For separating and purification of 1,3-butadiene from c4-carbohydrate mixtures

FIELD: chemistry.

SUBSTANCE: invention refers to the method of separating and purification of 1,3-butadiene from the mixture consisting mainly of C4-carbohydrates and containing 1,3-butadiene and C4-carbohydrates that differ from the former by the number of unsaturated bonds and/or α-acetylene protons including at least (an) area(s) of extractive rectification with the polar extractant, denudation and ordinary rectification that is characterized by the fact that at least a polar spirit with the boiling point over 120°C is used as the mentioned extractant; stripping of C4-carbohydrates from the areas of extractive rectification and denudation of the mentioned extractant is performed under the high pressure from 3.5 to 6.5 at, at least into the lower part and/or into the boiler(s) of the extractive rectification area(s) the carbohydrate intermediate desorbent with the boiling point from 27 to 85°C is introduced in the amount that provides its content in the cube(s) of the high pressure denudation area(s) from 3 to 30 % weight; then the intermediate desorbent is stripped from the greater part of the extractant in the low pressure denudation area with 1.0-2.0 at; the extractant is fed back to the upper part of the extractive rectification area(s) and the intermediate desorbent to at least the mentioned point(s) of extractive rectification, and 1,3-butadiene undergoes additional purification from chemical impurities by means of rectification, supposedly with the small amount of extractant.

EFFECT: reduction of losses of 1,3-butadiene and improvement of the processing and economical efficiency.

10 cl, 3 tbl, 3 ex, 3 dwg

 

The invention relates to the field of extraction and purification of 1,3-butadiene from mixtures of predominantly C4-hydrocarbons containing 1,3-butadiene and C4-hydrocarbons, differing from it by the number of unsaturated bonds and/or α-acetylene protons. More specifically the invention relates to the field of extraction and purification of 1,3-butadiene using extractive distillation, Stripping, conventional rectification and possibly selective hydrogenation of α-acetylenic hydrocarbons.

Known methods [H.Ulmann, Encyklopädia der Technischen Chemie, 4-th Edition, 1975, vol.9, p.1-18; S.Ogura, T.Onda, Advances in C4-Hydrocarbons Processing; AIChE National Meeting, 1987, Aug., 16-19; Pasiecznik, Van, Limpopo. Album technological schemes of the main industries of the UK. L.: Chemistry, 1986, p.14-35] division C4-hydrocarbons, distinguished by the number of unsaturated linkages by extractive distillation in the presence of a polar organic or their mixtures with water followed by desorption of the more unsaturated hydrocarbons from the extractant.

Known methods [Pasiecznik and others, ibid, p.23-35; Shuvalov. Isolation and purification of monomers for synthetic rubber. L.: Chemistry, 1987, p.93-104] isolation and purification of 1,3-butadiene from mixtures containing 1,3-butadiene and C4-hydrocarbons, differing from it by the number of unsaturated linkages and/or α-acetylene protons by TLD the military extractive distillation with a polar solvent and subsequent distillation of 1,3-butadiene from the first propina, output from the distillate, and then from α-acetylenes C4and metrolina displayed in the composition of the cubic residue.

As polar extractants for the specified extractive distillation proposed acetonitrile, methoxypropionitrile, N,N-dimethylformamide, N,N-dimethylacetamide, N-organic N-formylmorpholine, sulfolan and their mixtures with small (up to 10% wt.) amount of water. Lack of acetonitrile (TKip81,6°C) is the formation of azeotropes with hydrocarbon, C4from which the acetonitrile is usually to wash with water, and then select it by distillation from water solutions.

High-boiling polar solvents do not form azeotropes with C4-hydrocarbons, however, the industrial processes of extraction and purification of 1,3-butadiene with high boiling extractants have another drawback. When desorption of them C4-hydrocarbons by condensation of the standard available refrigerant - circulating water (~20-25°C) - it is impossible to use necessary for condensing high pressure (4-5 ATA), as this boiling temperature such extractants is excessively high (more than 200-250°C) and when it is substantial decomposition of these polar solvents. In addition, required inaccessible heating agents.

According to these sources, when working with wysokosc pasemi the extractants typically use relatively low (1-1,5 ATA) pressure desorbers and is kompremirovannyj debarbieux hydrocarbons. However, the use of compressors associated with their relatively rapid wear and frequent breakage, especially when kompremirovannyj easily polymerizing 1,3-butadiene.

A common disadvantage of the above methods of isolation and purification of 1,3-butadiene are significant (5-8% Rel.) losses due to required dilution of α-acetylene flows in accordance with security requirements. Separating 1,3-butadiene from Butenin conventional rectification is almost impossible and applied industrial schemes involve purification of 1,3-butadiene second extractive distillation. Then cleaned it with a normal rectification respectively from propyne and 1-butyne and metrolina. This leads to the complication of the circuit and increased consumption of power.

We have found technical solutions, allowing for the separation and purification of 1,3-butadiene to exclude compressors significantly reduce the loss of 1,3-butadiene and increase technological and economic efficiency of the processes.

We say:

1. The isolation and purification of 1,3-butadiene from a mixture of predominantly C4-hydrocarbons containing 1,3-butadiene and C4-hydrocarbons, differing from it by the number of unsaturated bonds and/or α-acetylenic protons, including at least the area(s) of extractive distillation with a polar extractant, desorbs and conventional rectification, characterized in that, as specified extractant is used as at least a polar organic solvent with a boiling point above 120°C, hold the Stripping C4-hydrocarbons from the specified extractant from areas of extractive distillation and desorption at high pressure from 3.5 to 6.5 ATA, at least in the lower part and/or in the boiler(s) area(s) of extractive distillation injected hydrocarbon intermediate desorbent with a boiling point of from 27 to 85°C in an amount to provide its content in the cube(s) area(s) desorption of a high pressure of 3 to 30 wt.%. intermediate desorbent then distilled off from the greater part of the extractant in the desorption zone of low pressure at 1.0 to 2.0 ATA, recycle extractant in the upper part of the area (s) of extractive distillation and intermediate desorbent at least the specified(s) point(s) of extractive distillation and 1,3-butadiene is subjected to additional purification from impurities by distillation is possible in the presence of a small amount of extractant.

As an additional means of promoting the most efficient implementation of the method according to claim 1 of the formula, we also declare methods, characterized in that:

- the specified polar solvent is chosen from the group comprising N,N-dimethylformamide, N-organic, N,N-dimethylacetamide, N-formylmorpholine, su is Holan, methoxypropionitrile or mixtures thereof, possibly with water and the specified intermediate desorbent chosen from the group comprising isopentane, n-pentane, pentene, cyclopentane, hexane, hexene, cyclohexane and their mixtures;

- butane(s) and the butenes are separated from 1,3-butadiene in the composition of the distillate of the extractive distillation zone, for the most part, the separating elements which maintain the concentration of the specified extractant from 60 to 85 wt.%;

from the lower part of the desorption(s) area(s) high pressure output side of the steam flow, including at least α-acetylene hydrocarbons, matellan and intermediate desorbent, part of the concentrate stream and return the specified desorption zone and the remainder is removed from the system;

in the upper part of the desorption zone of high pressure serves the additional amount of extractant and maintain his concentration on the majority of the separating elements is not less than 40 wt.%;

- keep the temperature in the cube(s) area (s) of extractive distillation from 90 to 140°C, in the cube(s) area (s) desorption of high pressure from 120 to 170°C and in Cuba distillation intermediate desorbent from the extractant from 120 to 170°C;

purification of 1,3-butadiene from impurities of α-acetylenes C4and metrolina is carried out by distillation in the presence of a small amount of extractant, which is introduced into the top portion of the distillation zone and maintain his concentration on the majority of the separating elements 15 to 40% wt.;

from VAT residue specified zone of rectification in the presence of a small quantity of solvent is distilled off C4-hydrocarbons and the remainder is sent to the indicated zone desorption of high pressure directly or through its boiler;

- prior to the filing of the original hydrocarbon mixture to extractive distillation zone from the above-mentioned mixture is separated by distillation at least propyne and others With3-hydrocarbons;

- prior to the filing of the original hydrocarbon mixture to extractive distillation zone may after rectification at least propene and other C3hydrocarbons in it spend catalytic hydrogenation Butenin and partly of other α-acetylene hydrocarbons to a residual content Butenin from 0.01 to 0.2 wt.%.

Used column separation can contain various mass transfer plates or other mass transfer devices, such as a nozzle.

In addition to filing in the lower part and/or the reboiler zone extractive distillation intermediate desorbent can be served also in the bottom(s) part(s) of desorber(s) high-pressure.

To suppress the undesirable polymerization of 1,3-butadiene in the system of separation in the extractant and/or distillation columns are entered corresponding polymerization inhibitors such as sodium nitrite in the area of extractive rectification phenolic and/or nitrogen compounds in the distillation column. To suppress the hydrolysis of some of the extractants are entered neutralizing agents, and in a system with N,N-dimethylformamide - carbonyl compounds, decomposing formic acid.

To avoid accumulation in the extractant impurity salts, dimers and oligomers of 1,3-butadiene and Butenin etc., a small portion of the extractant (usually 0.5-2% Rel.) displayed on cleaning that is carried out by known methods, for example by distillation and/or azeotropic distillation with water, taking into account the specifics of the extractant, and the purified extractant is returned to the system.

To reduce the amount of power the hot heat flows are used for heating or evaporation cooler threads. For example, in the columns of extractive distillation or rectification with a small input of extractant are installed in places with less high temperature "deaf" (liquid) plates, from which the liquid is supplied for heating (boiling) by the hot stream of the extractant or other fluid, after which the resulting vapor-liquid mixture is returned to the bottom of the column.

The use of the invention is illustrated by the following figures (drawings) 1-3 and examples. These figures and examples do not exhaust all possible options and can be used by other methods subject characteristics specified in the letter of the claims.

According to figure 1 of the original hydrocarbon mixture introduced through line 1, is vaporized and fed to the extractive distillation column 10 through line 2. In the upper part of the column 10 is served by line 3 cooled polar extractant (PE). In the lower part and/or the reboiler of the column 10 line(s) 4 and/or 5 enter the intermediate desorbent(PD) and possible recycling4-hydrocarbons on line 6.

From the column 10 through line 7 output a distillate consisting mainly of butane and butenes. On line 8 from the bottom of column 10 output liquid side stream is passed through a heat exchanger (boiler) and return in a vapor-liquid condition in column 10. From the bottom of column 10 through line 9 output liquid stream which is passed through the boiler and in the steam-liquid state return in column 10. On line 11 of column 10 output VAT stream, consisting mainly of PE, PD, 1,3-butadiene and impurities.

The specified thread 11 served in the desorption zone of high pressure 20. Perhaps in zone 20 also serves on line 12 stream, consisting mainly of the specified OID.

From the top of zone 20 through line 13 output stream, consisting mainly of 1,3-butadiene and impurities. From the zone 20 may deduce the lateral flow line 14, part of it condenses and returns to the zone 20. The rest of containing α-acetylene hydrocarbons and diluent(s), including PD, the lead line 16. From the lower part of the zone 20 through line 17 deduce the liquid flow in the boiler and then into a vapor-liquid state return to the zone 20.

Bottom zone 20 through line 18 output stream consisting of PE and PD. This thread served in the desorption zone of low pressure 30.

From the top of zone 30 output line 19 steam stream 19, consisting mainly of PD. Stream is condensed, a portion of the condensate returned to the area 30, and the other part is carried by line 21 and serves on line 4 in column 10 and/or line 5 in its boiler. Perhaps part of the flow 21 serves on line 12 into the zone 20.

From the bottom of zone 30 through line 22 output stream, which is boiled and return in a vapor-liquid condition in the zone 30. From the cube zone 30 through line 23 output stream is mainly composed of PE. His re-circulate through the heat exchangers and is served by line 3 in column 10.

According to figure 2, column 10 works in a similar way shown in figure 1 and the threads have the same numbers up to the number 11. VAT residue of the column 10 through line 11 serves in the middle or lower part of zone 20, combining the functions of the extractive distillation and desorber high pressure. In the upper part of the zone 20 through line 12 serves stream, consisting mainly of PE. Perhaps in the zone 30 through line 13 serves stream containing mostly DD.

From the top of zone 30 through line 14 deduce the distillate, containing mainly 1,3-butadiene.

From zone 30 by Lin and 15 output steam side stream. Part of it condenses and returns to the zone 30. On line 16 delete a stream containing mainly α-acetylene, matellan and diluent(s). From the bottom of zone 30 through line 17 output stream, which is passed through the boiler and in the steam-liquid state return in the cube zone 30. On line 18 output VAT residue containing mainly PE and PD, and it is sent to the desorption zone of lower pressure 40.

From the zone 40 through line 19 deduce the distillate, containing mostly DD. The specified distillate is fed into the column 10 through line 4 and/or a reboiler line 5. Perhaps part of the distillate is fed to the zone 30 (line 13) and/or boiler.

From the zone 40 through line 21 output liquid flow through the heater in a vapor-liquid state return to the zone 40.

From the zone 40 through line 22 output VAT residue mainly containing possibly partially intermediate desorbent. Part of line 23 serves to heat exchangers and further along the line 3 in column 10, and the other part on line 12 serves in zone 20.

According to figure 3 of the original hydrocarbon mixture in line 1 served in the distillation column 10. From the column 10 through line 2 display a distillate containing at least propyne and thinners. On line 3 output VAT residue containing heavy substance. On line 4 display the main hydrocarbon stream.

Alternatively, the specified thread or frequent is served by lines 5 and 9 in column 30.

As another option, this thread (or part thereof) in line 6 is fed to the zone 20 for the hydrogenation of the α-acetylenes, especially Butenin. On line 7 in zone 20 serves hydrogen. From zone 20 by lines 8, 9 and the heat exchanger (evaporator) of the hydrocarbon stream from the zone 20 is fed to the column 30.

In the upper part of the column 30 through line 11 serves stream, containing mainly PE. In the lower part of the column 30 or/and the boiler is available on line(s) 12 and/or 12' thread(s)that contain(s) predominantly PD. Possibly on the line 13 in column 30 serves part of the distillate from the zone 40.

From the column 30 through line 14 deduce the distillate, containing mainly butane and butenes. From the bottom of column 30 output lines 15 and 16 of the liquid side streams, which is heated in a vapor-liquid state return to the column 30. On line 17 output VAT residue containing mainly PE, PD, 1,3-butadiene and impurities. Its on line 18 serves in the desorption zone of high pressure 40. Possibly in the lower portion of zone 40 serves on line 19 stream containing mostly DD.

From the top of zone 40 through line 21 and is possible on line 22 output stream(s)containing(e) predominantly 1,3-butadiene and impurities: α-acetylene and meillan. Stream 21 is served in a distillation zone 70.

Possibly on line 23 output steam flow, including α-acetylene C4and thinners, served in additional de is orber high pressure 60. From the top of desorber 60 output line(s) 24 or/and 24A thread(s)that contain(s) α-acetylene C4meillan and thinners.

From the lower part of the zone 40 through line 25 output liquid stream containing mainly PE and PD. This stream is combined with the liquid stream from the cube of desorber 60 (line 38)is passed through the heater and a portion of the resulting vapor-liquid flow returns to the zone 40, and its other part served in desorber 60. Bottom zone 40 output liquid stream containing mainly PE and PD, and 26 direct it to the desorption zone of low pressure 50.

Top zone 50 output line 27 steam stream, containing mainly PD, condense it, part of the condensate return to the zone 50, and the remaining amount is distributed into parts, which are served in an area of 30 line(s) 12 and/or 12', in the lower part of the distillation column 70, line 31, and possibly in the lower part or the reboiler zone 40.

From the lower part of the zone 50 through line 28, remove the liquid flow, which is heated in a vapor-liquid state return to the zone 50. From the cube zone 50 through line 29 output stream, containing mainly PE, part of which is along the lines 32 and 11 are directed to the upper part of the column 30, and the other part on the line 33 serves in the upper part of the column 70.

From the top of the column 70 is removed from line 34 distillate containing pure 1,3-butadiene. From the bottom of the column 70 output if the s 35 and 36 liquid flows, which is heated in a vapor-liquid state return in column 70.

From the cube column 70 output line 37 of the liquid stream, which is fed to the column 60.

In all the examples: Fin- the original hydrocarbon mixture F - food in a particular area, D is the distillate(s), B - CBM(e) residue(s), ER - extractive rectification, VD - desorption high pressure LP - low pressure desorption, me - rectification with a small flow of extractant, N is the number of plates, R - reflux number; all concentrations are in wt.%.

Example 1

The process is implemented according to figure 1. Lines 6, 12, 14, 15, 16 are not used. The original mix is a C4-hydrocarbon fraction of pyrolysis. Polar extractant - N,N-dimethylformamide (DMF), intermediate desorbent - called pentane. The concentration of the extractant in the Central zone of the ER - 70% wt.

Characteristics of the main flow and process parameters given in table 1.

Example 2

The process is implemented according to figure 2. The original mix is a4-hydrocarbon fraction of pyrolysis. Polar extractant - N,N-dimethylformamide (DMF), intermediate desorbent - N. mixture of pentane and n-hexane (2:1). The concentration of the polar extractant in the middle part of the column 10-70 wt.%, in the upper part of the zone (below entry 12) 20-60 wt.%.

Characteristics of the main flow and process parameters given in table 2.

Example 3

The process is implemented according to figure 3. The original mix is a C4-hydrocarbon fraction of pyrolysis. In the zone 20 is used, the hydrogenation catalyst Pd on solid media. As the polar solvent used is N-organic 2% wt. water. Intermediate desorbent - isolantes. The concentration of the polar solvent (extractant): in the middle part of the column 30 is 70 wt.%, in the middle part of the column 70 is 25-27% wt.

Characteristics of the main flow and process parameters given in table 3.

Table 1 for example 1
Components (% wt.) and parametersFinLin. 1The extras, rectif. (No. 10)VD-desorption (zone 20)ND-desorption (zone 30)
D Lin. 7B Lin. 11D Lin. 13B Lin. 18D Lin. 21B Lin. 23
C3-hydrocarbons (incl. proein)0,7 (0,2)0,9 (~)- 0,03 ~ 0,45---
butane9,517,2-----
isobutan23,442,4-----
1-butadiene12,422,5----
2-butenes9,416,50,05 CIS-2-b0,61---
1,3-butadiene43,00,57,595,36---
meillan0,2-0,030,45---
1-butyn0,2-0,030,45---
Butenin0,7-0,141,56---
With5-coal. in Fin0,5-0,121,12---
desorbent PD--6,90-7,595,00,6
the extractant-- 85,20-92,55,099,4
Σ kg/hour100,055,2569,244,8524,4to 38.3486,1
N (practical.)1505020-30
E/F., wt.a 4.83--
Pressure top, ATA4.0 to 4.54.0 to 4.51,0-1,1
Temperature.(°C): top~40~40~40
cube115-120 160150-160

Table 2 : example 2
Components (% wt.) and parametersFinLin. 1ER-1Zone 20 (ER -2)VD-desorption (zone 30)ND-desorption (No. 40)
D Lin. 7B Lin. 11D Lin. 14Side. selection, Lin. 16B Lin. 18D Lin. 19 (threads 4/13)B Lin. 22 (threads /12)
C3-hydrocarbons (incl. propyne)0,7 (0,2)0,9 (~)~ 0.030.0050,2-
butane9,517,2----
isobutan23.442,4----
1-butene12,422,5----
2-butenes9,416,50,05 IPR-2-bn0,05--
1,3-butadiene43,00,57,599,07the 9.7-
meillan0,2-0,030,027,3-
1-butyn0,2-0,030.003the 9.7-
Butenin0,7-0,140,00234,1-
C5-fragile. in Fin0,5-0,1219,50,020,1-
desorbent PD--6,90-19,5the 7.4395,00,6
the extractant--85,20-the 92,565,099,4
Σ kg/hour100,055,2569,242,95-2,05628,345,7 (37,9/7,8)582,6 (486/96,6)
N (practical.)15040-4540-4520-30
E/F., wt3,832,18~
Pressure top, ATA4.0 to 4.54.0-4.54.5 to 5.01,0-1,1
Temperature.(°C): top~40~40
cube~115-120160155-160

Table 3 : example 3
Components (% wt.) and parametersFinL. 1Rectification Col. 10Zone 20 o.ER-1 number. 30VD-desorbs. Zone 40ND-desorbs. Area 50VD-des. 3.-60MAE rect. Col. 70
D L. 2B L 3Side. L. 4L. 8D L 14B L. 17D L 21B L. 26D L 27B L. 29D L 24D L 34In L. 37
C3-hydrocarbons (including propyne) 0,7 (0,2)35,0 (10,0)-is 0.00020,0005--0.001----0,001-
butane9,535,015,48,99,116,2--------
isobutan23.415,0-23,923,842,4-------
1-butene 12,410,0-12,613,023,2-------
2-butenes9,4~23,09,4the 10.117,60,050,71---2,00,70,01
1,3-butadiene43.05.015,444,243,70,67,7198,83---38,099,30,25
methyl-all is n 0,27,70,10,08-0,0140,18---14,00,010,09
1-butane0,20,20,07-0,0120,16---14,00,0010,09
Butenin0,70,70,05-0,0090,12---10,00,0020,06
C5-coal. In Fin0,5-a 38.50,05----------
desorbent PD------6,91-9,295,00,622,0-19,85
the extractant------85,30-90,85,099,4--79.65
Σ kg/hour100,02,01,396,796,754,2548,342,5584,553,1*531,4*0,542,179,1
N (practical.)70-8015040-5020-304070-80
E/F., wt.-4,8
Pressure top (ATA)5,0-5,5 4.0 to 4.54.0 to 4.51,0-1.24.0 to 4.54.0 to 4.5
The pace.(°C): top40-4520-
30
40-4540-4535-4540-4540-45
cube~60105-115~160~160~160130-140
* - the relationship thread: 11/p=468/63, para.12(12')/p=63,0/15,7.

1. The isolation and purification of 1,3-butadiene from a mixture of predominantly4-hydrocarbons containing 1,3-butadiene and C4-hydrocarbons, differing from it by the number of unsaturated bonds and/or α-acetylenic protons, including at least the area(s) of extractive distillation with a polar extractant, desorption and customary d is the certification, characterized in that, as specified extractant is used as at least a polar organic solvent with a boiling point above 120°C, hold the Stripping4-hydrocarbons from the specified extractant from areas of extractive distillation and desorption at high pressure from 3.5 to 6.5 ATA, at least in the lower part and/or in the boiler(s) area(s) of extractive distillation injected hydrocarbon intermediate desorbent with a boiling point of from 27 to 85°C in an amount to provide its content in the cube(s) area(s) desorption of a high pressure of 3 to 30 wt.% intermediate desorbent then distilled off from the greater part of the extractant in the desorption zone of low pressure at 1.0 to 2.0 ATA, recycle extractant in the upper part of the area(s) of extractive distillation and intermediate desorbent at least the specified(s) point of extractive distillation and 1,3-butadiene is subjected to additional purification from impurities by distillation is possible in the presence of a small amount of extractant.

2. The method according to claim 1, characterized in that the polar solvent is chosen from the group comprising N,N-dimethylformamide, N-organic, N,N-dimethylacetamide, N-formylmorpholine, sulfolan, methoxypropionitrile or mixtures thereof, possibly with water and the specified intermediate desorbent selected from the group vkluchaya is isopentane, n-pentane, pentene, cyclopentane, hexane, hexene, cyclohexane, and mixtures thereof.

3. The method according to claim 1, characterized in that Bhutan(s) and the butenes are separated from 1,3-butadiene in the composition of the distillate of the extractive distillation zone, for the most part, the separating elements which maintain the concentration of the specified extractant from 60 to 85 wt.%.

4. The method according to claim 1, characterized in that the lower part of the desorption(s) area(s) high pressure output side of the steam flow, including at least α-acetylene hydrocarbons, matellan and intermediate desorbent, part of the concentrate stream and return the specified desorption zone and the remainder is removed from the system.

5. The method according to claim 1, characterized in that the upper part of the desorption zone of high pressure serves the additional amount of extractant and maintain his concentration on the majority of the separating elements is not less than 40 wt.%.

6. The method according to claim 1, characterized in that the support temperature in the cube(s) area (s) of extractive distillation from 90 to 140°C, in the cube(s) area (s) desorption of high pressure from 120 to 170°C. and in Cuba distillation intermediate desorbent from the extractant from 120 to 170°C.

7. The method according to claim 1, characterized in that the purification of 1,3-butadiene from impurities of α-acetylenes With4and metrolina is carried out by distillation in the presence of the scarlet amount of extractant, which is introduced into the upper part of the distillation zone and maintain his concentration on the majority of the separating elements 15 to 40 wt.%.

8. The method according to claim 7, characterized in that the cubic remainder of the zone of rectification in the presence of a small quantity of solvent is distilled off4-hydrocarbons and the remainder is sent to the indicated zone desorption of high pressure directly or through its boiler.

9. The method according to claim 1, characterized in that prior to the filing of the original hydrocarbon mixture to extractive distillation zone from the above-mentioned mixture is separated by distillation at least propyne and others With3-hydrocarbons.

10. The method according to claim 1, characterized in that prior to the filing of the original hydrocarbon mixture to extractive distillation zone may after rectification at least propene and other3-hydrocarbons in it spend catalytic hydrogenation Butenin and partly of other α-acetylene hydrocarbons to a residual content Butenin from 0.01 to 0.2 wt.%.



 

Same patents:

FIELD: petroleum processing and petrochemistry.

SUBSTANCE: catalysate of reforming of long gasoline fractions containing more than 2% benzene is separated by rectification into three fractions: light-boiling fraction containing mainly nonaromatic C4-C6-hydrocarbons and no more than 1%, preferably no more than 0.5%, benzene; high-boiling fraction containing mainly aromatic and nonaromatic hydrocarbons C7 or higher and no more than 1%, preferably no more than 0.5%, benzene; and benzene fraction boiling within a range of 70-95°C and containing no more than 0.1%, preferably no more than 0.02%, toluene and no more than 0.02% nonaromatic hydrocarbons with boiling temperature above 110°C. Benzene fraction is routed into benzene isolation process involving extractive rectification with polar aprotic solvent having ratio of dipole moment to square root of molar volume above 0.3 db/(cm3/g-mole)1/2, preferably above 0.4 db/(cm3/g-mole)1/2, and boiling temperature 150 to 250°C.

EFFECT: improved quality of benzene.

4 dwg, 2 tbl, 5 ex

FIELD: petrochemical processes.

SUBSTANCE: invention relates to chemical processing of petroleum products, notably to the process of producing o-xylene concentrate, high-octane gasoline component with improved environmental characteristics, commercial benzene and toluene from petroleum and gas-condensate feedstock. According to invention, gasoline reforming catalysate is subjected to fractionation on two rectification columns. Top product of the first column is benzene-toluene fraction with output ensuring potential production of sum of ethylbenzene and m- and p-xylenes in the top product equal to 10-45%. Side product is toluene-xylene fraction with output ensuring potential production of toluene in the side product equal to 5-30%. Bottom residue is fraction of aromatic hydrocarbons C9 and higher. Side product bleeding point in the column is selected such that temperature difference between column bottom and this point were within a range of 30-70°C. Benzene-toluene fraction from the first column top is fed into the second rectification column operated under excess pressure 2-5 kg/cm2. Top product of the second column is pre-benzene fraction with output ensuring potential production of non-aromatic C3-C6-hydrocarbons in the top product equal to 65-95%. Side product is benzene concentrate with output ensuring potential production of non-aromatic C7-C8-hydrocarbons in the side product equal to 30-65%. Bottom residue is toluene-xylene fraction. Side product bleeding point is selected such that temperature difference between side bleeding and column top were within a range of 35-75°C. Bottom product of the first column is combined with distillate and bottom residue of the second column thus producing high-octane gasoline component with improved environmental characteristics. Side distillates of the two columns are combined with benzene-toluene reforming catalysate and thus obtained product is consecutively subjected to hydrogenation, extraction with solvent refining agent to form extract, wherefrom commercial benzene, toluene, and o-xylene concentrate are recovered.

EFFECT: enlarged assortment of products, increased production of commercial benzene and toluene meeting State Standard requirements and also high-octane gasoline component with improved environmental characteristics.

2 cl, 15 ex

FIELD: petrochemical industry; production of an aromatic solvent, benzole, toluene and a high-octane component of gasoline.

SUBSTANCE: the invention is pertaining to the field of petrochemical industry, in particular, to production of an aromatic solvent, benzole, toluene and a high-octane component of gasoline with the improved ecological characteristics from gasoline and gas-condensate raw stock. The method provides, that the gasoline reforming catalysate is subjected to the fractionation in a rectifying column. In the top of the column they separate a pre-benzole fraction at the rate, at which the potential withdrawal of the non-aromatic hydrocarbons C3-C6 with it makes 65-95 mass %. With the help of a side withdrawal they extract a benzole-toluene-xylene fraction at rate, at which the potential withdrawal of the aromatic hydrocarbons C9 and higher in the fraction makes 2-20 mass %. As a bottoms product of the column they extract the fraction of aromatic hydrocarbonsС9 and higher. The point for the column side withdrawal chose so, that the temperature difference between this point and the top part of the column is located within the range of 40-80°C. The side-cut distillate of the column is mixed with the catalysate of the benzole-toluene reforming, the produced product is in series subjected to hydrogenation, an extraction with the help of a selective solvent with separation from an extract of a rectified commercial benzole, toluene, an aromatic solvent. The pre-benzole fraction and the fraction of the aromatic hydrocarbons C9 and higher is mixed and in the result produce a high-octane component of gasoline with improved ecological characteristics. The method allows to obtain a high-octane component of gasoline with improved ecological characteristics and also a commercial benzole with a high withdrawal and quality.

EFFECT: the invention ensures production of a high-octane component of gasoline with improved ecological characteristics and a commercial benzole with a high withdrawal and quality.

7 ex

The invention relates to a method of allocating arenes C8mixtures of saturated hydrocarbons, in particular of the xylene fraction catalyzate reforming azeotropic distillation with butanol-2

The invention relates to the field of production of benzene and high-octane mixtures
The invention relates to the field of chemical technology of organic synthesis, in particular to the production of chlorinated products, such as vinyl chloride

The invention relates to the chemical, petrochemical, as well as to the allocation method concentrate benzylideneamino and colorstream components - raw materials for the production of benzene and toluene reforming and primary fraction for the production of environmentally friendly component of motor fuel reforming from a wide gasoline fraction containing saturated hydrocarbons, C2-C5benzene forming limit hydrocarbon, C6, colororange saturated hydrocarbons, C7limit hydrocarbon, C8-C10, aromatic hydrocarbon, C6-C10and other impurities by distillation

The invention relates to the field of chemicals, petrochemicals, and more specifically to a method for selection of high-octane component of motor fuel and benzene from catalization reforming of gasoline fractions

The invention relates to chemical processing of petroleum products, namely the catalytic reforming process for producing high-octane component of motor fuel (reduced VCMT) octane (abbreviated PTS) 95 points and above on the research method (PIM) of the catalysts reforming 91-93 PTS PIM

The invention relates to an improved method of extraction of aromatic hydrocarbons FROM8from catalization reforming of straight-run gasoline fractions containing as impurities paraffin Uglevodorody9and higher olefins, cycloparaffins and cycloolefins hydrocarbons WITH8and above

FIELD: chemistry.

SUBSTANCE: invention relates to a method of producing pure 1-butene from C4 hydrocarbon fractions primarily containing 1-butene, 2-butene, and butane(s) with a 1,3-butadiene and isobutene impurity, involving preparation of a mixture primarily containing 2-butenes via rectification, catalytic isomerisation of 2-butenes into 1-butene and extraction of 1-butene via rectification, characterised by that at least catalysed isomerisation of 1-butene into 2-butene in said fraction is carried out at temperature lower than 120°C, as well as rectification with continuous removal of isobutane, isobutene and 1,3-butadiene in the distillate and obtaining a residual stream primarily containing 2-butene and n-butane, in which rectification conditions are maintained such that concentration of 1,3-butadiene and isobutene with respect to the sum of 2-butene is not higher than standard limits in the desired 1-butene. A large portion of n-butane is separated from the residual stream via extractive rectification with a polar agent and catalysed isomerisation of 2-butenes to 1-butene is carried out at temperature higher than 120°C, while continuously extracting the formed 1-butene via rectification.

EFFECT: high efficiency of the method.

14 cl, 5 ex, 4 tbl, 2 dwg

FIELD: chemistry.

SUBSTANCE: invention relates to a method of separating isopentane-isoamylene-isoprene-containing hydrocarbon fractions or butane-butylene-divinyl hydrocarbon fractions obtained at the first step of two-step dehydrogenation of corresponding paraffin hydrocarbons, involving separation of paraffin-olefin-diene fraction obtained at the first dehydrogenation step through extraction rectification, and is characterised by that a vapour stream is extracted from a desorber via lateral collection, where the said vapour stream contains large amount of diene, and after condensation, said stream is taken for extraction of the diene end product at the second extraction rectification step, and an olefin fraction which does not contain diene is collected from the top of the desorber and taken to the second dehydrogenation step.

EFFECT: use of said method increases output of the end product.

1 cl, 2 ex, 1 dwg

FIELD: chemistry.

SUBSTANCE: invention relates to peptides which originate from an antigen recognised by autoantibodies used for diagnosing rheumatoid arthritis. The peptides are filaggrin molecule fragments which contain modified residues of arginine and having amino acid sequences given in the formula of invention. The invention discloses a method of diagnosing rheumatoid arthritis by detecting autoimmune antibodies using the said peptide(s) through reaction of the latter with the blood serum of patients suffering from rheumatoid arthritis. Presence of autoimmune antibodies in the analysed sample is indicated by presence of peptide complexes formed with the antibody.

EFFECT: disclosed peptide has high specificity and sensitivity.

4 cl, 1 dwg, 3 tbl

FIELD: chemistry.

SUBSTANCE: invention relates to a method of extracting benzene from mixtures with non-aromatic hydrocarbons, simultaneously obtaining distillate through extractive rectification, characterised by that the selective solvent used is in form of mixtures containing 14.7-48.5 wt % sulfolane or N-formylmorpholine and 48.5-83.3 wt % methylpyrrolidone, containing 2-3 wt % water.

EFFECT: use of given method allows for obtaining benzene, toluene and distillate containing not more than 1-1,5 vol. % benzene, which can be used as a component of motor car fuel or as raw material for pyrolysis process.

1 cl, 1 ex, 4 tbl, 2 dwg

FIELD: chemistry.

SUBSTANCE: invention relates to a method of separating alkane and alkene fractions, possibly containing alkadiene impurities, using extraction rectification in the presence of polar extraction agent(s), wherein the basic amount of alkanes comes out in a distillate stream, and the basic amount of alkenes comes out in a strippant stream distilled from the extraction agent. The method is characterised by that before extraction rectification, the larger part of 1-alkene(s) in the alkane and alkene fractions is isomerised and/or hydroisomerised to 2-alkene(s) at temperature not above 100°C in the presence of heterogeneous catalyst(s) with activity during positional isomerisation of alkene, and possibly a small amount of polar substance which does not deactivate the catalyst(s).

EFFECT: more efficient separation of alkane and alkene mixtures through extraction rectification.

11 cl, 13 ex, 1 dwg

FIELD: chemistry.

SUBSTANCE: method includes supply of initial mixture and dimethylsulfoxide (DMSO) as separating agent, taken in ratio 7-7.5:1 to initial mixture, into extraction rectification column (1) efficiency 50 t.t., initial mixture being supplied on 30 t.t., separating agent on 10 t.t. of column (plate numeration from top of column), phlegm number in column constitutes 1.5-2, taking of benzol in distillate and mixture benzol-perfluorobenzol (PFB) - tertiary amyl alcohol (TAA)-DMSO from column (1) cube , supply of mixture PFB-TA-DMSO on 25 t.t. of column of separating agent regeneration (2) with efficiency 50 t.t., phlegm number in column being 1-3, removal separating agent from column cube and its supply to column (1), supply of column (2) distillate, representing aseotropic mixture PFB-TAA, for separation into complex of two columns (3) and (4) with efficiency 35 t.t., with removal from column cubes of TAA and PFB, respectively, aesotropic mixture being supplied on 18 t.t. of column (3), phlegm numbers of columns (3) and (4) being equal 0.5-1.5 and 1-2 respectively, re-cycle of aseotrope PFB-TAA, which is separated in distillate of column (4) into column(3) feeding, ratio of re-cycle of column (4) and feeding of column (3) being (1-1.1):0.66, pressure in columns (1)-(3) is 300 mm of mercury, pressure in column (4) - 760 mm of mercury.

EFFECT: simplification of technology, increase of ecological compatibility of process and quality of obtained products.

1 tbl, 1 dwg, 1 ex

FIELD: chemistry.

SUBSTANCE: described is the method of obtaining unrefined 1, 3-butadiene with the help of extractive distillation from C4-fractions, which contain C4-acetylenes as the secondary components, with the use of a selective solvent. The method is achieved in a column with dividing partitions, which contains in the bottom part an evaporator, in which lengthwise there is a dividing partition, which forms the first zone, the second zone and the underlying combined zone of the column, connected along the upper flow with the extractive washing column. Supply of energy to the column with the dividing partition through the lower evaporator is regulated such that from the column with the dividing partition draw off the lower stream, which contains the solvent, saturated with C4-acetylenes, in which the portion of 1, 3-butadiene is limited with the estimation that the 1, 3-butadiene lost is economically acceptable. In this case the lower stream is submitted into the decontaminator for acetylenes, from which C4-acetylenes are removed and the purified solvent is removed from it from the lower stream.

EFFECT: increase in the periods of the operation of the device between the cleaning cycles.

11 cl, 1 tbl, 1dwg, 1ex

FIELD: chemistry.

SUBSTANCE: method of separation of starting mixture (A) consisting of two or more constituents, by extractive distillation with the selective solvent (S) within dividing wall column (TKW), is proposed. The separation is performed in the dividing wall column (TKW) having a dividing wall aligned in a longitudinal direction (TW) and extending to an upper end of the column and dividing an interior of the column into first region (1), second region (2), and lower combined column region (3). The starting mixture is fed into first region (1), first top stream (B) is taken off from first region (1), and second top stream (C) is taken off from second region (2), with each of the streams having a prescribed specification. The selective solvent (S) is introduced in an upper part of first region (1) and/or in an upper part of second region (2), and flow of solvent (S1) into the first region (1) and/or flow of solvent (S2) into second region (2) are set so that each of the prescribed specifications for top streams (B, C) are met.

EFFECT: invented method of dividing mixtures is more efficient in terms of energy and solvent consumption.

6 cl, 7 dwg, 1 tbl

FIELD: petrochemical processes.

SUBSTANCE: invention relates to a method for continuously separating C4-fraction by extractive distillation using selective solvent on extractive distillation column, which method is characterized by a separation barrier disposed in extractive distillation column in longitudinal direction extending to the very top of the column to form first zone, second zone, and underlying common zone. Butanes (C4H10)-containing top stream is withdrawn from the first zone, butenes (C4H8)-containing top stream is withdrawn from the second zone, and C4H6 stream containing C4-fraction hydrocarbons, which are more soluble in selective solvent than butanes and butenes, is withdrawn from underlying common zone of column.

EFFECT: reduced power consumption and expenses.

15 cl, 2 dwg, 2 ex

FIELD: petrochemical processes.

SUBSTANCE: hydrocarbon mixture obtained by extractive distillation of C4-fraction using selective solvent, which mixture contains those C4-hydrocarbons, which are better soluble in selective solvent than butanes and butenes, is subjected to continuous separation. Mixture is supplied to first distillation column, wherein it is separated into top stream, containing 1,3-butadiene, propine, and, if necessary, other low-boiling components and, if necessary, water, and bottom stream containing 1,3-butadiene, 1,2-butadiene, acetylenes, and, if necessary, other high-boiling components. Proportion of 1,3-butadiene in bottom stream of the first distillation column is controlled in such a way as to be high enough to dilute acetylenes beyond the range wherein acetylenes can spontaneously decompose. Top stream from the first distillation column is passed to second distillation column, wherein it is separated into top stream, containing propine, and, if necessary, other low-boiling components and, if necessary, water, and bottom stream containing pure 1,3-butadiene.

EFFECT: simplified process and reduced power consumption.

4 cl

FIELD: chemistry.

SUBSTANCE: invention relates to a single-step method for gas-phase production of butadiene, involving conversion of ethanol or a mixture ethanol and acetaldehyde in the presence of a catalyst, characterised by that the reaction takes place in the presence of a solid-phase catalyst containing a metal selected from: silver, gold or copper, and a metal oxide selected from magnesium, titanium, zirconium, tantalum or niobium oxide.

EFFECT: method provides high output of butadiene, selectivity of the process and high degree of conversion of material.

6 cl, 23 ex, 1 tbl

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