US3335162A - Polymeric impurity removal from an aqueous quaternary ammonium salt solution - Google Patents

Polymeric impurity removal from an aqueous quaternary ammonium salt solution Download PDF

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US3335162A
US3335162A US454740A US45474065A US3335162A US 3335162 A US3335162 A US 3335162A US 454740 A US454740 A US 454740A US 45474065 A US45474065 A US 45474065A US 3335162 A US3335162 A US 3335162A
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solution
quaternary ammonium
ammonium salt
salt
polyacrylonitrile
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US454740A
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Charles R Campbell
Iii Marion J Mathews
Roland R Spiegelhalter
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Monsanto Co
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Monsanto Co
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Priority to US454740A priority Critical patent/US3335162A/en
Priority to LU51019A priority patent/LU51019A1/xx
Priority to IL25695A priority patent/IL25695A/en
Priority to GB19571/66A priority patent/GB1153194A/en
Priority to BE680551D priority patent/BE680551A/xx
Priority to AT435566A priority patent/AT265234B/en
Priority to DK236266AA priority patent/DK117696B/en
Priority to NL6606313A priority patent/NL6606313A/xx
Priority to CH674366A priority patent/CH469654A/en
Priority to JP41029162A priority patent/JPS496296B1/ja
Priority to DE19661593014 priority patent/DE1593014A1/en
Priority to FR60972A priority patent/FR1479119A/en
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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

Definitions

  • Adiponitrile can be produced by electrohydrodimerizing acrylonitrile.
  • the electrohydrodimerization is carried out in an electrolytic cell having an anode chamber and a cathode chamber separated by an ion exchange resin.
  • Acrylonitrile is dissolved in an aqueous quaternary ammonium salt solution.
  • This solution i.e., catholyte
  • a dilute acid solution i.e., anolyte
  • An electrical potential is established between the anode and cathode sufficient to produce a unidirectional current flow.
  • acrylonitrile is reductively dimerized to adiponitrile at the cathode.
  • the catholyte is then extracted with acrylonitrile to remove adiponitrile plus a small quantity of certain byproducts, e.g., propionitn'le, bis-cyanoethylether, hydroxypropionitrile, etc.
  • the acrylonitrile plus other products is in turn water-Washed to remove any dissolved quaternary ammonium salt.
  • the aqueous quaternary ammonium salt raflinate from the acrylonitrile extraction plus any aqueous quaternary ammonium salt solution obtained from water-washing the acrylonitrile extract are evaporated to the proper quaternary ammonium salt concentration before the quaternary ammonium salt solution is returned to the catholyte circulating system.
  • the salt employed in the electrohydrodimerization of acrylonitrile to adiponitrile must serve two functions: one, the salt must conduct electrical current and, two, it must act to dissolve acrylonitrile in the aqueous solution of salt, i.e., the salt must be hydrotropic.
  • Quaternary ammonium salts have been found to be admirably suited for such purposes. Included among the suitable quaternary ammonium salts are, generally, tetraalkylammonium sulfates, tetralkylammonium aryl sulfonates, and tetraalkylammonium alkyl sulfates.
  • Two specifically useful salts are tetramethylammonium toluene sulfonate and tetraethylammonium ethyl sulfate.
  • quaternary ammonium salt solution must be kept substantially free of impurities.
  • One impurity formed in the electrohydrodi- Inerization process is polyacrylonitrile. Most of this material is removable by ordinary filtration or like processes for removing solids from liquids. Nevertheless, small quantities of polyacrylonitrile partially hydrolyze to produce a polymer having sufiicient carboxylate groups to make it readily soluble in quaternary ammonium salt solution.
  • a further object is to substantially remove organic impurities, especially polyacrylonitrile, from an aqueous solution of quaternary ammonium salt.
  • a still further object is to improve, by reducing all cathode fouling, the product yield in the electrohydrodimerization of acrylonitrile to adiponitrile.
  • the above objects are achieved by providing a process wherein the above noted partially hydrolyzed polyacrylonitrile is removed from an aqueous solution of a hydrotropic quaternary ammonium salt by means of a procedure including precipitating the polyacrylonitrile by adjusting the salt concentration of the solution to not more than about 55 weight percent and adjusting the pH of the aqueous solution to not more than about 7. This precipitated material is then separated from the aqueous salt solution.
  • the treated quaternary ammonium salt solution have a concentration of not more than about 55 weight percent and a pH of notlmore than about 7, i.e., be neutral or acidic.
  • concentration not more than about 55 weight percent
  • pH notlmore than about 7
  • concentration is more than 55 weight percent then it is only necessary to decrease the salt concentration to achieve the proper precipitating conditions.
  • both concentration and pH are above the maximum limits then it is necessary to lower the salt concentration, i.e., dilute the solution, and to put suflicient acid in the solution to make it acidic.
  • the order in which the concentration adjustment and pH adjustment takes place may vary.
  • the solution can be made acidic then have the concentration adjusted or the concentration can be adjusted, then the solution can be made acidic.
  • the salt concentration is greater than about 55 weight percent and the pH is greater than 7, i.e., alkaline, the solution can be simultaneously diluted and acidified with a proper quantity of an aqueous acid solution.
  • the most effective precipitation occurs when the pH is not more than about 7 and the salt concentration is not more than about 40 weight percent.
  • the preferred acids used to acidify the salt solution are those whose anion corresponds to the anion of the quaternary ammonium salt being treated, for instance, when tetraethylammonium ethyl sulfate is the salt the acid should be ethyl sulfuric acid.
  • the procedure can be performed in batch form or it can be performed upon a continuous stream.
  • the methods for separating the precipitated material from the salt I solution include filtering, centrifuging, and other like processes well known to persons skilled in the art..
  • Example I A quantity of tetramethylammonium toluene sulfonate that had been recycled 25 times through the electrolytic cell employed to electrohydrodimerize acrylonitrile to adiponitrile was so concentrated by a series of concentration and crystallization procedures until the level of organic impurities present in the aqueous salt was approximately equivalent to that quantity of organic impurities that would have been present if the salt had been recycled about times.
  • This salt having a large quantity of organic impurities therein, was then employed as the supporting electrolyte in the catholyte used in electrohydrodimerizing acrylonitrile to adiponitrile.
  • the catholyte included 25 weight percent acrylonitrile (45.9 weight percent tetramethylammonium toluene sulfonate, and 29.1 weight percent water.
  • the pH was 9.0.
  • the diluted salt solution from which the partially hydrolyzed polyacrylonitrile had been removed was reconcentrated and had the pH readjusted, and had enough acrylonitrile added thereto to produce a catholyte substantially equivalent to that described above, i.e., the pH was adjusted to about 9.0 with tetramethylammonium hydroxide, acrylonitrile concentration to about 25 weight percent, tetramethylammonium toluene sulfonate concentration to about 45.9 weight percent and about 29.1 weight percent of thecatholyte was water.
  • This catholyte was used in the same cell as was the contaminated electrolyte and was run for the same period of time, six hours.
  • Table l were obtained. All amounts are given as weight percent based on the total product weight.
  • Example 11 TABLE 2. COMPARATIVE POLYMER REMOVAL RESULTS Salt concentra- Amount of polymer tion, weight pH removed, weight perpercent cent based on diy salt Thus, it is clear that once the pH of the diluted salt becomes greater than 7.0 polymer removal becomes negligible. However, as can be seen from Example 1, best results are obtained when the salt concentration and pH 5 are lower. than set out in this example.
  • the primary advantage of this invention is the significant improvement in adiponitrile yield.
  • a second advantage is the increased useful life span of a particular cathode, i.e., the cathode becomes fouled at a much slower rate when the electrolyte is substantially free of organic impurities-such as polyacrylonitrile, thus increasing the periods between cathode cleanmg.
  • hydrotropic quaternary ammonium salt is a tetraalkylammonium aryl sulfonate.
  • a process for removing partially hydrolyzed polyacrylonitrile from an aqueous salt solution of ,a hydrotropic quaternary. ammonium salt comprising, in combination, the steps of:
  • quaternary ammonium salt is a tetraalkylammonium alkyl 5 6 (b) separating said polyacrylonitrile from said aqueous References Cited Solution UNITED STATE PAT N s 7.
  • the hydrotropic qua- S E T ternary ammonium salt is tetraethylammonium ethyl 3,193,481 7/1965 Bauer 204 '73 Sulfate 5 CHARLES B. PARKER, Primary Examiner.
  • hydrotropic quaternary ammonium salt is tetramethylammonium toluene BERNARD BILLIAN, Assistant Examiner.

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  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
  • Electrolytic Production Of Non-Metals, Compounds, Apparatuses Therefor (AREA)

Description

Unite States Patent O 3,335,162 POLYMERIC IMPURITY REMOVAL FROM AN AQUEOUS QUATERNARY AMMONIUM SALT SOLUTION Charles R. Campbell, Marion J. Mathews Ill, and Roland R. Spiegelhalter, Pensacola, Fla, assignors to Monsanto Company, St. Louis, Mo., a corporation of Delaware No Drawing. Filed May 10, 1965, Ser. No. 454,740 8 Claims. (Cl. 260-459) This invention relates to removing certain organic impurities from an aqueous solution of a hydrotropic quaternary ammonium salt.
Adiponitrile can be produced by electrohydrodimerizing acrylonitrile. The electrohydrodimerization is carried out in an electrolytic cell having an anode chamber and a cathode chamber separated by an ion exchange resin. Acrylonitrile is dissolved in an aqueous quaternary ammonium salt solution. This solution, i.e., catholyte, is then continuously circulated through the cathode compartment while a dilute acid solution, i.e., anolyte, is circulated through the anode compartment. An electrical potential is established between the anode and cathode sufficient to produce a unidirectional current flow. Thus acrylonitrile is reductively dimerized to adiponitrile at the cathode.
The catholyte is then extracted with acrylonitrile to remove adiponitrile plus a small quantity of certain byproducts, e.g., propionitn'le, bis-cyanoethylether, hydroxypropionitrile, etc. The acrylonitrile plus other products is in turn water-Washed to remove any dissolved quaternary ammonium salt. The aqueous quaternary ammonium salt raflinate from the acrylonitrile extraction plus any aqueous quaternary ammonium salt solution obtained from water-washing the acrylonitrile extract are evaporated to the proper quaternary ammonium salt concentration before the quaternary ammonium salt solution is returned to the catholyte circulating system.
The salt employed in the electrohydrodimerization of acrylonitrile to adiponitrile must serve two functions: one, the salt must conduct electrical current and, two, it must act to dissolve acrylonitrile in the aqueous solution of salt, i.e., the salt must be hydrotropic. Quaternary ammonium salts have been found to be admirably suited for such purposes. Included among the suitable quaternary ammonium salts are, generally, tetraalkylammonium sulfates, tetralkylammonium aryl sulfonates, and tetraalkylammonium alkyl sulfates. Two specifically useful salts are tetramethylammonium toluene sulfonate and tetraethylammonium ethyl sulfate.
Under the described evaporation and recycle procedure a given batch of quaternary ammonium salt is repeatedly reused. For efiicient cell operation the quaternary ammonium salt solution must be kept substantially free of impurities. One impurity formed in the electrohydrodi- Inerization process is polyacrylonitrile. Most of this material is removable by ordinary filtration or like processes for removing solids from liquids. Nevertheless, small quantities of polyacrylonitrile partially hydrolyze to produce a polymer having sufiicient carboxylate groups to make it readily soluble in quaternary ammonium salt solution. In one sample of aqueous quaternary ammonium salt which had been recycled 25 times partially hydrolyzed polyacryonitrile was found to be present at a level of about 0.1 percent based on the solution weight. Even this extremely small quantity deposits on the cell cathode thereby fouling same and substantially reducing the electrolydrodimerization yield. On analysis it was determined that the major portion of the material fouling the cathode consisted of deposited polyacrylontrile plus small quantities of quaternary ammonium salt.
It is a general object of this invention to eliminate or substantially reduce cathode fouling in a cell used in the electrohydrodimerization of acrylonitrile to adiponitrile.
A further object is to substantially remove organic impurities, especially polyacrylonitrile, from an aqueous solution of quaternary ammonium salt.
A still further object is to improve, by reducing all cathode fouling, the product yield in the electrohydrodimerization of acrylonitrile to adiponitrile.
Other objects will become apparent upon reading the following descriptive material.
In general, the above objects are achieved by providing a process wherein the above noted partially hydrolyzed polyacrylonitrile is removed from an aqueous solution of a hydrotropic quaternary ammonium salt by means of a procedure including precipitating the polyacrylonitrile by adjusting the salt concentration of the solution to not more than about 55 weight percent and adjusting the pH of the aqueous solution to not more than about 7. This precipitated material is then separated from the aqueous salt solution.
To achieve proper polyacrylonitrile precipitation requires that the treated quaternary ammonium salt solution have a concentration of not more than about 55 weight percent and a pH of notlmore than about 7, i.e., be neutral or acidic. There are various ways to achieve these conditions, depending upon the initial condition of the solution, of course. When the solution is already acidic but the concentration is more than 55 weight percent then it is only necessary to decrease the salt concentration to achieve the proper precipitating conditions. When both concentration and pH are above the maximum limits then it is necessary to lower the salt concentration, i.e., dilute the solution, and to put suflicient acid in the solution to make it acidic.
The order in which the concentration adjustment and pH adjustment takes place may vary. The solution can be made acidic then have the concentration adjusted or the concentration can be adjusted, then the solution can be made acidic. When the salt concentration is greater than about 55 weight percent and the pH is greater than 7, i.e., alkaline, the solution can be simultaneously diluted and acidified with a proper quantity of an aqueous acid solution.
The most effective precipitation occurs when the pH is not more than about 7 and the salt concentration is not more than about 40 weight percent.
The preferred acids used to acidify the salt solution, because it is desirable not to contaminate the electrolyte with extraneous acids, are those whose anion corresponds to the anion of the quaternary ammonium salt being treated, for instance, when tetraethylammonium ethyl sulfate is the salt the acid should be ethyl sulfuric acid.
The procedure can be performed in batch form or it can be performed upon a continuous stream. The methods for separating the precipitated material from the salt I solution include filtering, centrifuging, and other like processes well known to persons skilled in the art..
The examples below are set out to more fully illustrate the invention. It is not intended that the examples limit the invention in any manner whatsoever.
Example I A quantity of tetramethylammonium toluene sulfonate that had been recycled 25 times through the electrolytic cell employed to electrohydrodimerize acrylonitrile to adiponitrile was so concentrated by a series of concentration and crystallization procedures until the level of organic impurities present in the aqueous salt was approximately equivalent to that quantity of organic impurities that would have been present if the salt had been recycled about times. This salt, having a large quantity of organic impurities therein, was then employed as the supporting electrolyte in the catholyte used in electrohydrodimerizing acrylonitrile to adiponitrile. The catholyte included 25 weight percent acrylonitrile (45.9 weight percent tetramethylammonium toluene sulfonate, and 29.1 weight percent water. The pH was 9.0.
Upon conclusion of this test, which lasted for six hours, using highly contaminated electrolyte the catholyte was extracted with acrylonitrile to recover the adiponitrile and other like organic products. The remaining tetramethylammonium toluene sulfonate solution was adjusted to a salt concentration of 12 weight percent and the pH was adjusted to about 1 with p-toluene sulfonic acid. Immediately a precipitate appeared. This precipitate was then filtered from the salt solution and was determined to be about 0.8 weight percent of the salt solution based on the dry salt.
The diluted salt solution from which the partially hydrolyzed polyacrylonitrile had been removed was reconcentrated and had the pH readjusted, and had enough acrylonitrile added thereto to produce a catholyte substantially equivalent to that described above, i.e., the pH was adjusted to about 9.0 with tetramethylammonium hydroxide, acrylonitrile concentration to about 25 weight percent, tetramethylammonium toluene sulfonate concentration to about 45.9 weight percent and about 29.1 weight percent of thecatholyte was water. This catholyte was used in the same cell as was the contaminated electrolyte and was run for the same period of time, six hours. Upon analysis of the acrylonitrile extracted prodnot of electrohydrodimerization the results shown in Table l were obtained. All amounts are given as weight percent based on the total product weight.
TAB LE 1 Products Obtained Contrmlitnated Purified Salt Adiponitrile 72. 33 83. 05 Propionitrile r 9. 74 9. 46 BiS-cyanoethylethen. 13. 60 2. 62 Hydroxypropionitrile 0. 97 0. 43 Other high boiling impurities 3. 36 4. 44
1 Principally Z-cyanoethyladiponitrile.
From the results in Table 1, it is quite apparent that the production of the desired product, adiponitrile, is
substantially increased by removal of the partially hydrolyzed polyacrylonitrile produced in the electrohydrodimerization process.
Example 11 TABLE 2. COMPARATIVE POLYMER REMOVAL RESULTS Salt concentra- Amount of polymer tion, weight pH removed, weight perpercent cent based on diy salt Thus, it is clear that once the pH of the diluted salt becomes greater than 7.0 polymer removal becomes negligible. However, as can be seen from Example 1, best results are obtained when the salt concentration and pH 5 are lower. than set out in this example.
It can be readily seen that the primary advantage of this invention is the significant improvement in adiponitrile yield. A second advantage is the increased useful life span of a particular cathode, i.e., the cathode becomes fouled at a much slower rate when the electrolyte is substantially free of organic impurities-such as polyacrylonitrile, thus increasing the periods between cathode cleanmg.
Although the invention has been described by reference to particular embodiments and examples, it is evident that many other embodiments and variations would be apparentto those skilled in the art to which the invention pertains. Therefore, the invention should be broadly construed and should only be limitedto the reasonable scope of the appended claims.
What is claimed is:
1.A process for. removing partially hydrolyzed polyacrylonitrile from an aqueous solution of a hydrotropic quaternary ammonium salt comprising, in combination, the steps of:
(a) precipitating said polyacrylonitrile by adjusting the salt concentration of said solution to not more than about 55 weight percent and adjusting the pH of said solution to not more than about 7; and
(b) separating said polyacrylonitrile from said solution.
2. The process of claim 1 wherein the hydrotropic quaternary ammonium salt is a tetraalkylammonium aryl sulfonate.
3. The process of claim 1 wherein the hydrotropic sulfate.
4. A process for removing partially hydrolyzed polyacrylonitrile from an aqueous salt solution of ,a hydrotropic quaternary. ammonium salt comprising, in combination, the steps of:
(a) precipitating said polyacrylonitrile by sequentially,
(1) adding sufiicient water to said aqueous solution to adjust the salt concentration thereof to not more than about 40 weight percent, (2) acidifying said aqueous solution to adjust the tropic quaternary ammonium salt comprising, in combination, the steps of:
(a) precipitating said polyacrylonitrile by sequentially, (1) acidifying said aqueous salt solution to adjust the pH thereofto notmore than about 7;
(2) adding sufiicient water tosaid aqueous salt solution having a pH of not more than about 7 to adjust the salt concentration thereof to not more than about 40 weight percent; and
(b) separating said polyacrylonitrile from said aqueous solution.
6.-A process for removing partially hydrolyzed polyacrylonitrile from an aqueous solution of a hydrotropic quaternary ammonium salt-selected from the group consisting of tetraalkylammonium alkyl sulfates and tetraalkylammonium aryl sulfonates used as a supporting electrolyte in a process for electrohydrodimerizing acrylonitrile to adiponitrile comprising, in combination, the 7 steps of:
(a) precipitating said partially hydrolyzed polyacrylonitrile by adjusting the salt concentration of said solution to not more than about 40 weight percent and adjusting the pH of said solution to not more than about 7; and
quaternary ammonium salt is a tetraalkylammonium alkyl 5 6 (b) separating said polyacrylonitrile from said aqueous References Cited Solution UNITED STATE PAT N s 7. The process of claim 6 wherein the hydrotropic qua- S E T ternary ammonium salt is tetraethylammonium ethyl 3,193,481 7/1965 Bauer 204 '73 Sulfate 5 CHARLES B. PARKER, Primary Examiner.
8. The process of claim 6 wherein the hydrotropic quaternary ammonium salt is tetramethylammonium toluene BERNARD BILLIAN, Assistant Examiner.
sulfonate.

Claims (1)

1. A PROCESS FOR REMOVING PARTIALLY HYDROLYZED POLYACRYLONITRILE FROM AN AQUEOUS SOLUTION OF A HYDROTROPIC QUATERNARY AMMONIUM SALT COMPRISING, IN COMBINATION, THE STEPS OF: (A)PRECIPITATING SAID POLYACRYLONITRILE BY ADJUSTING THE SALT CONCENTRATION OF SAID SOLUTION TO NOT MORE THAN ABOUT 55 WEIGHT PERCENT AND ADJUSTING THE PH OF SAID SOLUTION TO NOT MORE THAN ABOUT 7; AND (B) SEPARATING SAID POLYACRYLONITRILE FROM SAID SOLUTION.
US454740A 1965-05-10 1965-05-10 Polymeric impurity removal from an aqueous quaternary ammonium salt solution Expired - Lifetime US3335162A (en)

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Application Number Priority Date Filing Date Title
US454740A US3335162A (en) 1965-05-10 1965-05-10 Polymeric impurity removal from an aqueous quaternary ammonium salt solution
LU51019A LU51019A1 (en) 1965-05-10 1966-05-03
IL25695A IL25695A (en) 1965-05-10 1966-05-03 Polymeric impurity removal from an aqueous quaternary ammonium salt solution used in electrohydrodimerization of acrylonitrile
GB19571/66A GB1153194A (en) 1965-05-10 1966-05-03 Polymeric Impurity Removal from an Aqueous Quaternary Ammonium Salt Solution
BE680551D BE680551A (en) 1965-05-10 1966-05-05
DK236266AA DK117696B (en) 1965-05-10 1966-05-09 Process for removing partially hydrolyzed polyacrylonitrile from an aqueous solution of a hydrotropic quaternary ammonium salt.
AT435566A AT265234B (en) 1965-05-10 1966-05-09 Process for the partial removal of hydrolyzed polyacrylonitrile from an aqueous solution of a hydrotopic quaternary ammonium salt
NL6606313A NL6606313A (en) 1965-05-10 1966-05-09
CH674366A CH469654A (en) 1965-05-10 1966-05-10 Process for removing partially hydrolyzed polyacrylonitrile from an aqueous solution of a hydrotropic quaternary ammonium salt
JP41029162A JPS496296B1 (en) 1965-05-10 1966-05-10
DE19661593014 DE1593014A1 (en) 1965-05-10 1966-05-10 Process for removing certain organic contaminants
FR60972A FR1479119A (en) 1965-05-10 1966-05-10 Improvements in the production of adiponitrile from acrylonitrile

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JP (1) JPS496296B1 (en)
AT (1) AT265234B (en)
BE (1) BE680551A (en)
CH (1) CH469654A (en)
DE (1) DE1593014A1 (en)
DK (1) DK117696B (en)
GB (1) GB1153194A (en)
IL (1) IL25695A (en)
LU (1) LU51019A1 (en)
NL (1) NL6606313A (en)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3402112A (en) * 1965-07-26 1968-09-17 Monsanto Co Process for reducing anode corrosion in an acrylonitrile hydrodimerization cell
US3493597A (en) * 1967-05-25 1970-02-03 Monsanto Co Purification of aqueous quaternary ammonium salt solutions
US3664936A (en) * 1969-05-08 1972-05-23 Asahi Chemical Ind Electrolytic hydrodimerization of acrylonitrile
US4072713A (en) * 1972-07-27 1978-02-07 Phillips Petroleum Company Method for separating tetraalkylammonium salts

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3193481A (en) * 1962-10-05 1965-07-06 Monsanto Co Electrolytic hydrodimerization alpha, beta-olefinic nitriles

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3193481A (en) * 1962-10-05 1965-07-06 Monsanto Co Electrolytic hydrodimerization alpha, beta-olefinic nitriles

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3402112A (en) * 1965-07-26 1968-09-17 Monsanto Co Process for reducing anode corrosion in an acrylonitrile hydrodimerization cell
US3493597A (en) * 1967-05-25 1970-02-03 Monsanto Co Purification of aqueous quaternary ammonium salt solutions
US3664936A (en) * 1969-05-08 1972-05-23 Asahi Chemical Ind Electrolytic hydrodimerization of acrylonitrile
US4072713A (en) * 1972-07-27 1978-02-07 Phillips Petroleum Company Method for separating tetraalkylammonium salts

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AT265234B (en) 1968-10-10
IL25695A (en) 1970-02-19
NL6606313A (en) 1966-11-11
DE1593014A1 (en) 1970-04-16
GB1153194A (en) 1969-05-29
DK117696B (en) 1970-05-25
BE680551A (en) 1966-11-07
LU51019A1 (en) 1966-11-03
CH469654A (en) 1969-03-15
JPS496296B1 (en) 1974-02-13

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