CA1042464A - Treatment of adiponitrile with boron phosphate or bentonite - Google Patents
Treatment of adiponitrile with boron phosphate or bentoniteInfo
- Publication number
- CA1042464A CA1042464A CA000234358A CA234358A CA1042464A CA 1042464 A CA1042464 A CA 1042464A CA 000234358 A CA000234358 A CA 000234358A CA 234358 A CA234358 A CA 234358A CA 1042464 A CA1042464 A CA 1042464A
- Authority
- CA
- Canada
- Prior art keywords
- adiponitrile
- water
- bentonite
- crude
- treated
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C255/00—Carboxylic acid nitriles
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Catalysts (AREA)
Abstract
ABSTRACT OF THE DISCLOSURE
A process for reducing the amount of basic impurities, especially N-heterocyclic compounds, in adipo-nitrile is disclosed. The process comprises treating adiponitrile with boron phosphate or bentonite. The adiponitrile is preferably treated in the presence of water and in particular in the additional presence of a water-soluble acidic compound. The process is particularly useful in the purification of adiponitrile manufactured from adipic acid and ammonia.
A process for reducing the amount of basic impurities, especially N-heterocyclic compounds, in adipo-nitrile is disclosed. The process comprises treating adiponitrile with boron phosphate or bentonite. The adiponitrile is preferably treated in the presence of water and in particular in the additional presence of a water-soluble acidic compound. The process is particularly useful in the purification of adiponitrile manufactured from adipic acid and ammonia.
Description
m e present invention relates to the treatment of adiponitrile wlth boron phosphate or bentonite and in particular to a process for reducing the amount o~ basic impurities in crude adlponitrile in which the crude adiponitrile is treated with boron phosphate or bentoniteO
One o~ the more important uses o~ ad~ponitrile at the present time is in the manu~acture of hexamethylene dlamineJ
This diamine may be used as a detergent, as an emulsi~ying agent, or in particularg as an intermediate in the manufacture o~ polymersO ~ catalytic hydrogenation reaction is usually employed to convert adiponitrile to hexamethylene diam~ne~
There are several methods for synthesi~ing adipo~
nitrileO In particular, adiponitrile may be obtained by react- -ing adipic acid with ammonia in the presence o~ a dehydrating catalyst, ~or example, by the technigues disclosed ~n UOSO
Patent 23 200,734 of Arnold and Lazier which issued May 14, 1940 and in U.SO Patent 2,273,633 of M~LoA~ ~luchaire which ~ssued February 17, 19420 Adiponitrile, especially adiponitrile obtained ~rom adipic acid, contains impurities, some of which boil at temperatures close to the boiling point of adiponitrileO
One o~ the more important uses o~ ad~ponitrile at the present time is in the manu~acture of hexamethylene dlamineJ
This diamine may be used as a detergent, as an emulsi~ying agent, or in particularg as an intermediate in the manufacture o~ polymersO ~ catalytic hydrogenation reaction is usually employed to convert adiponitrile to hexamethylene diam~ne~
There are several methods for synthesi~ing adipo~
nitrileO In particular, adiponitrile may be obtained by react- -ing adipic acid with ammonia in the presence o~ a dehydrating catalyst, ~or example, by the technigues disclosed ~n UOSO
Patent 23 200,734 of Arnold and Lazier which issued May 14, 1940 and in U.SO Patent 2,273,633 of M~LoA~ ~luchaire which ~ssued February 17, 19420 Adiponitrile, especially adiponitrile obtained ~rom adipic acid, contains impurities, some of which boil at temperatures close to the boiling point of adiponitrileO
2-Cyanocyclopentylideneimine~ hereina~ter sometimes referred to as CPI, is an example o~ such aM impurity, Close boillng impurities ~requently cannot be removed e~ficiently in industrial scale distillation columnsO Impurities in the adiponitr~le may lead to impuritles in subsequent deriviatives, in particular in hexamethylene dlamine, that are di~lcult to removeO Failure to remove these latter impurities may result in in~erior and variable product properties, especially in polymers manufactured using such impure hexamethylene diamin2. Techniques , . . ..
:,, . : -... . . .
.. - . . . .
~ ., .
2Z9~Z~
~or the purif`ication o~ adiponitrile are known in the art~
For example, adiponitrile Zmay be treated with a ~olid acidic catalyst in the presence o~ water and at a temperature of at least 140C to remove 2--cyanocyclopZ0ntylideneimine from the adiponitrileO The solid acidic catalysts may be silica-alumina catalystsg crystalline aluminosilicates, boron phosphate or titania-aluminaO Such treatment is described in Canadi~n Patent 912,036 of Bo JD Kershaw which issued October 10, 1972.
Adiponitrile, especially adlponitrile obtained from the reaction o~ adipic acid with ammonia may also contaln impurities in the form of cyclic amines, especially N-heterocycllc : compoundsO Examples of such impurities are 2~methyl-4-amino-5, : -6-trimethylene pyrimidine, hereinafter sometimes referred to as MAP, 2-amino~3,4,5,6 bis(trimethylene) pyridine, hereinafter ~ !
sometimes referred to as ABP, and 2~cyclopentyl-4 amino-5,6-tri-methylene pyrimidine, hereinafter sometimes referred to as VAPo Such N-heterocyclic compounds may cause process problems in the hydrogenation of adiponitrile to hexamethglene diamine or in the subsequent puri~ication of the hexamethylene diamine It has now been found that basic impurities, especially N-heterocyclic compounds, may be removed from crude ad~ponitrile by treating the adiponitrile with boron phosphate or bentonite at relat~vely low temperatures.
Accordinglyg the present invention provides a process for reducing the amount o~ basic impurities in crude adiponitrile, ~ said pro¢ess comprising the steps of contacting crude adipo-.
Z nitrile with material selected from the group consisting of boron phosphate and bentonite, and mixtures thereof3 at a temperature in the range 20 100Co In a preferred embodiment o~ the process of the pre~ent invention the adiponitrile is treated substantially in the absence of a~moniaO
-,.. .,.
,: . .
In another embodiment the adiponitrile is treated in the presence o~ water.
In a further embodiment the crude adiponitrile i8 adiponitrile th~t has been manu~actured ~rom adipic acid and ammonia, In the process of the present invention the crude adiponitrlle is treated with a material selected ~rom the group consisting o~ boron phosphate and bentonite, and mixtures thereof. In the process the adiponitrile maybe treated by contacting the adipon~trile and the makerlal in a continuous process or in a batch process, the ~ormer being pre~erred. Preferably the adiponitrile is passed through a ~ixed bed of the boron phosphate or bentonite.
Wh~le the adiponitrile treated by the process of the present invention is described as l'crude adipônitrile" the adiponitrile being treated is prefera~ly adiponitrile that has been subjected to partial puri~ication e.g. by distillatlon.
Crude adiponitrile is treated by the process of the present invention for the removal of basic im~urities, especially the aforementioned N-heterocyclic compoundsO In particular, the adiponitrile ~s adiponitrile manuf~ctured ~rom adipic acid and ammonia. The basic impurities are removed from the adiponitrile by retention on the boron phosphate or bentonite.
In the process o~ the present invention the adiponitrile is pre~erably treated substantially in the absence o~ ammonia.
Ammonia may be pre~erentially absorbed on the ~oron phosphate or bentonlte and such pre~erential absorption might result in the desorption o~ N-heterocyclic compounds a~sorbed on the boron p~osphate or bentonite~ The effects of preferential , absorption of ammonia depend at least in part on the concentra tion of ammoni~, as will be understood by those skilled in the artO Relatlvely high concentrations o~ ammon~a may be used in the regeneration of ~oron pAosphate and bentoniteg as is described hereinafter.
:,, . : -... . . .
.. - . . . .
~ ., .
2Z9~Z~
~or the purif`ication o~ adiponitrile are known in the art~
For example, adiponitrile Zmay be treated with a ~olid acidic catalyst in the presence o~ water and at a temperature of at least 140C to remove 2--cyanocyclopZ0ntylideneimine from the adiponitrileO The solid acidic catalysts may be silica-alumina catalystsg crystalline aluminosilicates, boron phosphate or titania-aluminaO Such treatment is described in Canadi~n Patent 912,036 of Bo JD Kershaw which issued October 10, 1972.
Adiponitrile, especially adlponitrile obtained from the reaction o~ adipic acid with ammonia may also contaln impurities in the form of cyclic amines, especially N-heterocycllc : compoundsO Examples of such impurities are 2~methyl-4-amino-5, : -6-trimethylene pyrimidine, hereinafter sometimes referred to as MAP, 2-amino~3,4,5,6 bis(trimethylene) pyridine, hereinafter ~ !
sometimes referred to as ABP, and 2~cyclopentyl-4 amino-5,6-tri-methylene pyrimidine, hereinafter sometimes referred to as VAPo Such N-heterocyclic compounds may cause process problems in the hydrogenation of adiponitrile to hexamethglene diamine or in the subsequent puri~ication of the hexamethylene diamine It has now been found that basic impurities, especially N-heterocyclic compounds, may be removed from crude ad~ponitrile by treating the adiponitrile with boron phosphate or bentonite at relat~vely low temperatures.
Accordinglyg the present invention provides a process for reducing the amount o~ basic impurities in crude adiponitrile, ~ said pro¢ess comprising the steps of contacting crude adipo-.
Z nitrile with material selected from the group consisting of boron phosphate and bentonite, and mixtures thereof3 at a temperature in the range 20 100Co In a preferred embodiment o~ the process of the pre~ent invention the adiponitrile is treated substantially in the absence of a~moniaO
-,.. .,.
,: . .
In another embodiment the adiponitrile is treated in the presence o~ water.
In a further embodiment the crude adiponitrile i8 adiponitrile th~t has been manu~actured ~rom adipic acid and ammonia, In the process of the present invention the crude adiponitrlle is treated with a material selected ~rom the group consisting o~ boron phosphate and bentonite, and mixtures thereof. In the process the adiponitrile maybe treated by contacting the adipon~trile and the makerlal in a continuous process or in a batch process, the ~ormer being pre~erred. Preferably the adiponitrile is passed through a ~ixed bed of the boron phosphate or bentonite.
Wh~le the adiponitrile treated by the process of the present invention is described as l'crude adipônitrile" the adiponitrile being treated is prefera~ly adiponitrile that has been subjected to partial puri~ication e.g. by distillatlon.
Crude adiponitrile is treated by the process of the present invention for the removal of basic im~urities, especially the aforementioned N-heterocyclic compoundsO In particular, the adiponitrile ~s adiponitrile manuf~ctured ~rom adipic acid and ammonia. The basic impurities are removed from the adiponitrile by retention on the boron phosphate or bentonite.
In the process o~ the present invention the adiponitrile is pre~erably treated substantially in the absence o~ ammonia.
Ammonia may be pre~erentially absorbed on the ~oron phosphate or bentonlte and such pre~erential absorption might result in the desorption o~ N-heterocyclic compounds a~sorbed on the boron p~osphate or bentonite~ The effects of preferential , absorption of ammonia depend at least in part on the concentra tion of ammoni~, as will be understood by those skilled in the artO Relatlvely high concentrations o~ ammon~a may be used in the regeneration of ~oron pAosphate and bentoniteg as is described hereinafter.
3 -; ., . :
;4 Crude adiponitrile may be treated, according to the process of the present invention, in the presence or ab~ence of water. Pre~erably the adiponitrlle ls treated in the presence of water In a preferred embodiment the adiponitri~e is treated : in the presence Or both water ~nd a water-soluble acidlc compound especially phosphoric or acetic acid, If treated ln the presence o~ water, it is preferred~ for economic reasons that there are not more than two parts water per one part of adipon~trile, on a weight basis Preferably, the adlponitrile contains 1 to 10~ by weight of waterO
The process of the present lnvention may be carried out at temperatures in the range 20-100C. Treatment may occur at lower temperatures at low ratesO At higher temperatures, especially above 140C and in the presence of water, hydrolysis of 2-cyanocyclopentylideneimine~ which ma~ be present in the ;. crude adiponitrile, may occur. Such hydrol~sis of 2-cyanocyclopentylideneimine is disclosed in the aforementioned Canadian Patent 912,036O
: The pressure used.in the process of the present 20 inventlon is not critlcalO The pressure will depend primarily .:
on other process variables, for example, the temperature at wh~ch the process is operatedO
After operating the process for a period of time it may be desirable or necessary to replace and/or regenerate the boron phosphate or bentoniteO To regenerate used boron phos-: phate or bentonite, the boron pho3phate or bentonite may be heated under an atmosphere of lnert gas, treated with st~am at high temperatures or treated with a base of hlgher af~inity for the boron phosphate or bentonite ~ollowed by treatment to remove ~he baseO For example, the boron phosphate or bentonite may be contacted with an ammonia solution at a temperature of ~rom ambient to about 70C, separated there~rom and heated to remove ammoniaO
;4 Crude adiponitrile may be treated, according to the process of the present invention, in the presence or ab~ence of water. Pre~erably the adiponitrlle ls treated in the presence of water In a preferred embodiment the adiponitri~e is treated : in the presence Or both water ~nd a water-soluble acidlc compound especially phosphoric or acetic acid, If treated ln the presence o~ water, it is preferred~ for economic reasons that there are not more than two parts water per one part of adipon~trile, on a weight basis Preferably, the adlponitrile contains 1 to 10~ by weight of waterO
The process of the present lnvention may be carried out at temperatures in the range 20-100C. Treatment may occur at lower temperatures at low ratesO At higher temperatures, especially above 140C and in the presence of water, hydrolysis of 2-cyanocyclopentylideneimine~ which ma~ be present in the ;. crude adiponitrile, may occur. Such hydrol~sis of 2-cyanocyclopentylideneimine is disclosed in the aforementioned Canadian Patent 912,036O
: The pressure used.in the process of the present 20 inventlon is not critlcalO The pressure will depend primarily .:
on other process variables, for example, the temperature at wh~ch the process is operatedO
After operating the process for a period of time it may be desirable or necessary to replace and/or regenerate the boron phosphate or bentoniteO To regenerate used boron phos-: phate or bentonite, the boron pho3phate or bentonite may be heated under an atmosphere of lnert gas, treated with st~am at high temperatures or treated with a base of hlgher af~inity for the boron phosphate or bentonite ~ollowed by treatment to remove ~he baseO For example, the boron phosphate or bentonite may be contacted with an ammonia solution at a temperature of ~rom ambient to about 70C, separated there~rom and heated to remove ammoniaO
4~
Adiponitrile purified by the process de~cribed herein is partlcularly useful in the manufacture of hexamethylene dlamine uslng an lron catalyst as i8 disclosed in Canadian patent application 234 356 o~ B.J. Kers~aw ~iled on the same date as the present applicationv The invention is illustrated by the ~ollowing examples:
EXAMPLE I
To 25 ml of a crude adiponltrile manufactured from adipic acid and ammonla and containing approximately 300 ppm MAP, 700 ppm ABP and essentially 0% water was added approx-imately one gram of bentonite~ The mixture was ~tirred ~or 10 minutes at room temperature and then analyzed by gas chromato-graphyO Approximately 25% of the MAP and 24~ of the ABP had been removed ~rom the crude adiponitrlle, EXAMPLE II
2 ml of water was added to the above mixture. The resultant mixture was st~rred for a further 25 minutes at room temperature and re-analyzedO Approxim~tely 61~ of the MAP and 51% of the ABP had been removed from the crude adiponitrile.
EXAMPLE III
To 25 ml of a crude adiponitrile manufactured ~rom adipic acid and ammonia and contalning approximately 1200 ppm o~ MAP was added 2 ml of water and approximately one gram of bentonite. The mixture was stirred ~or 10 minutes ~t room temperature and then analyzed by gas chromatography. Approx~
imately 54% o~ the MAP had been removed ~rom the crude adipo-nitrile.
0~1 ml of 85% phosphoric acid was added to the abo~e mlxture. The resu~t~nt mixture was stirred for a further 30 min-; ~ I
utes at room temper~tureO Analysis showed that 100% o~ the MAP had ~een removed from the crude adiponitrile.
The bentonite was separated from the treated adipo-nitrile. me bentonite was placed in a filter and 25 ml of
Adiponitrile purified by the process de~cribed herein is partlcularly useful in the manufacture of hexamethylene dlamine uslng an lron catalyst as i8 disclosed in Canadian patent application 234 356 o~ B.J. Kers~aw ~iled on the same date as the present applicationv The invention is illustrated by the ~ollowing examples:
EXAMPLE I
To 25 ml of a crude adiponltrile manufactured from adipic acid and ammonla and containing approximately 300 ppm MAP, 700 ppm ABP and essentially 0% water was added approx-imately one gram of bentonite~ The mixture was ~tirred ~or 10 minutes at room temperature and then analyzed by gas chromato-graphyO Approximately 25% of the MAP and 24~ of the ABP had been removed ~rom the crude adiponitrlle, EXAMPLE II
2 ml of water was added to the above mixture. The resultant mixture was st~rred for a further 25 minutes at room temperature and re-analyzedO Approxim~tely 61~ of the MAP and 51% of the ABP had been removed from the crude adiponitrile.
EXAMPLE III
To 25 ml of a crude adiponitrile manufactured ~rom adipic acid and ammonia and contalning approximately 1200 ppm o~ MAP was added 2 ml of water and approximately one gram of bentonite. The mixture was stirred ~or 10 minutes ~t room temperature and then analyzed by gas chromatography. Approx~
imately 54% o~ the MAP had been removed ~rom the crude adipo-nitrile.
0~1 ml of 85% phosphoric acid was added to the abo~e mlxture. The resu~t~nt mixture was stirred for a further 30 min-; ~ I
utes at room temper~tureO Analysis showed that 100% o~ the MAP had ~een removed from the crude adiponitrile.
The bentonite was separated from the treated adipo-nitrile. me bentonite was placed in a filter and 25 ml of
5 -:~
"~ , ' ,, ' ' . , ' . ,:
~ ~ ~ 2~ ~
3~6 ammonium hydroxide solutlon was slowly pass0d through the bentonite. At least 50% o~ the MAP on the bentonite p&s~ed into the ~olution.
EXAMPLE IV
To 25 ml of a crude adiponltrile manufactured from adipic acid ~nd ammonia and containing approximately 300 ppm of MAP and ~pproximately 700 ppm o~ ABP was added 2 ml o~ water and 0.074 g of boron phosphate, The mixture was stlrred ~or 25 mlnutes at room temperature and then analyzed. Approxim-ately 37~ o~ ~he MAP and 73% o~ the ABP had been removed fromthe crude adiponitrile.
The boron phosphate used above was washed with dilute ammonium hydroxide at room temperature, Subsequent analysis showed that this washing almost quantitatively removed the MAP ~rom the boron phosphate.
:
., "
"~ , ' ,, ' ' . , ' . ,:
~ ~ ~ 2~ ~
3~6 ammonium hydroxide solutlon was slowly pass0d through the bentonite. At least 50% o~ the MAP on the bentonite p&s~ed into the ~olution.
EXAMPLE IV
To 25 ml of a crude adiponltrile manufactured from adipic acid ~nd ammonia and containing approximately 300 ppm of MAP and ~pproximately 700 ppm o~ ABP was added 2 ml o~ water and 0.074 g of boron phosphate, The mixture was stlrred ~or 25 mlnutes at room temperature and then analyzed. Approxim-ately 37~ o~ ~he MAP and 73% o~ the ABP had been removed fromthe crude adiponitrile.
The boron phosphate used above was washed with dilute ammonium hydroxide at room temperature, Subsequent analysis showed that this washing almost quantitatively removed the MAP ~rom the boron phosphate.
:
., "
Claims (11)
1. A process for reducing the amount of basic impurities in crude adiponitrile, said process comprising the steps of contacting crude adiponitrile with material selected from the group consisting of boron phosphate and bentonite, and mixtures thereof, at a temperature in the range 20-100°C.
2. The process of Claim 1 in which the adiponitrile is treated substantially in the absence of ammonia.
3. The process of Claim 2 in which the crude adipo-nitrile is treated with said material in the absence of water.
4. The process of Claim 2 in which the crude adipo-nitrile is adiponitrile manufactured from adipic acid and ammonia.
5. The process of Claim 4 in which the crude adipo-nitrile is treated with said material in the presence of water.
6. The process of Claim 5 in which the water contains a water-soluble acidic compound.
7. The process of Claim 6 in which the water-soluble acidic compound is selected from the group consisting of phosphoric acid and acetic acid.
8. The process of any one of Claim 3, Claim 5 and Claim 7 in which the ratio of water to adiponitrile is less than 2:1.
9. The process of any one of Claim 3, Claim 5 and Claim 7 in which the adiponitrile contains 1 to 10% water.
10. The process of any one of Claim 3, Claim 5 and Claim 6 in which the material is bentonite.
11. The process of any one of Claim 3, Claim 5 and Claim 6 in which the material is boron phosphate.
Priority Applications (9)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA000234358A CA1042464A (en) | 1975-08-26 | 1975-08-26 | Treatment of adiponitrile with boron phosphate or bentonite |
| IT2584376A IT1065070B (en) | 1975-08-26 | 1976-07-29 | PROCESS FOR THE PRODUCTION OF HEXAMETHYLENE DIAMINE |
| GB2643977A GB1539438A (en) | 1975-08-26 | 1976-08-17 | Process of purifying adiponitrile |
| GB3427076A GB1539435A (en) | 1975-08-26 | 1976-08-17 | Process for the manufacture of hexamethylene diamine |
| FR7625712A FR2322127A1 (en) | 1975-08-26 | 1976-08-25 | PERFECTED PROCESS FOR THE PRODUCTION OF HEXAMETHYLENE DIAMINE FROM CRUDE ADIPONITRILE |
| DE19762638510 DE2638510A1 (en) | 1975-08-26 | 1976-08-26 | IMPROVED PROCESS FOR THE PREPARATION OF HEXAMETHYLENEDIAMINE |
| FR7706940A FR2334664A1 (en) | 1975-08-26 | 1977-03-09 | METHOD FOR REDUCING THE QUANTITY OF N-HETEROCYCLIC AMINE IN CRUDE ADIPONITRILE |
| US05/858,661 US4146555A (en) | 1975-08-26 | 1977-12-08 | Process for purifying adiponitrile |
| US05/858,663 US4147717A (en) | 1975-08-26 | 1977-12-08 | Process for purifying adiponitrile |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA000234358A CA1042464A (en) | 1975-08-26 | 1975-08-26 | Treatment of adiponitrile with boron phosphate or bentonite |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1042464A true CA1042464A (en) | 1978-11-14 |
Family
ID=4103916
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000234358A Expired CA1042464A (en) | 1975-08-26 | 1975-08-26 | Treatment of adiponitrile with boron phosphate or bentonite |
Country Status (2)
| Country | Link |
|---|---|
| CA (1) | CA1042464A (en) |
| GB (1) | GB1539438A (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP4097077A1 (en) * | 2020-01-31 | 2022-12-07 | INVISTA Textiles (U.K.) Limited | Impurity formation reduction during product refining |
-
1975
- 1975-08-26 CA CA000234358A patent/CA1042464A/en not_active Expired
-
1976
- 1976-08-17 GB GB2643977A patent/GB1539438A/en not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| GB1539438A (en) | 1979-01-31 |
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