US3597331A - Process for the recovery of adiponitrile from an electrolytic hydrodimerization by directly distilling the catholyte emulsion - Google Patents

Process for the recovery of adiponitrile from an electrolytic hydrodimerization by directly distilling the catholyte emulsion Download PDF

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Publication number
US3597331A
US3597331A US681203A US3597331DA US3597331A US 3597331 A US3597331 A US 3597331A US 681203 A US681203 A US 681203A US 3597331D A US3597331D A US 3597331DA US 3597331 A US3597331 A US 3597331A
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adiponitrile
acrylonitrile
catholyte
oil phase
phase
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Shinsaku Ogawa
Shoichiro Kumazaki
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Asahi Kasei Corp
Asahi Chemical Industry Co Ltd
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Asahi Chemical Industry Co Ltd
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    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C255/00—Carboxylic acid nitriles
    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25B—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES FOR THE PRODUCTION OF COMPOUNDS OR NON-METALS; APPARATUS THEREFOR
    • C25B3/00—Electrolytic production of organic compounds
    • C25B3/20—Processes
    • C25B3/29—Coupling reactions
    • C25B3/295—Coupling reactions hydrodimerisation

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  • the catholyte emulsion may be directly subjected to the distillation treatment or may rst be separated into an oil phase and aqueous phase with the separated oil phase and a portion of the aqueous phase distilled together.
  • the adiponitrile is preferably recovered from the oil phase by distilling off the lower boiling components, and most preferably subjected to an aqueous extraction to remove supporting electrolyte salt prior to this distillation.
  • the adiponitrile may be further purified utilizing a rectifying tower with the bottoms from this tower being recycled through a stripper back to the distillation ot the lower boiling components.
  • the distillate from the initial distillation of the oil phase and aqueous phase mixture may be recycled directly or after further treatment including, for example, a propionitrile rectification or such rectification followed by phase separation by cooling.
  • This invention relates to a process for separating and purifying adiponitrile from a catholyte in the production of adiponitrile by the electrolytic hydrodimerization of acrylonitrile.
  • adiponitrile may be obtained by the electrolytic hydrodimerization of acrylonitrile as disclosed in US. Pats. No. 3,193,480 and 3,193,481. Moreover, a process for separting adiponitrile from the catholyte in such processes is described in U.S. Pat, No. 3,193,477 and Dutch Pat. No. 6505391.
  • the catholyte in the electrolytic hydrodimerization of acrylonitrile consists of propionitrile, adiponitrile, ethylene cyanohydrin, biscyanoethyl ether, acrylonitrile oligomers (mainly 2-cyanoethyl adiponitrile, and the like), which are formed in the electrolysis, water, acrylonitrile, supporting electrolyte salt and other additives.
  • the electrolysis cell used in the hydrodimerization of acrylonitrile is preferably partitioned by a membrane separating the catholyte from the anolyte,
  • a membrane separating the catholyte from the anolyte
  • the amount of water transferred is quite considerable, and for example, assuming that the conversion of acrylonitrile to adiponitrile is 100%, the yield of adiponitrile is 54 Ig./ Faraday, whereas the amount of water transferred is as much as l050 ⁇ g./ Faraday.
  • the oil phase obtained in the above-mentioned rst step contains a large amount of the supporting electrolyte. For this reason it has been considered necessary to remove the supporting electrolyte from the oil phase by an extraction with, for example, water as a second step. It has been further considered necessary to separate acrylonitrile and propionitrile from the oil phase now free from the supporting electrolyte lby way of a distillation as a third stage.
  • application 642,321 utilizes a catholyte maintained in the state of an emulsion consisting of an oil phase mainly comprising adiponitrile and acrylonitrile and a continuous aqueous phase mainly comprising water and a supporting electrolyte salt with the concentration of the supporting electrolyte salt being less than 30% and with a low concentration of acrylonitrile in both oil and aqueous phases.
  • an electrolyte capable of increasing the solubility of acrylonitrile in the catholyte is not required.
  • the adiponitrile is recovered from the catholyte emulsion used in the electrolytic hydrodimerization of acrylonitrile which emulsion contains an oil phase, a continuous aqueous phase, and a supporting electrolyte salt by distilling a mixture of the oil phase and the aqueous phase obtained from the emulsion to thereby distill off acrylonitrile and water followed by separating the remaining distillation bottom into an oil phase and aqueous phase and recovering adiponitrile from the separated oil phase.
  • the catholyte emulsion may be directly subjected to the distillation, or may initially be first separated into an oil phase and aqueous phase with the separated oil phase and a portion of the aqueous phase distilled together as a mixture.
  • the process in accordance with the invention is applicable for the treatment of any of the catholyte emulsions which may be used in the electrolytic hydrodimerization of acrylonitrile and which contain an oil phase, a continuous aqueous phase, and a supporting electrolyte salt.
  • These emulsions by their very nature and with respect to the hydrodimerization process in which they are used, as described in copending application Ser. No. 642,321, generally have a limited solubility of acrylonitrile and adiponitrile in the aqueous phase of the emulsion, and generally do not contain a material which greatly increases the solubility of the acrylonitrile and adiponitrile in the aqueous phase.
  • catholytes generally contain sulfates or halides as the supporting electrolyte salt.
  • the catholytes preferably have the composition as described in copending application Ser. No. 642,321, and the entire disclosure thereof is incorporated herein by reference.
  • the rectifying tower used for distilling the oil and aqueous phases together may be referred to as acrylonitrile rectifying tower for convenience hereinafter.
  • the liquid distilled in this tower mainly consists of acrylonitrile, water and propionitrile.
  • adiponitrile since it is undesirable that adiponitrile is contained therein, it is desirable to carry out the rectification so that adiponitrile having a higher boiling point may not be distilled.
  • the acrylonitrile rectifying tower mentioned above may be operated not only under atmospheric pressure, but also under a reduced pressure.
  • the use of a reduced pressure has advantages in that the resulting bottom may be separated into two phases without requiring the cooling thereof and that the undesirable side-reactions such as the hydrolysis of adiponitrile and acrylonitrile may be easily prevented because the temperature of the bottom may be maintained at a low level.
  • the bottom obtained in the acrylonitrile rectifying tower is separated into two phases.
  • the bottom may be separated into two phases by allowing the bottom to stand still.
  • an efficient separation can be accomplished by cooling the bottom since, by so doing, the concentration of water and the supporting electrolyte dissolved in the oil phase and the concentration of adiponitrile dissolved in the aqueous phase are decreased.
  • the aqueous phase obtained here is recycled to a catholyte tank.
  • the oil phase mainly consists of adiponitrile and water, and contains a part of the supporting electrolyte.
  • this oil phase is subjected to an extraction with water or a saturated aqueous solution of acrylonitrile containing about 11-7% of acrylonitrile in order to remove supporting electrolyte salt.
  • the supporting electrolyte is extracted with water from the oil phase before removing acrylonitrile therefrom.
  • the supporting electrolyte is extracted with water from the oil phase only after removing acrylonitrile therefrom.
  • countercurrent multiple extractor it is convenient to carry out the extraction by using a countercurrent multiple extractor', because an oil phase containing no supporting electrolyte can be obtained using only a small amount of water.
  • the countercurrent multiple extractor there may be preferably employed the conventional equipment such as packed towers, multiple towers, spray towers, mixer settlers, and pulsating towers.
  • an oil phase containing no supporting electrolyte and an aqueous phase containing supporting electrolyte are obtained. It is convenient to recycle the aqueous phase obtained here to the acrylonitrile rectifying tower explained before.
  • a further feature of the present invention resides in providing an adiponitrile stripper which serves to recover adiponitrile from the bottom of the adiponitrile rectifying tower described hereinafter and charging the distillate obtained in the said stripper directly to a lower boiling component separator positioned prior to the adiponitrile rectifying tower. This prevents intermixing of ethylene cyanohydrin with the adiponitrile.
  • the above described oil phase containing no supporting electrolyte and obtained by the extraction according to the present invention consists mainly of adiponitrile, but contains water and a small amount of acrylonitrile as lower boiling components. To remove the latter, the oil phase is supplied to a lower boiling component separator. This separator is operated with a bottom temperature of 10U-200 C. and the still pressure of 40-50 mm. Hg. Ethylene cyanohydrin which is produced by the thermal decomposition of biscyanoethyl ether by-produced in the electrolysis is also distilled off. As it is not desirable that adiponitrile is distilled oif together therewith, a rectification procedure is recommended.
  • the bottom of the lower boiling component separator mainly consists of adiponitrile, it also contains impurities such as biscyanoethyl ether and oligomers of acrylonitrile (mainly 2-cyanoethyladiponitrile) by-produced in the electrolysis.
  • the bottom is then mainly composed of Z-cyanoethyladiponitrile and biscyanethyl ether. If the residual amount of adiponitrile in the bottom to be discharged is intended to be, for instance, less than 10%, the bottom should be kept at a temperature higher than 220 C. under a high vacuum below 5 mm Hg. Under such conditions of high temperature and high vacuum, biscyanoethyl ether is decomposed thermally to produce acrylonitrile and ethylene cyanohydrin, which would not be intermixed with the product.
  • the boiling point of adiponitrile is 180C. at 25 mm. Hg and 160 C. at l0 mm. Hg
  • two towers may be employed, one being a tower for rectifying adiponitrile (the tower referred to hereinafter as an adiponitrile rectifying tower), and the other being an adiponitrile stripper for separating adiponitrile exhaustively from 2-cyanoethyladponitrile which is a main component of the bottom.
  • the distillate obtained in the adiponitrile stripper is supplied to the above described lower boiling component separator.
  • the bottom temperature of the adiponitrile rectifying tower is chosen so as not to distill otf ethylene cyanohydrin produced by the thermal decomposition of biscyanoethyl ether from the top of the tower. Consequently, the bottom temperature of the adiponitrile rectifying tower is lower than that of the adiponitrile stripper, and the bottom is kept at a high adiponitrile content. Such a bottom is supplied to the adiponitrile stripper.
  • the adiponitrile stripper is kept under such conditions with respect to the degree of vacuum and the temperature of bottom that adiponitrile may be removed from the bottom as completely as possible even when biscyanoethyl ether is decomposed thermally.
  • the bottom of the adiponitrile stripper thus obtained mainly consists of acrylonitrile oligomers of which the main component is 2-cyanoethyladiponitrile and a small amount of the residual supporting electrolyte.
  • the bottom is discharged while the concentration of adiponitrile therein is maintained at less than about 10%.
  • the required number of the rectifying towers is reduced. Since a lesser amount of lower boiling components is mixed in the vapor of the tower rectifying adiponitrile, which is diliicultly rectied, the tower can be kept at a high vacuum easily.
  • the vapor of the low boiling component separator mainly consists of water and contains less materials such as acrylonitrile which have a lower boiling point and are diticult to condense, the tower can be easily kept at a high vacuum and the lower boiling components can be effectively removed.
  • a still further feature of the present invention is to feed the vapor of the above-described acrylonitrile rectifying tower to a propionitrile separator and, after rectifying, to remove propionitrile as the bottom together with water.
  • the vapor of the acrylonitrile rectifying tower mainly consists of acrylonitrile, water, propionitrile and ethylene cyanohydrin.
  • water, propionitrile and ethylene cyanohydrin accumulate in the catholyte, so that they should be discarded out of the system. It is undesirable to entrain acrylonitrile together with them for it causes a decrease in the overall yield of adiponitrile.
  • the vapor discharged from the acrylonitrile rectifying tower is fed to a propionitrile separator to separate a bottom mainly consisting of water, propionitrile and ethylene cyanohydrin and containing little acrylonitrile.
  • the bottom of the propionitrile rectifying tower in the present invention may be discarded, or partially used as an extracting agent in the countercurrent extractor.
  • the vapor of the tower mainly consists of acrylonitrile and water, and when condensed, it separates into two phases, one mainly consisting of acrylonitrile and the other mainly consisting of water.
  • the phase mainly consisting of acrylonitrile is recycled to a catholyte tank to be reused.
  • the phase consisting mainly of water may be recycled and reused as an extracting agent in the extractor.
  • a catholyte 2 in a catholyte tank 1 is kept so that the oil phase and the aqueous phase exist in an emulsion state.
  • the catholyte is fed to a catholyte separating tank 3.
  • the oil phase 4 and the aqueous phase 5 separated here are combined and charged together to an acrylonitrile rectifying tower 7. At this time, it is preferable to feed back .f
  • an irnportant feature of the present invention resides in charging the oil phase and the aqueous phase of the catholyte to an acrylonitrile rectifying tower for treatment together.
  • the catholyte separating tank 3 is thus not necessarily required and the catholyte 2 can be supplied to the acrylonitrile rectifying tower 7 directly.
  • the extract i.e. an aqueous phase containing supporting electrolyte 1S obtained in an extractor 12 is further charged.
  • a distillate 34 of a lower boiling component separator 16 is also charged.
  • a bottom S is obtained by distilling off vapor 25 from these charged solutions. Rectilication is carried out in order that the distilled vapor 2S is mainly composed of acrylonitrile, propionitrile and ethylene cyanohydrin but contains no adiponitrile.
  • the bottom 8 is separated into an oil phase 11 and an aqueous phase 10 in a bottom separator 9 after settling with or without cooling.
  • the aqueous phase 10 is returned to the catholyte tank 1.
  • the oil phase 11 contains supporting electrolyte, the phase is fed to an extractor 12 to remove it.
  • the oil phase 11 is charged at the bottom of the tower, while water or a part of saturated aqueous solution of acrylonitrile 32 obtained in a cooling separator 30 and/or a part 28 of the bottom 27 of a propionitrile separator 26 are charged as an extracting agent at the top of the tower, and then both solutions are contacted countercurrently.
  • aqueous solution 15 containing supporting electrolyte is charged to the acrylonitrile rectifying tower 7.
  • the oil phase 13 free from supporting electrolyte is charged to a lower boiling component separator 16.
  • a distillate 17 consisting mainly of water, acrylonitrile and ethylene cyanohydrin is obtained from the top of the tower. It is preferable in the lower boiling component separator 16 to rectify so that the distillate may contain as little as possible adiponitrile.
  • the distillate 17 is recycled as a feed solution 34 to the acrylonitrile rectifying tower or a feed solution 33 to the propionitrile separator 26.
  • Whether the distillate 17 is used as 34 or 33 is mainly decided depending on the amount of adiponitrile contained in the distillate 17.
  • the adiponitrile content of the distillate 17 is small, it is preferably used as a feed solution to the propionitrile separator.
  • the bottom 18 of the lower boiling component separator 16 is supplied to the adiponitrile rectifying tower 19, Adiponitrile is distilled from the top of this tower as a product 20.
  • the bottom 21 obtained from the bottom of the tower consists mainly of adiponitrile, biscyanoethyl ether and 2-cyanoethyladiponitrile
  • the bottom 21 is fed to lan adiponitrile stripper 22.
  • the adiponitrile stripper 22 it is preferable to discharge the bottom 23 after reducing the content of adiponitrile to less than 10%.
  • the bottom mainly consists of acrylonitrile oligomers (mainly Zfcyanoethyl ether), biscyanoethylether and supporting electrolyte which has not been removed in the extractor.
  • the distillate 2.4 of the adiponitrile stripper 22 is supplied to the lower boiling component separator 16.
  • the vapor 2S of the acrylonitrile rectifying tower 7 is charged to the propionitrile separator 26. From this tower, a liquid 27 containing mainly water, propionitrile and ethylene cyanohydrin is discharged as a bottom. As it is preferable that the bottom contains as little as possible acrylonitrile, rectification is carried out so as to achieve this effect.
  • the distilled vapor from the propionitrile separator 26 is condensed by cooling in a cooling separator 30 and separated into an oil phase 31 mainly consisting of acrylonitrile and an aqueous phase 32 mainly consisting of water.
  • the oil phase 31 is circulated to the catholyte tank 1.
  • the aqueous phase 32 is used as an extracting agent in the extractor 12.
  • the supporting electrolyte in the catholyte used in the process of the present invention should possess an ability of separating the concentrated bottom obtained by distillation of catholyte consisting of the oil and aqueous phases into two phases, and from this aspect, various supporting electrolytes can be used alone or as a mixture, and the degree of concentration of the catholyte and the concentration of the supporting electrolyte in the catholyte may be adequately selected.
  • the supporting electrolyte possessing the said property there may be preferably used mainly sulfates, halides monomethyl sulfates and monoethyl sulfates.
  • the cation of the said supporting electrolyte is preferably the one possessing a lower discharge potential than that at which acrylonitrile is converted to adiponitrile, such as quaternary ammonium ion, ammonium ion and alkali metal ion.
  • an anion polymerization inhibitor as disclosed in U.S. patent application No. 642,321, or a known inhibitor for radical polymerization of acrylonitrile.
  • emulsifying agent animal viscous material, vegetable viscous material and various other synthetic viscous materials.
  • the concentration of the supporting electrolyte used in the catholyte is preferably less than 30%, since the conductivity of the catholyte generally reaches its maximum in the range of concentration of the supporting electrolyte of 1030% by weight in the aqueous phase, and since the aqueous phase should be concentrated later. It is possible, however, to use concentration higher than 30%.
  • the concentration of acrylonitrile in the catholyte and the mixing ratio of the oil phase to the aqueous phase in the catholyte are decided depending on the electrolytic yield of adiponitrile, conductivity of the emulsion and from the standpoint that the amount of acrylonitrile to be treated in the recovering and purifying process should be preferably as small as possible.
  • the optimum values depend on the type of the supporting electrolyte, but in general the acrylonitrile concentration in the oil phase is less than the acrylonitrile concentration in the l'l; aqueous phase is less than and the mixing ratio of the oil phase in the catholyte is less than 50%.
  • EXAMPLE 1 An arrangement was used as shown in the drawing. An emulsion consisting of an aqueous phase and the oil phase having the following composition was employed as a catholyte.
  • composition of the aqueous phase in the catholyte Percent Acrylonitrile 2.0 'Propionitrile 0.2 Ethylene cyanohydrin Trace Adiponitrile 5.6 Acrylonitrile oligomer 0.2 Biscyanoethyl ether Trace ⁇ Water' 74.0 Supporting electrolyte: Percent Tetraethylammonium sulfate 16.0 HeXamethylenediamine sulfate 2.0
  • the catholyte was composed of the above described aqueous phase and oil phase in a ratio of 75 :25 by weight. A part of the catholyte was removed and separated into two layers after settling in the catholyte separator 3. 3 parts of the said oil phase and 1 part of the said aqueous phase were mixed and charged to the acrylonitrile rectifying tower.
  • the bottom of acrylonitrile rectifying tower 7 was kept at a temperature of 110 C. under atmospheric pressure. The bottom was removed, cooled to 30 C. and separated by settling into the oil phase and the aqueous phase having the following compositions.
  • the aqueous phase was returned to the catholyte tank and the oil phase was charged to the packed countercurrent continuous extractor l2 a-t the bottom thereof, and from the top of the extractor the saturated aqueous solution of acrylonitrile 32 obtained in the cooling separator 30 was charged as an extracting agent.
  • the amount of the extracting agent charged was 1/3 of the amount of the oil phase charged.
  • the oil phase was rectified in the lower boiling component separator 16 at the bottom temperature of 180 C. under the still pressure of 40 mm. Hg. At this time the distillate 24 of the adiponitrile stripper 22 having the following composition was added to the solution charged to the lower boiling component separator 16 in an amount of about l/go of the amount of oil phase 13 charged.
  • composition of the distillate of the adiponitrile stripper Percent Ethylene cyanohydrin 1.6 Adiponitrile 40 Biscyanoethyl ether 7 2-cyanoethyladiponitrile 50 Then the bottom 18 having the following composition was obtained from the lower boiling component separator.
  • composition of the bottom of the lower boiling component separator Percent Ethylene cyanohydrin 0.02 Water 0.03 Acrylonitrile 0.01 Adiponitrile 93.3 Acrylonitrile oligomer 6.0 Biscyanoethyl ether 0.6 Supporting electrolyte 0.03
  • the bottom was charged to the adiponitrile rectifying tower 119 and adiponitrile having the purity higher than 99.7% was obtained as the product.
  • the bottom 21 was vaporized in the adiponitrile stripper 22 at the bottom temperature of 215 C. under the still pressure of 4 mm. Hg, and the bottom 23 having the following composition was obtained:
  • the distillate 25 of the acrylonitrile rectifying tower was rectified in the propionitrile separator 26 at the bottom temperature of C. under the still pressure of an atmospheric pressure, and :the bottom 27 having the following composition was obtained:
  • Example 2 The plant setup of Example 1 was used. An emulsion consisting of an aqueous phase and the oil phase having the following composition was employed as the catholyte 2.
  • composition of the aqueous phase in the catholyte Percent Acrylonitrile 1 .0 Propionitrile Trace Ethylene cyanohydrin Do. Adiponi-trile 3.0 Acrylonitrile oligomer Trace Biscyanoethyl ether Do. Water 86 Sodium sulfate 10 pH 4 Composition of the oil phase in the catholyte:
  • the catholyte was composed of the said aqueous phase and oil phase in the mixing ratio of 60:40 by weight. A part of the catholyte was removed and separated by settling in the catholyte separator 3. 4 parts of the oil phase and 1 part of the aqueous phase was mixed and charged to the acrylonitrile rectification tower 7.
  • the acrylonitrile rectifying tower 7 was kept at .the bottom temperature of 108 C. under an atmospheric pressure. The bottom obtained in the said tower was removed, cooled to 40 C. and separated by settling into the oil phase and the aqueous phase having the following cornpositions.
  • Sodium sulfate The aqueous phase was returned to the catholyte tank.
  • the oil phase was charged directly to the lower boiling component separator 16, without passing through the eX- tractor 12 because it contained little supporting electrolyte.
  • a process for recovering adiponitrile from a catholyte emulsion used in the electrolytc hydrodimerization of acrylonitrile which emulsion comprises an oil phase, a continuous aqueous phase, and a supporting electrolyte salt which process comprises directly distilling a mixture of said oil phase and said aqueous phase from said catholyte emulsion to thereby distill off acrylonitrile and water, separating the remaining distillation bottoms into an oil phase and aqueous phase and recovering adiponitrile from the separated oil phase.
  • aqueous extracting agent comprises an aqueous solution of acrylonitrile.

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  • Chemical & Material Sciences (AREA)
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US681203A 1966-11-16 1967-11-07 Process for the recovery of adiponitrile from an electrolytic hydrodimerization by directly distilling the catholyte emulsion Expired - Lifetime US3597331A (en)

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US (1) US3597331A (enrdf_load_stackoverflow)
BE (1) BE706573A (enrdf_load_stackoverflow)
BR (1) BR6794612D0 (enrdf_load_stackoverflow)
CH (1) CH487126A (enrdf_load_stackoverflow)
DE (1) DE1643604B1 (enrdf_load_stackoverflow)
ES (1) ES347183A1 (enrdf_load_stackoverflow)
GB (1) GB1205046A (enrdf_load_stackoverflow)
LU (1) LU54857A1 (enrdf_load_stackoverflow)
NL (1) NL6715362A (enrdf_load_stackoverflow)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3674653A (en) * 1969-05-01 1972-07-04 Asahi Chemical Ind Method of the purification of catholytes
US4623447A (en) * 1985-08-02 1986-11-18 Pennzoil Company Breaking middle phase emulsions
CN102400174A (zh) * 2011-11-30 2012-04-04 青岛双瑞海洋环境工程有限公司 电解丙烯腈二聚制备己二腈的新型装置
WO2021138486A1 (en) * 2019-12-30 2021-07-08 Ascend Performance Materials Operations Llc Process for recovering adiponitrile

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112663078B (zh) * 2020-11-03 2024-12-27 重庆大学 一种丙烯腈电解二聚制备己二腈的装置和方法

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3674653A (en) * 1969-05-01 1972-07-04 Asahi Chemical Ind Method of the purification of catholytes
US4623447A (en) * 1985-08-02 1986-11-18 Pennzoil Company Breaking middle phase emulsions
CN102400174A (zh) * 2011-11-30 2012-04-04 青岛双瑞海洋环境工程有限公司 电解丙烯腈二聚制备己二腈的新型装置
WO2021138486A1 (en) * 2019-12-30 2021-07-08 Ascend Performance Materials Operations Llc Process for recovering adiponitrile
CN114901634A (zh) * 2019-12-30 2022-08-12 奥升德功能材料运营有限公司 回收己二腈的方法
JP2023509915A (ja) * 2019-12-30 2023-03-10 アセンド・パフォーマンス・マテリアルズ・オペレーションズ・リミテッド・ライアビリティ・カンパニー アジポニトリルを回収するためのプロセス

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LU54857A1 (enrdf_load_stackoverflow) 1968-02-09
ES347183A1 (es) 1969-01-16
CH487126A (de) 1970-03-15
DE1643604B1 (de) 1972-08-17
GB1205046A (en) 1970-09-09
BE706573A (enrdf_load_stackoverflow) 1968-05-16
BR6794612D0 (pt) 1973-05-10
NL6715362A (enrdf_load_stackoverflow) 1968-05-17

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