Method of recovering crude 1,3-butadiene from c4-fraction

FIELD: industrial organic synthesis.

SUBSTANCE: crude 1,3-butadiene is recovered from C4-fraction by extractive distillation using selective solvent on column separated by a partition installed along longitudinal direction of the column to form first and second subzones and underlying common column zone. The column is connected to preswitched flush column. Distillation column operation is controlled by energy supply with the aid of lower evaporator and distribution of a series of theoretical plates within underlying common zone to create bottom stream therefrom consisting of purified solvent.

EFFECT: simplified process technology.

23 cl

 

The present invention relates to a method of allocating crude 1,3-butadiene from C4-fraction by extractive distillation using a selective (selective) solvent.

The allocation of crude 1,3-butadiene from C4-faction is a complex distillation problem because of the small difference in relative volatility of the components4-faction. Therefore, fractionation carried out by extractive distillation, i.e. distillation with the addition of the extractant, which has a boiling point higher than the boiling point of the mixture, which is subjected to fractionation, and increases the difference in relative volatility subjected to separation of components. The use of suitable extractants allows you to fractionate the above With4-fraction by extractive distillation with obtaining fractions of crude 1,3-butadiene, which is subsequently subjected to a further treatment in distillation columns with a stream containing hydrocarbons which are less soluble than 1,3-butadiene, in particular butane and butenes, and a stream containing hydrocarbons, which are much easier soluble than 1,3-butadiene, in particular the butins and possibly 1,2-butadiene.

According to the present invention the crude 1,3-butadiene is a hydrocarbon mixture which is allowed to receive from C 4-faction, of which at least 90 wt.% from the amount of butane and butenes, preferably at least 96 wt.% from the amount of butane and butenes, particularly preferably at least 99 wt.% from the amount of butane and butenes, and yet, at least 90 wt.% With4-acetylenes, preferably at least 96 wt.% With4-acetylenes, especially preferably at least 99 wt.% With4-acetylenes, have been removed. Crude 1,3-butadiene often contains at least 80 wt.%, preferably 90 wt.%, particularly preferably 95 wt.% 1,3-butadiene in the form of the target product, and the remainder is impurity.

On the other hand, used the term "pure 1,3-butadiene" refers to hydrocarbon mixtures containing at least 99 wt.%, preferably of 99.5 wt.%, especially preferably of 99.7 wt.% 1,3-butadiene in the form of the target product, and in which the remainder is impurity.

DE 10105660.5 describes a method that provides a simpler construction of the apparatus in comparison with older technological processes: fractionation With4-faction carried out in a column with a dividing partition, with the partition wall, which extends to the highest point of the column, and extractive wash column, mounted upstream over the column with a dividing partition.

RA is the opening of the above-mentioned application DE 10105660.5 fully incorporated by reference into this patent application.

In the method described in DE 10105660.5, a stream of partially degassed solvent selected from the bottom of the column with a dividing partition, used for extractive distillation. The term "partially degassed solvent" well-known specialist in the field of extractive distillation for separation of 1,3-butadiene and belongs to the selective solvent in which are dissolved components from C4-faction subjected to fractionation, mainly components that have the greatest affinity to selective solvent. These components include, in particular, With4-acetylene, especially ETHYLACETYLENE and vinylacetylene.

However, the stream is only partially degassed solvent cannot be re-returned to the extractive distillation, as otherwise acetylene will accumulate and lead to the product not meeting specifications. For this reason, the bottom stream is taken from the column with a dividing partition, must first be submitted in Gazpromavia column, known for example from DE-A 2724365, which operates at a pressure lower than the pressure in the column, from the lower part of which is taken partially degassed stream before the lower flow again returns to the extractive distillation. In digatal the authorized column flow partially degassed solvent is processed to obtain purified, i.e. completely degassed solvent at the bottom and flow of gaseous hydrocarbons in the upper part of the degassing column, and the last thread again return with a compressor in the bottom area of the extractive distillation column.

In this context, the term "purified solvent or fully degassed solvent" refers to solvents that depleted components from C4-faction to such an extent that is suitable for use as a selective solvent in the process of extractive distillation With4-faction in order to meet the technical requirements for crude 1,3-butadiene and raffinate 1. Key components include4-acetylene, in particular ETHYLACETYLENE and vinylacetylene.

The present invention is to develop a more economical way of separating crude 1,3-butadiene from C4-fraction by extractive distillation and obtaining the purified solvent directly from the bottom of the extractive distillation column.

The set task is solved by the proposed method of extraction of crude 1,3-butadiene from C4-fraction by extractive distillation using a selective solvent in the column with the baffle installed in the longitudinal direction is the column with the formation of the first and second subbands, and the underlying joint zone of the column, and the column is connected with the upstream extractive wash column, due to the fact that columns with baffle set by adjusting its supply through the evaporator and the placement of the number of theoretical plates in the underlying joint zone of the column to ensure receipt of her bottom stream consisting of the pure solvent.

Unexpectedly, it was found that the purified solvent which can be recycled to the extractive distillation can be extracted directly from the bottom of the extractive distillation column without the need for any additional degassing column. To achieve this, it is possible and sufficient to regulate the supply column extractive distillation through the bottom of the evaporator and the number of theoretical plates in the underlying joint area of the extractive distillation column, is made as columns with baffle that creates a business environment that allows to extract the purified solvent from the lower zone of the extractive distillation column.

With4-fraction, which is used as the initial mixture in the proposed method, is a mixture of hydrocarbons having predominantly four atom operadas the molecule. With4-faction receive, for example, in the production of ethylene and/or propylene by thermal cracking of petroleum fractions, such as LPG, light naphtha or gas oil. In addition, With4the fraction obtained when the catalytic dehydrogenation of n-butane and/or n-butene. With4-fractions usually contain butane, n-butene, isobutene, 1,3-butadiene and small amounts of C3- and5-hydrocarbons, as well as the butins, in particular 1-Butin (ETHYLACETYLENE) and Butenin (vinylacetylene). The content of 1,3-butadiene is generally from 10 to 80 wt.%, preferably from 20 to 70 wt.%, in particular from 30 to 60 wt.%, while the content of vinylacetylene and ETHYLACETYLENE usually does not exceed 5 wt.%.

In the case of this separation problem, mainly with the release of 1,3-butadiene from C4-faction possible extractants, i.e. selective solvents for extractive distillation, a particular first, are substances or mixtures, which generally have a boiling point higher than the boiling point of the mixture, is subject to fractionation, and have a greater affinity to conjugated double bonds and triple relations than simple double bonds or single relations, preferably dipolar solvents, particularly preferably dipolar aprotic solvents. In order to avoid to the Rosie equipment preference is given to substances, which are corrosion-resistant or have minor corrosion activity.

Selective solvents suitable for the method of the present invention are, for example, butyrolactone, NITRILES such as acetonitrile, propionitrile, methoxypropionitrile, ketones, such as acetone, furfural, amides, N-alkyl substituted lower aliphatic acids, such as dimethylformamide, diethylformamide, dimethylacetamide, diethylacetamide, N-formylmorpholine, amides, N-alkyl substituted cyclic acids (lactam), such as N-alkylpyridine, in particular N-organic. In General, use the amides of N-alkyl substituted lower aliphatic acids or amides of N-alkyl substituted cyclic acids. Especially favorable extractants are dimethylformamide, acetonitrile, furfural, and in particular, N-organic.

Is also possible to use mixtures of such solvents with one another, for example N-organic with acetonitrile, mixtures of such solvents with co-solvents, such as water and/or tert-butyl esters, for example methyl tert-butyl ether, ethyl tert-butyl ether, propyl tert-butyl ether, n-butyl tert-butyl ether or isobutyl tert-butyl ether.

Particularly suitable extractant is N-organic, herein referred to for brevity as NMP, preferred is compulsory in aqueous solution, in particular containing from 7 to 10 wt.% water, especially preferably containing 8.3 wt.% water.

Extractive distillation is carried out in a column with the separation wall, in which a dividing wall is installed in the longitudinal direction of the column with the formation of the first subband, the second subband and the underlying joint zone, and which is connected with the upstream extractive wash column.

Columns with a dividing partition, as it is known, is used for compound separation, in General, mixtures of at least three components, each of which must be obtained in pure form. They have a separator, i.e. in General a flat metal plate that is installed in the longitudinal direction in the column, which prevents cross-mixing of liquid and gaseous flows in the sub-columns.

For the purposes of the present invention use a column with a dividing partition having a special configuration, whose partition extends to the highest point of the column and, thus, allows to mix the flows of liquid and vapor only in the underlying joint zone of the column. The first and the second subband are separated from one another by a dividing partition.

Extractive wash column is a counter-current leaching number of the nnu.

In a preferred variant of the process

- C4-faction served in the first subzone of the column with a dividing partition, preferably in its Central region,

stream is selected in the upper part of the first sub-columns with baffle send in the extraction leaching column in its upper part,

in the extraction washing column is conducted countercurrent extraction by processing the first part of the stream of selective solvent in the upper part of the extractive wash column,

- components4-fractions, which are less soluble than 1,3-butadiene in the selective solvent, selected in the upper part of the extractive wash column,

- the bottom stream from the extractive wash column recycle in the upper part of the first sub-columns with baffle

- the second part of the stream of selective solvent is fed to the column with a dividing partition in the upper part of the second subband,

- from the second sub-column with a dividing partition selected crude 1,3-butadiene as the main product, and

- from the underlying joint zone of the column with a dividing partition select the bottom stream consisting of the pure solvent, which is recycled in the process.

Thus, it is preferable that4 -fraction, which is subject to fractionation, served in the first subzone of columns with baffle, particularly preferably in its middle part;

the flow from the upper part of the first sub-columns with baffle served in the upstream extractive wash column, in its lower part,

countercurrent extraction is carried out in the extraction washing column by processing the first part of the stream of selective solvent in the upper part of the extractive wash column,

components4-fractions, which are less soluble than 1,3-butadiene in the selective solvent, selected in the upper part of the extractive wash column, particularly preferably condense in the cooler upper part of the extractive wash column and partially return in the form of a return of the product in the extractive wash column, while the remainder is taken in the form of predominantly butane and buchenstrasse by-product, often referred to as raffinate 1.

By feeding the bottom stream extraction leaching columns, i.e. stream containing the selective solvent, 1,3-butadiene, butanes, butenes and components4-fractions, which are less soluble than 1,3-butadiene in the selective solvent, in the upper part of the first sub-column with the separation Perigord is th result of mass transfer between this thread and 4-faction supplied in the form of vapor in the upper part of the first sub-column with a dividing partition can occur countercurrent extraction emitting components, which are less soluble in the selective solvent than 1,3-butadiene in the upper part of the first sub-column with a dividing partition.

At the lower end of the partition to receive the gaseous stream containing 1,3-butadiene together with components4-fractions, which are less soluble in the selective solvent than 1,3-butadiene, in particular With4-acetylene. These components out of the rising gaseous stream fed through a counter-current of the second part stream of selective solvent, which is introduced into the upper part of the second sub-column with a dividing partition. The gaseous product from the top of the second sub-column with a dividing partition assign and preferably condense in the cooler upper part of the column, the flow of the condensed stream from the upper part of the return in the form of a return of the product to the second area of the column with a dividing partition, and the remainder of the condensed stream from the upper part of the take away in the form of crude 1,3-butadiene.

In the underlying joint zone of the column is complete degassing of the solvent, and in the lower h is STI extractive distillation column to receive the purified solvent.

When determining the power provided by the bottom evaporator of the extractive distillation column, which is necessary in this case, the engineer will take into account the stability of the substance or mixture of substances which is used as a selective solvent in this case.

If the temperature of the selective solvent allows the temperature in the lower portion of the extractive distillation column is mainly set high enough to flow of water used for condensation in the upper part of the extractive distillation column.

However, if the temperature of the selective solvent used in this case, insufficient at a temperature, which is necessary for the production of purified solvent in the lower part of the column should be operated at the temperature of the lower part of the column, which, however, valid for the selective solvent and, respectively, for cooling the lower part of the column should be used cooler, which is more expensive than the water flow.

Particularly preferred selective solvent is, as mentioned above, NMP, preferably in aqueous solution, in particular containing from 7 to 10 wt.% water, particularly preferably 8.3 wt.% water.

Eslick selective solvent used NMP, the temperature in the lower portion of the extractive distillation column is preferably set in the range from 170 to 190°S, especially preferably 180°C. the Absolute pressure in the bottom of the second subband of the extractive distillation column, made in the form of columns with baffle respectively set in the range from 1 to 10 bar, preferably from 2 to 5 bar, particularly preferably 3.5 bar.

In principle, there is no need to provide a return by-product containing butanes and butenes, i.e. the raffinate 1, in a separate extraction leaching column, installed upstream of the extraction distillation column. You can also integrate extraction leaching column in the first subzone of columns with baffle used as the extractive distillation column, since it is technically practicable and economically feasible to increase the number of theoretical plates in the first subzone columns with baffle respectively establishing specific boundary conditions for the technological process, in particular the composition of4-faction, subject to fractionation, and technical conditions for the raffinate 1.

Preferred variants of the method according to patent DE-A 10105660.5, described below, can also PR is changing for the method of the present invention.

In a preferred variant of the method, the flow of secondary vapor at the lower end of the partition column is divided by appropriate regulating means so that the portion of the flow directed to the first subzone of columns with baffle is greater than the part of the flow directed to the second subzone of the column with a dividing partition. Regulation division of secondary vapor stream at the lower end of the dividing partition allows to provide a simple and reliable manner the necessary technical requirements to the stream of crude 1,3-butadiene selected in the upper part of the second sub-column with a dividing partition.

This uneven distribution of secondary vapor stream at the lower end of the dividing partition is particularly preferably achieved by a dividing partition, installed asymmetrically so that the second subband is smaller than the first subband of the column with a dividing partition.

The partition wall is particularly preferably set asymmetrically in such a way that the ratio of cross-sections of the first subband and a second sub-zone is in the range from 8:1 to 1.5:1, in particular of 2.3:1.

Alternatively, or in addition to the asymmetrical arrangement of dividing the partitions the stream of secondary vapor at the lower end of the partition can be divided in the desired ratio between the two sub-columns with a dividing partition with additional regulatory tools, such as butterfly valves or guides partitions.

Other additional or alternative regulatory tool to separate the flow of secondary vapor at the lower end of the dividing partition is the placement of the power supply heat sink fridge in the upper part of the second sub-column with a dividing partition.

In a preferred variant of the method the pressure on the upper end of both subbands columns with baffle can be adjusted separately. This allows you to provide the necessary technical requirements for crude 1,3-butadiene.

Pressure in the upper part of both subbands columns with baffle preferably installed through branching control. The term "branching control" applies in a known manner to the arrangement in which the outlet of the pressure regulator is connected to the inert gas line and vent line. The adjustment range of the pressure regulator valves are distributed in such a way that simultaneously fires only one valve, i.e. either flowing inert gas, or is ventilation. This allows you to minimize the amount of inert gas and product losses associated with the flow of exhaust air.

In addition or alternatively to Rassvet is laudamus control you can adjust each of the pressures in the upper part of both sub-zones of the column with a dividing partition using the power supply heat sink coolers in the upper part of the second sub-columns with baffle and the upper part of the extractive wash column.

In a preferred variant of the method the pressure in the upper part of the second sub-column with a dividing wall is positioned so that it is greater than the pressure in the first zone of the column with the separation wall, in particular 1-100 mbar, particularly preferably about 1-30 mbar. Such measures provide an opportunity to dispense with fixed welded or expensive tightly compacted dividers and use cheaper removable dividing wall. In the result, the pressure drop from the second to the first sub-columns with baffle leakage of liquid or gaseous flow can only occur in this direction, so it is not critical for the purity of the target crude 1,3-butadiene selected in the upper part of the second subband.

The content of heat in the lower flow of the pure solvent can mainly be used in the method using heat integration, in particular, by removing the liquid or part of the fluid flow from the underlying joint zone of the column with a dividing partition in one or more places, heating and/or evaporation of this fluid by indirect heat exchange with a hot bottom flux is the first of the extractive column distillation and returning it in the underlying compliant zone of the column.

Theoretical plate from which the selected liquid or part of a fluid flow, preferably chosen so as to minimize the total energy demand of the column extractive distillation.

In addition or alternatively, the enthalpy of the lower flow of the pure solvent can also be used for indirect heat exchange with C4-fraction fed to the extractive distillation column.

Removal With4-acetylenes, in particular ETHYLACETYLENE and vinylacetylene, from the technological process, preference is given to selection of lateral flow from the underlying joint zone of the column with baffle flow into the wash column in which the side stream is washed with water, selection of the upper stream of the wash column and condensing it partially or totally, preferably partially, the production part of the condensate and recycling of the residue in the wash column and selecting the bottom stream from the wash column and return it to its underlying joint zone of the column.

Thus, the invention provides a method of separation of crude 1,3-butadiene from C4-fraction by extractive distillation, which, compared with known methods makes it possible to recover the purified solvent, which preferably returns in technology the systematic process directly from the bottom of the extractive distillation column. In the non-use of the degassing column, which hitherto used for these purposes, and the appropriate equipment, including heat exchangers and pumps, but mainly of the compressor discharge flow of the hydrocarbon re-fed into the extractive distillation column, capital costs are lower than for known methods. The ability to do without the compressor, which is incomparably the greatest energy consumer in the method of the prior art, is particularly advantageous. As a result, the ability to do without compressor electricity consumption in the method of the present invention is reduced by about half compared with the method of the prior art.

Implementation of the proposed method is illustrated below with reference to the attached drawing showing a block diagram of an installation for implementing the method.

In the column with the separation wall TC, with a separator T, which is installed in the longitudinal direction of the column and divides the column on the first subzone And including 30 theoretical plates, the second subzone, including 30 theoretical plates, and the underlying joint area, which includes 10 theoretical plates, line 1, in its first subzone And serves to 30 t/h4-faction SOS is ava wt.%: 41,36 1,3-butadiene, 0,17 1,2-butadiene, 27,93 ISO-butene, 14,11 n-butene, of 5.82 n-butane, 1.97 isobutane, 4,79 TRANS-butene-2-, 3,2 CIS-butene-2, 0.51 vinylacetylene, 0,12 butyne-1. In addition, With4-fraction contains another 100 hours/million propene, 400 hours/million PROPADIENE, 800 hours/million propina and 0,002 h/mn5-hydrocarbons. The temperature in the first subzone And is 37°and the pressure of 5.05 bar. Taken from the top of the subband And line 2 in the amount of 264,47 t/h flow composition, wt.%: 49,42 1,3-butadiene, 24,53 ISO-butene, 11,30 n-butene, 3,56 n-butane, 1.17 isobutane, 4,96 TRANS-butene, 4,06 CIS-butene-2. In addition, the flow line 2 contains another 1 h/million vinylacetylene, 10 hours/million butyne-1, 55 hours/million 1,2-butadiene, 60 hours/million propene, 472 hours/million PROPADIENE, 198 hours/million propina, 3648 h/mn5-hydrocarbons, 3908 hours/million water and 1286 hours/million N-methylpyrrolidone. This stream has a temperature of 62.3°and the pressure of 4.9 bar, direct in the lower part located upstream extractive wash column K, with 19 of theoretical plates. In the upper part of the extractive wash column K on line 3 in the number of 248 g/h serves parts taken from the columns of TC as a bottom stream of selective solvent composition, wt.%: 91,7 N-methylpyrrolidone, 8,3 water having a temperature of 38°and the pressure of 4.8 bar. This stream is taken from the column TC selective solvent contains another 29 PM/ml of the d vinylacetylene and 13 o'clock/bn 5-hydrocarbons. In the countercurrent extraction from the upper part of column K on line 4 divert the flow, which condense in connected to the upper part of the extractive wash column K the refrigerator and part of the resulting condensate line 5 recycle to the extraction leaching column K, and the remainder of the condensate composition, wt.%: 0,10 13-butadiene, 48,47 ISO-butene, 24,28 n-butene, 10,06 n-butane, 3.40 isobutane, compared to 8.26 TRANS-butene, to 5.21 CIS-butene-2 and 0.09 water, is removed from the process in the amount of 16,95 t/H. the stream having a temperature 42,9°and 173 g of propene, the pressure of 4.7 bar also contains 173 hours/million propane, 692 hours/million PROPADIENE, 62 am/bn propina and 431 h/bn N-methylpyrrolidone.

In addition, in the countercurrent extraction in column K receive the lower stream of selective solvent, which is on line 7 serves in the upper part of the column TC. The second part is taken from the columns of TC as a bottom stream of selective solvent of the above composition on line 8 serves in the number 59,53 g/h in the second subzone In the column of the LC.

From the second subband In the on line 9 select the upper stream, which, after condensation is divided into two parts, of which one part of the condensate line 10 return in the second subzone In the column TC, and the second part of the condensate, representing a crude 1,3-butadiene, in the amount of 12,31 t/h select p is line 11. This condensate composition, wt.%: 98,87 1,3-butadiene, 0,18 1,2-butadiene, 0,44 CIS-butene-2, of € 0.195 propina and 0.15 water has a temperature of 30°and the pressure of 3.2 bar. In addition, the condensate still contains 337 PM/billion PROPADIENE, 521 h/bn n-butene, 298 h/bn ISO-butene, 271 h/bn TRANS-butene-2, 895 h/bn5hydrocarbons (30 hours/million butyne-1, and 3 hours/million N-methylpyrrolidone.

Of the following joint areas With columns TC on line 12 selected lateral flow, which in the wash column's washed supplied through line 13 water. On line 14 of the wash column's selected stream, which, after condensation is divided into two parts, one of which on line 15 back to the leaching column S, and the other part with content4-acetylenes in line 16 is removed from the process.

The resulting wash water bottom stream in line 17 recycle in the joint area With the columns of the TC. Taken from the bottom of the column TC thread cleaned selective solvent in line 18 is used for heat exchange with a liquid stream taken along the line 19 from the underlying joint area With columns TC, which after heating his return in the underlying joint area with columns TC line 20. As shown in the drawing, the enthalpy of purified selective solvent can also be used mainly for preheating4-fra is tion, supplied through line 1 in column TC. Through CBM evaporator column TC supply energy in 11491 kW.

1. Method of extraction of crude 1,3-butadiene from C4-fraction by extractive distillation using a selective solvent in the column with the baffle installed in the longitudinal direction of the column with the formation of the first and second sub-zone and the underlying joint zone of the column, and the column is connected with the upstream wash column, characterized in that the column is adjusted by regulation of its energy supply through the bottom of the evaporator and the placement of the number of theoretical plates in the underlying joint zone of the column to ensure receipt of her bottom stream consisting of the pure solvent.

2. The method according to claim 1, characterized in that from the underlying joint zone of the column at one or more points are selected liquid or part of a stream of fluid, which is heated and/or vaporized by indirect heat exchange with the bottom stream from the column with a dividing partition and return to the underlying joint zone of the column with a dividing partition.

3. The method according to claim 2, characterized in that the liquid or part of the liquid stream is withdrawn from the underlying joint zone of the column with a theoretical plate, chosen so that the needs of the awn in energy pillars with a dividing partition was minimized.

4. The method according to claim 1, characterized in that the energy part of the bottom stream from the column with a dividing wall used for indirect heat exchange with subjected to rectification With4-fraction, which is fed to the column with a dividing partition.

5. The method according to one of claims 1 to 4, characterized in that the extraction leaching column is structurally combined with the first pajonas columns with a dividing partition by installing a correspondingly larger number of theoretical plates in the first subzone of the column with a dividing partition.

6. The method according to one of claims 1 to 4, characterized in that from the underlying joint zone of the column with the separation wall pick a side stream, which serves to wash the column, which hold washing water from the washing column select upper stream, which condense completely or, preferably, partially in the refrigerator in the upper part of the column, a portion of the resulting condensate return leaching column and the remainder is withdrawn from the process, and the bottom stream from the wash column serves in the underlying joint zone of the column with a dividing partition.

7. The method according to claim 5, characterized in that from the underlying joint zone of the column with the separation wall pick a side stream, which serves to wash the column, where p is avodat washing water, from the wash column select upper stream, which condense completely or, preferably, partially in the refrigerator in the upper part of the column, part of the condensate is returned to the wash column and the remainder is withdrawn from the process, and the bottom stream from the wash column serves in the underlying joint zone of the column with a dividing partition.

8. The method according to one of claims 1 to 4, characterized in that the process is as follows:

With4-faction served in the first subzone of the column with a dividing partition, preferably in its Central region,

the stream selected in the upper part of the first sub-columns with baffle sent to the extractive wash column, in its lower part,

in the extraction washing column is conducted countercurrent extraction by processing the first part of the stream of selective solvent in the upper part of the extractive wash column,

components4-fractions, which are less soluble than 1,3-butadiene in the selective solvent, selected in the upper part of the extractive wash column,

the bottom stream from the extractive wash column recycle in the upper part of the first sub-columns with baffle

the second part of the stream of selective solvent is fed into colonnus baffle in the upper part of the second subband,

from the second sub-column with a dividing partition selected crude 1,3-butadiene as the head product and

the underlying joint zone of the column with a dividing partition select the bottom stream consisting of the pure solvent, which is recycled in the process.

9. The method according to claim 5, characterized in that the process is as follows:

With4-faction served in the first subzone of the column with a dividing partition, preferably in its Central region,

the stream selected in the upper part of the first sub-columns with baffle send in the extraction leaching column in its upper part,

in the extraction washing column is conducted countercurrent extraction by processing the first part of the stream of selective solvent in the upper part of the extractive wash column,

components4-fractions, which are less soluble than 1,3-butadiene in the selective solvent, selected in the upper part of the extractive wash column,

the bottom stream from the extractive wash column recycle in the upper part of the first sub-columns with baffle

the second part of the stream of selective solvent is fed to the column with a dividing partition in the upper part vtoro the subband,

from the second sub-column with a dividing partition selected crude 1,3-butadiene as the head product and

from the underlying joint zone of the column with a dividing partition select the bottom stream consisting of the pure solvent, which is recycled in the process.

10. The method according to claim 6, characterized in that the process is as follows:

With4-faction served in the first subzone of the column with a dividing partition, preferably in its Central region,

the stream selected in the upper part of the first sub-columns with baffle send in the extraction leaching column, in its lower part,

in the extraction washing column is conducted countercurrent extraction by processing the first part of the stream of selective solvent in the upper part of the extractive wash column,

components4-fractions, which are less soluble than 1,3-butadiene in the selective solvent, selected in the upper part of the extractive wash column,

the bottom stream from the extractive wash column recycle in the upper part of the first sub-columns with baffle

the second part of the stream of selective solvent is fed to the column with a dividing partition in the upper part of W is Roy subband,

from the second sub-column with a dividing partition selected crude 1,3-butadiene as the head product and

from the underlying joint zone of the column with a dividing partition select the bottom stream consisting of the pure solvent, which is recycled in the process.

11. The method according to claim 7, characterized in that the process is as follows:

With4-faction served in the first subzone of the column with a dividing partition, preferably in its Central region,

the stream selected in the upper part of the first sub-columns with baffle send in the extraction leaching column in its upper part,

in the extraction washing column is conducted countercurrent extraction by processing the first part of the stream of selective solvent in the upper part of the extractive wash column,

components4-fractions, which are less soluble than 1,3-butadiene in the selective solvent, selected in the upper part of the extractive wash column,

the bottom stream from the extractive wash column recycle in the upper part of the first sub-columns with baffle

the second part of the stream of selective solvent is fed to the column with a baffle at the top of the hour is ü the second subband,

from the second sub-column with a dividing partition selected crude 1,3-butadiene as the head product and

from the underlying joint zone of the column with a dividing partition select the bottom stream consisting of the pure solvent, which is recycled in the process.

12. The method according to one of claims 1 to 4, characterized in that as the selective solvent used is N-an organic, preferably, in aqueous solution, in particular, with a water content of from 7 to 10 wt.%, particularly preferably, the water content of 8.3 wt.%.

13. The method according to claim 5, characterized in that as the selective solvent used is N-an organic, preferably, in aqueous solution, in particular, with a water content of from 7 to 10 wt.%, particularly preferably, the water content of 8.3 wt.%.

14. The method according to claim 6, characterized in that as the selective solvent used is N-an organic, preferably, in aqueous solution, in particular, with a water content of from 7 to 10 wt.%, particularly preferably, the water content of 8.3 wt.%.

15. The method according to one of claims 7, 9-11, characterized in that as the selective solvent used is N-an organic, preferably, in aqueous solution, in particular, with a water content of from 7 to 10 wt.%, particularly preferably, the water content of 8.3 wt.%.

16 the Method of claim 8, characterized in that as the selective solvent used is N-an organic, preferably, in aqueous solution, in particular, with a water content of from 7 to 10 wt.%, particularly preferably, the water content of 8.3 wt.%.

17. The method according to one of claims 1 to 4, characterized in that the temperature in the lower part of the column with a dividing partition support in the range of from 170 to 190°C, preferably 180°and the absolute pressure in the upper part of the second sub-columns with baffle regulate in the range from 1 to 10 bar, preferably from 2 to 5 bar, particularly preferably 3.5 bar.

18. The method according to claim 5, characterized in that the temperature in the lower part of the column with a dividing partition support in the range of from 170 to 190°C, preferably 180°and the absolute pressure in the upper part of the second sub-columns with baffle regulate in the range from 1 to 10 bar, preferably from 2 to 5 bar, particularly preferably 3.5 bar.

19. The method according to claim 6, characterized in that the temperature in the lower part of the column with a dividing partition support in the range of from 170 to 190°C, preferably 180°and the absolute pressure in the upper part of the second sub-columns with baffle regulate in the range from 1 to 10 bar, preferably from 2 to 5 bar, the person who but preferably 3.5 bar.

20. The method according to one of claims 7, 9-11, 13, 14, or 16, characterized in that the temperature in the lower part of the column with a dividing partition support in the range of from 170 to 190°C, preferably 180°and the absolute pressure in the upper part of the second sub-columns with baffle regulate in the range from 1 to 10 bar, preferably from 2 to 5 bar, particularly preferably 3.5 bar.

21. The method according to claim 8, characterized in that the temperature in the lower part of the column with a dividing partition support in the range of from 170 to 190°C, preferably 180°and the absolute pressure in the upper part of the second sub-columns with baffle regulate in the range from 1 to 10 bar, preferably from 2 to 5 bar, particularly preferably 3.5 bar.

22. The method according to item 12, characterized in that the temperature in the lower part of the column with a dividing partition support in the range of from 170 to 190°C, preferably 180°and the absolute pressure in the upper part of the second sub-columns with baffle regulate in the range from 1 to 10 bar, preferably from 2 to 5 bar, particularly preferably 3.5 bar.

23. The method according to item 15, wherein the temperature in the lower part of the column with a dividing partition support in the range of from 170 to 190°C, preferably 180°and absolutely the e pressure in the upper part of the second sub-columns with baffle regulate in the range from 1 to 10 bar, preferably, from 2 to 5 bar, particularly preferably 3.5 bar.



 

Same patents:

FIELD: petrochemical processes.

SUBSTANCE: invention provides a process flow rate comprising at least (i) zone of extractive rectification in presence of polar extractant to produce distillate mainly containing butanes and butane(s); (ii) desorption zone wherein desorption of extractant gives stream containing mainly 1,3-butadiene and. as impurities, at least 2-butene(s) and acetylene hydrocarbons; and (iii) optionally rectification zone for mainly 1,3-butadiene-containing stream. In the latter, α-acetylene hydrocarbons are subjected to liquid-phase selective hydrogenation with hydrogen or hydrogen-containing mixture in presence of solid catalyst containing metal(s) exhibiting high activity in hydrogenation process, preferably non-precious metal(s) on solid support. Temperature is maintained within a range 5 to 75°C at contact time ensuring hydrogenation of no more then 6%, preferably no more than 2% of butadiene present. After hydrogenation, 1,3-butadiene is optionally additionally separated from impurities via rectification.

EFFECT: simplified process.

13 cl, 3 dwg, 2 tbl, 10 ex

FIELD: petrochemical processes.

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EFFECT: reduced loss of extractant with distillate.

6 cl, 3 dwg, 6 tbl, 6 ex

FIELD: petroleum processing and petrochemistry.

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EFFECT: improved quality of benzene.

4 dwg, 2 tbl, 5 ex

FIELD: petroleum industry.

SUBSTANCE: process in carried out in column having divider arranging in longitudinal direction to form the first section, the second one and the third bottom joint section, wherein extractive scrubber is includes before divider.

EFFECT: simplified technology.

16 cl, 3 dwg

FIELD: petrochemical processes.

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EFFECT: increased separation efficiency.

3 ex

FIELD: petroleum processing and petrochemistry.

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EFFECT: reduced power consumption.

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FIELD: petrochemical processes.

SUBSTANCE: invention provides a process flow rate comprising at least (i) zone of extractive rectification in presence of polar extractant to produce distillate mainly containing butanes and butane(s); (ii) desorption zone wherein desorption of extractant gives stream containing mainly 1,3-butadiene and. as impurities, at least 2-butene(s) and acetylene hydrocarbons; and (iii) optionally rectification zone for mainly 1,3-butadiene-containing stream. In the latter, α-acetylene hydrocarbons are subjected to liquid-phase selective hydrogenation with hydrogen or hydrogen-containing mixture in presence of solid catalyst containing metal(s) exhibiting high activity in hydrogenation process, preferably non-precious metal(s) on solid support. Temperature is maintained within a range 5 to 75°C at contact time ensuring hydrogenation of no more then 6%, preferably no more than 2% of butadiene present. After hydrogenation, 1,3-butadiene is optionally additionally separated from impurities via rectification.

EFFECT: simplified process.

13 cl, 3 dwg, 2 tbl, 10 ex

FIELD: petroleum industry.

SUBSTANCE: process in carried out in column having divider arranging in longitudinal direction to form the first section, the second one and the third bottom joint section, wherein extractive scrubber is includes before divider.

EFFECT: simplified technology.

16 cl, 3 dwg

FIELD: organic chemistry, chemical technology.

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EFFECT: improved method for treatment.

5 cl

FIELD: petrochemical processes.

SUBSTANCE: 1,3-butadiene is obtained via catalytic dehydrogenation of n-butylenes at 580-640°C and essentially atmospheric pressure while diluting butylenes with water steam at molar ratio 1:(10-12) and supplying butylenes at space velocity 500-750 h-1. Catalyst is composed of, wt %: K2O 10-20, rare-earth elements (on conversion to CeO2) 2-6, CaO and/or MgO 5-10. MoO3 0.5-5, Co2O3 0.01-0.1, V2O5 0.01-0.1, and F2O3 the balance. Once steady condition is attained, dehydrogenation is carried out continuously during all service period of catalyst.

EFFECT: increased yield of 1,3-butadiene and process efficiency.

2 ex

FIELD: catalysts of selective hydrogenation of alkynes of C4 fractions.

SUBSTANCE: proposed catalyst contains 1-30 mass-% of copper used as first active component, 0.001-5 mass-% of palladium used as second active component, at least 0.001-6 mass-% of one metal selected from Al, Pt, Pb, Mn, Co, Ni, Cr, Bi, Zr and Mo as co-catalyst; the remainder being one carrier selected from aluminum oxide, silicon dioxide and titanium oxide. Method of production of catalyst includes impregnation of carrier calcined preliminarily with solutions of active components depending on their content in catalyst. Alkynes are removed from C4 fractions enriched with alkynes by means of selective hydrogenation with the use of said catalyst.

EFFECT: enhanced selectivity and stability of catalyst.

31 cl, 2 tbl, 13 ex

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 field of polymers butadienestyrene

The invention relates to the field of production of 1,3-butadiene and high-octane products

The invention relates to the production of butadiene-1,3 single-stage vacuum dehydrogenation of n-butane

The invention relates to the petrochemical industry, namely to obtain butadiene by extracting gas from the contact dehydrogenation of butane-butyl mixtures

FIELD: catalysts of selective hydrogenation of alkynes of C4 fractions.

SUBSTANCE: proposed catalyst contains 1-30 mass-% of copper used as first active component, 0.001-5 mass-% of palladium used as second active component, at least 0.001-6 mass-% of one metal selected from Al, Pt, Pb, Mn, Co, Ni, Cr, Bi, Zr and Mo as co-catalyst; the remainder being one carrier selected from aluminum oxide, silicon dioxide and titanium oxide. Method of production of catalyst includes impregnation of carrier calcined preliminarily with solutions of active components depending on their content in catalyst. Alkynes are removed from C4 fractions enriched with alkynes by means of selective hydrogenation with the use of said catalyst.

EFFECT: enhanced selectivity and stability of catalyst.

31 cl, 2 tbl, 13 ex

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