio of 40:30:30. The filing of the original hydrocarbon mixture 1 is distributed between threads 1A, 1B and 1C in the ratio of 70:15:15.

The temperature in the reaction zone R-1 - 70-80°C. Conversion isobutene in the process is 55%.

The number of threads 6A and 6b - 56.7 kg/h, flow 6V - to 113.4 kg/h composition: 65.9% of hydrocarbons With4, 29,1% tert-butanol, 4,8% water, 0.2% dimer isobutene.

The number of stream 7≡7a - 75,2 kg/h composition: 26.9% of isobutene, other hydrocarbons With4˜73,1%, tert-butanol ≤0,05%.

Thread count 8 - 38,1 kg/h composition: 80.6% of tert-butanol, 19,0% water, 0.4% dimer isobutene, other hydrocarbons With4≤0,03%.

The dehydration is carried out in the system, including rectify the operating column K-2 and the side reactors R-1 and R-2, containing sulfonation with grain size of 1-1 .5 mm (SOY=5,1). The loading of catalyst in each reactor 25 kg. Catalyst in R-1 and R-2 are immersed in the liquid. The threads 10 and 11 of the By-2 output mainly in the steam mixed with the liquid) state.

Bottom-To-2 line 12 output stream. A small part of it is served in reactors R-1 and R-2 on the lines 12g and d. Side of the lower part of the K-2 output stream 13 to output the dimer isobutene.

The mass of the recirculated in the area of hydration thread 12A is 13.6-13.7 kg/h consisting of 97.8% water and 2.2% tert-butanol.

Weight displayed on top of K-2 stream 16 is 24,6 kg/HR Concentration of isobutene in it for the amount of hydrocarbons4- 99,94%.

1. The method of obtaining pure isobutene of Isobutyraldehyde mixture predominantly of hydrocarbons4using a strongly acidic catalysis(and) cation exchange resin(s), including liquid-phase interaction of isobutene with water at a temperature of from 60 to 130°in one or more zones at the stage of hydration, exfoliation output(s) from it flow(s), the Stripping of unreacted hydrocarbon, C4from the hydrocarbon layer, the decomposition of tert-butanol in the zone(s) at the stage of dehydration, separation of the resulting isobutane of water and its purification, characterized in that isobutene and the total number returned from the stage of dehydration and/or fresh water is up in the area(s) of hydration in the total molar proportions of from 1:0.4 to 1:20, preferably from 1:1 to 1:5, flow or bubble mode in the absence of emulsifier hydratious from 30 to 97% of isobutene, from the stage of hydration on stage dehydration of at least one third of the obtained tert-butanol served in the thread allocated by the rectification of the layer of unreacted hydrocarbons and containing from 5 to 30 wt.% water, and possibly, the rest of the flow of the aqueous layer, the total content other than isobutene, hydrocarbons do not exceed their allowable number in the target isobutene, and with the stage of dehydration of water at least partially return to the stage of hydration.

2. The method according to claim 1, characterized in that the aqueous layer stage of hydration, including tert-butanol, at least partially, preferably after cooling, return to the zone(s) hydration and possibly also in the intermediate section, and the remaining amount of the specified layer, preferably after degassing together with degassing tert-butanol, serves on the stage of dehydration.

3. The method according to claim 1, characterized in that the portion of the stream of unreacted hydrocarbons before and/or after the distillation from tert-butanol recycle in the area(s) of hydration.

4. The method according to claim 1, characterized in that part of the stream of unreacted hydrocarbons after distillation from tert-butanol carry out the extraction of tert-butanol from the aqueous layer reacts the Onna(s) zone(s) hydration with the subsequent return of the obtained tert-butanesthere stream to the distillation of the unreacted hydrocarbons 4from tert-butanol.

5. The method according to claim 1, characterized in that the recirculated(e) water(f) thread(s) from the stage of dehydration of tert-butanol, fresh water and possibly isopotential(s) hydrocarbon(e) a mixture of(I) at least partially served at the entrance to the area(s) of hydration, and the remaining amount is preferably served in its(their) intermediate section.

6. The method according to claim 1, characterized in that the hydration is carried out in tubes okhlazhdennogo(s) shell-and-tube(s) unit(s) and/or adiabatic(s) unit(s).

7. The method according to claim 1, characterized in that the water(e) and/or hydrocarbon(s) thread(s) served in the area(s) of hydration separately or together through the dispersing device, ensuring an even distribution between the tubes or in the cross section of the reaction zone.

8. The method according to claim 1, characterized in that the catalyst in zone(s) hydration support is immersed in the liquid when liquid flows downward over the catalyst support layer of liquid is not less than 5 mm, and dispersible stream served with speed, providing mixing of the specified layer, so that in different parts of the catalyst, the liquid flows with the same molar ratio of water and isobutene.

9. The method according to claim 1, characterized in that the water and hydrocarbon streams are served mainly in the middle part of the apparatus hidratacion support the flow of fluid in the bottom of from the top down, and in its upper part from the bottom up with subsequent delamination emanating from the zone(s) hydration threads.

10. The method according to claim 1, characterized in that the dehydration of tert-butanol is carried out in the reaction zone, connected by flows of liquid and vapor at least with exhaustive distillation zone, in which the distillation of isobutene and tert-butanol from water, and preferably with the strengthening of the distillation zone of the distillation of isobutene from tert-butanol and water, and the reaction zone preferably has a square cross-section, at least 1.4 times greater cross-sectional area of the distillation(s) zone(s) and is in common with distillation(s) area(s) column apparatus or separately.

11. The method according to claim 10, characterized in that a portion of water from which previously removed tert-butanol, served above the reaction zone in an amount to provide suppression of di - and oligomerization of isobutene.

12. The method according to claim 1, characterized in that formed in a small amount of dimers and possibly trimers of isobutene removed by withdrawal of the side stream from exhaustive distillation zone and/or by sedimentation from the water preferably after mixing with the hydrocarbon(s)having a boiling point above 20°C.

13. The method according to claim 1, characterized in that the use of fine-grained sulfonation and/or coarse-grained sulfonation possibly formed in the form of a mass transfer packing.

14. Pic is b according to claim 1, characterized in that the return from the stage of dehydration of the aqueous stream is subjected to removal of impurities, preferably by trail and/or anionite cleanup.



 

Same patents:

FIELD: organic chemistry, chemical technology.

SUBSTANCE: invention relates to a method for synthesis of styrene. At the first step the method involves interaction of ethylbenzene hydroperoxide with propene in the presence of catalyst to yield propylene oxide and 1-phenylethanol followed by separate treatment of reaction flow and removing propylene oxide. At the second step the method involves interaction of 1-phenylethanol-containing distillate with a heterogenous dehydration catalyst at temperature 150-320°C to obtain styrene. Distillate contains 0.30 wt.-%, not above, compounds of molecular mass at least 195 Da. Invention provides decreasing the content of by-side compounds in styrene and to enhance it's the conversion degree.

EFFECT: improved method of synthesis.

3 cl, 3 tbl

FIELD: industrial organic synthesis and catalysts.

SUBSTANCE: invention provides a method for processing methanol into dimethyl ether and liquid hydrocarbons, the latter being used as high-octane components of gasolines Ai-92, 95. Processing comprises contacting of raw material, in at least one step, in at least one reactor containing catalyst: Pentasil-type zeolite and binder, followed by cooling resulting products, condensation and separation thereof to isolate methanol conversion hydrocarbon gases, water, and desired products, after which cooled hydrocarbon gases are recycled to methanol conversion stage in at least one reactor. Catalyst is characterized by SiO2/Al2O3 molar ratio 20-100, content of sodium oxide not higher than 0.2%, and additionally contained silicon dioxide and zirconium dioxide at following proportions of components: 1.0-15.0% silicon dioxide, 1.0-5.0% zirconium dioxide, 20-70% zeolite, and binder - the balance.

EFFECT: increased yield of desired products and improved performance characteristics of catalyst.

4 cl, 5 tbl, 18 ex

FIELD: industrial organic synthesis.

SUBSTANCE: invention relates to production of alkylaryl hydroperoxides useful as starting material in production of propylene oxide and alkenylaryl. Process of invention comprises following stages: oxidation of alkylaryl compound to form reaction product containing alkylaryl hydroperoxide; contacting at least part of reaction product with basic aqueous solution; separation of hydrocarbon phase containing alkylaryl hydroperoxide from aqueous phase; containing at least part of above hydrocarbon phase with aqueous solution containing waste water, said aqueous solution containing less than 0.2% alkali metal and/or salt (determined as ratio of metal component to total amount of solution); and separation of hydrocarbon phase from aqueous phase. By bringing at least part of above hydrocarbon phase containing alkylaryl hydroperoxide into interaction with propylene and catalyst, alkylaryl hydroxide and propylene oxide are obtained. At least part of propylene oxide is then separated from alkylaryl hydroxide. Dehydration of at least part of alkylaryl hydroxide results in formation of alkenylaryl.

EFFECT: reduced amount of contaminating by-products in alkylaryl hydroperoxide preparation stage.

8 cl, 4 ex

FIELD: industrial organic synthesis.

SUBSTANCE: embodiments of invention are accomplished via liquid-phase dehydration of methyl phenyl carbinol-containing feedstock in presence of acid-type catalyst in column-type reactor-rectifier comprising still portion, built-in heat-exchanger, and rectification portion, volume of still portion constituting 80% of built-in heat-exchanger volume. Temperature of till portion of reactor-rectifier is 140-205°C and temperature in rectification portion 130-180°C. Advantageously, methyl phenyl carbinol-containing feedstock is supplied to and/or under built-in heat-exchanger and catalyst or mixture of catalyst with feedstock and/or still product is supplied to still portion at mixing. Linear velocity of reaction mass vapors within free cross-section of reactor is 0.05 to 0.9 m/s, residence time of styrene in reaction zone 0.05 to 50 sec, and residence time of still product in reactor 5 to 500 h.

EFFECT: increased conversion of feedstock and final product formation selectivity.

5 cl, 14 ex

The invention relates to a method for producing olefin vapor-phase dehydration of alcohols in the presence of a catalyst at elevated temperature

The invention relates to methods for production of 1-butanol (options), 1,3-butadiene and high-octane fuel from ethanol
The invention relates to the petrochemical industry and can be used to obtain propylene oxide (OP) and styrene

The invention relates to the field of production of isoprene and monovinylacetylene monomers
The invention relates to the petrochemical industry and can be used in the process of joint production of propylene oxide and styrene
The invention relates to an improved method of producing isoprene liquid-phase dehydration of 3-methyl-1,3-butanediol MBD at 105-135oIn the presence as catalyst of 2-40 wt.% phosphoric acid at a pressure of 1.1 to 3.0 ATA

The invention relates to the field of production of isoprene and monovinylacetylene monomers

The invention relates to the isomerization of olefins and can be used in the petrochemical industry

The invention relates to the production of concentrated isobutylene, in particular of isobutene, suitable for the production of butyl rubber

The invention relates to a method of separation of isobutene from a hydrocarbon fractions by treating them with water in the presence of an acid catalyst with the formation of tertiary butyl alcohol, which is then subjected to decomposition with obtaining isobutylene or used as a commercial product

FIELD: chemical industry; methods of production of the pure isobutene out of the isobutene-containing mixture.

SUBSTANCE: the invention is pertaining to the method of production of the pure isobutene out of the isobutene-containing mixture predominantly - out of hydrocarbon С4 with usage of the catalysis by the strong-acid cationite(s) including the liquid-phase interaction of the isobutene with the water at the temperature of from 60 up to 130°С in one or several sections at the stage of hydration, delamination of the being withdrawn from it stream(s), distillation of the unreacted hydrocarbons С4 from the hydrocarbon layer, decomposing of the tret-butanol in the section(s) at the stage of dehydration, separation of the formed isobutene from the water and its) purification and characterized by that isobutene and the total amount of the returned from the stage of dehydration fresh water is fed in the section of hydration in the total molar ratio from 1:0.4 up to 1:20, and it is preferential from 1:1 up to 1:5, in the straight-flow or bubbling mode in the absence of the emulsifier hydrate from 30 up to 97 % of isobutene. From the stage of the hydration in the stage of the dehydration at least one-third of the produced tret-butanol is fed in the stream, separated by the rectification from the layer of the unreacted hydrocarbons and containing from 5 up to 30 mass % of the water, and, possibly, the rest amount - in the stream of the water layer, at the total content of the different, than the isobutene, the hydrocarbons not exceeding their admissible quantity in the target isobutene, and from the stage of the dehydration the water at least partially is returned into the stage of the hydration. The presented method requires the low power input and the low metal input.

EFFECT: the invention ensures the low power input and the low metal input.

14 cl, 2 dwg, 4 ex

Up!