DE1279020B - Process for the continuous production of aliphatic or aromatic nitriles from carboxylic acid esters - Google Patents
Process for the continuous production of aliphatic or aromatic nitriles from carboxylic acid estersInfo
- Publication number
- DE1279020B DE1279020B DEF49870A DEF0049870A DE1279020B DE 1279020 B DE1279020 B DE 1279020B DE F49870 A DEF49870 A DE F49870A DE F0049870 A DEF0049870 A DE F0049870A DE 1279020 B DE1279020 B DE 1279020B
- Authority
- DE
- Germany
- Prior art keywords
- aliphatic
- continuous production
- carboxylic acid
- acid esters
- aromatic nitriles
- 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.)
- Pending
Links
- -1 aromatic nitriles Chemical class 0.000 title claims description 7
- 238000000034 method Methods 0.000 title claims description 7
- 125000001931 aliphatic group Chemical group 0.000 title claims description 4
- 238000010924 continuous production Methods 0.000 title claims description 4
- 150000001733 carboxylic acid esters Chemical class 0.000 title description 2
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 claims description 18
- 150000002148 esters Chemical class 0.000 claims description 10
- 229910021529 ammonia Inorganic materials 0.000 claims description 9
- WOZVHXUHUFLZGK-UHFFFAOYSA-N dimethyl terephthalate Chemical compound COC(=O)C1=CC=C(C(=O)OC)C=C1 WOZVHXUHUFLZGK-UHFFFAOYSA-N 0.000 claims description 4
- 235000014113 dietary fatty acids Nutrition 0.000 claims description 3
- 229930195729 fatty acid Natural products 0.000 claims description 3
- 239000000194 fatty acid Substances 0.000 claims description 3
- 150000004665 fatty acids Chemical class 0.000 claims description 3
- 239000003054 catalyst Substances 0.000 claims description 2
- QSSJZLPUHJDYKF-UHFFFAOYSA-N methyl 4-methylbenzoate Chemical compound COC(=O)C1=CC=C(C)C=C1 QSSJZLPUHJDYKF-UHFFFAOYSA-N 0.000 claims 1
- 150000002825 nitriles Chemical class 0.000 description 10
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 7
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 6
- 239000007789 gas Substances 0.000 description 5
- 238000000926 separation method Methods 0.000 description 5
- VCZNNAKNUVJVGX-UHFFFAOYSA-N 4-methylbenzonitrile Chemical compound CC1=CC=C(C#N)C=C1 VCZNNAKNUVJVGX-UHFFFAOYSA-N 0.000 description 4
- BHXFKXOIODIUJO-UHFFFAOYSA-N benzene-1,4-dicarbonitrile Chemical compound N#CC1=CC=C(C#N)C=C1 BHXFKXOIODIUJO-UHFFFAOYSA-N 0.000 description 3
- 150000001735 carboxylic acids Chemical class 0.000 description 3
- 239000013078 crystal Substances 0.000 description 3
- 239000007788 liquid Substances 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- 239000000047 product Substances 0.000 description 3
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 2
- URLKBWYHVLBVBO-UHFFFAOYSA-N Para-Xylene Chemical group CC1=CC=C(C)C=C1 URLKBWYHVLBVBO-UHFFFAOYSA-N 0.000 description 2
- KKEYFWRCBNTPAC-UHFFFAOYSA-N Terephthalic acid Chemical compound OC(=O)C1=CC=C(C(O)=O)C=C1 KKEYFWRCBNTPAC-UHFFFAOYSA-N 0.000 description 2
- 239000007795 chemical reaction product Substances 0.000 description 2
- 238000001816 cooling Methods 0.000 description 2
- 239000003925 fat Substances 0.000 description 2
- 235000019197 fats Nutrition 0.000 description 2
- 238000002844 melting Methods 0.000 description 2
- 230000008018 melting Effects 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- TWNQGVIAIRXVLR-UHFFFAOYSA-N oxo(oxoalumanyloxy)alumane Chemical compound O=[Al]O[Al]=O TWNQGVIAIRXVLR-UHFFFAOYSA-N 0.000 description 2
- LPNBBFKOUUSUDB-UHFFFAOYSA-N p-toluic acid Chemical compound CC1=CC=C(C(O)=O)C=C1 LPNBBFKOUUSUDB-UHFFFAOYSA-N 0.000 description 2
- 239000007858 starting material Substances 0.000 description 2
- NWPNXBQSRGKSJB-UHFFFAOYSA-N 2-methylbenzonitrile Chemical compound CC1=CC=CC=C1C#N NWPNXBQSRGKSJB-UHFFFAOYSA-N 0.000 description 1
- ISKQADXMHQSTHK-UHFFFAOYSA-N [4-(aminomethyl)phenyl]methanamine Chemical compound NCC1=CC=C(CN)C=C1 ISKQADXMHQSTHK-UHFFFAOYSA-N 0.000 description 1
- 150000001408 amides Chemical class 0.000 description 1
- 150000001412 amines Chemical class 0.000 description 1
- 238000009835 boiling Methods 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 238000003776 cleavage reaction Methods 0.000 description 1
- 235000019864 coconut oil Nutrition 0.000 description 1
- 239000003240 coconut oil Substances 0.000 description 1
- 239000012043 crude product Substances 0.000 description 1
- 239000000428 dust Substances 0.000 description 1
- 239000003822 epoxy resin Substances 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- LNEPOXFFQSENCJ-UHFFFAOYSA-N haloperidol Chemical compound C1CC(O)(C=2C=CC(Cl)=CC=2)CCN1CCCC(=O)C1=CC=C(F)C=C1 LNEPOXFFQSENCJ-UHFFFAOYSA-N 0.000 description 1
- 238000007654 immersion Methods 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 239000000543 intermediate Substances 0.000 description 1
- WVWZECQNFWFVFW-UHFFFAOYSA-N methyl 2-methylbenzoate Chemical compound COC(=O)C1=CC=CC=C1C WVWZECQNFWFVFW-UHFFFAOYSA-N 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- ZWLPBLYKEWSWPD-UHFFFAOYSA-N o-toluic acid Chemical compound CC1=CC=CC=C1C(O)=O ZWLPBLYKEWSWPD-UHFFFAOYSA-N 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 229920000647 polyepoxide Polymers 0.000 description 1
- 239000004848 polyfunctional curative Substances 0.000 description 1
- 238000010926 purge Methods 0.000 description 1
- 230000007017 scission Effects 0.000 description 1
- 238000003860 storage Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- MHSKRLJMQQNJNC-UHFFFAOYSA-N terephthalamide Chemical compound NC(=O)C1=CC=C(C(N)=O)C=C1 MHSKRLJMQQNJNC-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C253/00—Preparation of carboxylic acid nitriles
- C07C253/22—Preparation of carboxylic acid nitriles by reaction of ammonia with carboxylic acids with replacement of carboxyl groups by cyano groups
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Description
Verfahren zur kontinuierlichen Herstellung von aliphatischen oder aromatischen Nitrilen aus Carbonsäureestern Es ist allgemein bekannt, daß man Nitrile durch Umsetzen der entsprechenden Carbonsäuren mit Ammoniak in der Gasphase an dehydratisierenden Kontakten herstellen kann. In vielen Fällen stehen aber als Ausgangsmaterialien nur Gemische von Carbonsäuren zur Verfügung - wie sie beispielsweise bei der Oxydation von p-Xylol in Form von p-Toluylsäure und Terephthalsäure anfallen -, deren Trennung technisch über ihre Ester vorgenommen wird.Process for the continuous production of aliphatic or aromatic nitriles from carboxylic acid esters It is generally known that nitriles dehydrating by reacting the corresponding carboxylic acids with ammonia in the gas phase Can establish contacts. In many cases, however, are available as starting materials only mixtures of carboxylic acids are available - as they are, for example, in the case of oxidation of p-xylene in the form of p-toluic acid and terephthalic acid - their separation is made technically via their esters.
Für die Herstellung ihrer Nitrile ist es daher wünschenswert, direkt von den Estern auszugehen.It is therefore desirable for the production of their nitriles directly to start from the esters.
Gegenstand der Erfindung ist ein Verfahren zur kontinuierlichen Herstellung von aliphatischen oder aromatischen Nitrilen, welches dadurch gekennzeichnet ist, daß man Ester von Fettsäuren oder von aromatischen Carbonsäuren mit Ammoniak in der Gasphase an dehydratisierenden Katalysatoren bei einer Temperatur von 340 bis 360"C umsetzt. The invention relates to a process for continuous production of aliphatic or aromatic nitriles, which is characterized by that one esters of fatty acids or of aromatic carboxylic acids with ammonia in the gas phase over dehydrating catalysts at a temperature of 340 to 360 "C converts.
Die gebildeten Nitrile werden aus der Gasphase durch Abkühlen in flüssiger bzw. kristallisierter Form neben den Spaltprodukten Alkohol und Wasser abgeschieden und das überschüssige Ammoniak im Kreislauf zurückgeführt. The nitriles formed are removed from the gas phase by cooling in liquid or crystallized form in addition to the cleavage products alcohol and water separated and the excess ammonia returned in the cycle.
Das Verfahren eignet sich insbesondere für die Herstellung von p-Tolunitril oder Terephthalsäuredinitril aus den technisch leicht zugänglichen Carbonsäuremethylestern. Selbstverständlich können auch Ester anderer Carbonsäuren - nämlich die Ester von Fettsäuren, wie sie in den natürlichen Fetten vorliegen - auf diese Weise in Nitrile übergeführt werden. The process is particularly suitable for the production of p-tolunitrile or terephthalic acid dinitrile from the technically easily accessible carboxylic acid methyl esters. Of course, esters of other carboxylic acids - namely the esters of Fatty acids as found in natural fats - in this way in nitriles be transferred.
Das Verfahren der Erfindung soll an Hand des Schemas und der nachfolgenden Beispiele erläutert werden. The method of the invention is intended to be based on the scheme and the following Examples are explained.
Aus einem mit Dampf heizbaren Vorratsbehälter 1 wird der Ester mittels der Dosierpumpe 2 in den Erhitzer 3 gedrückt. Der verdampfte Ester gelangt mit dem aus dem Kreisprozeß zurückgeführten Ammoniak in den Kontaktofen 4, wo die Umsetzung zu Nitril, Alkohol und Wasser stattfindet. Ist das anfallende Nitril bei Raumtemperatur flüssig, wie Tolunitril, so genügt ein Wasserkühler zur Abscheidung der Reaktionsprodukte. Im anderen Falle, wie bei Terephthalodinitril vom Schmelzpunkt 225°C gelangt der Kreis strom in zwei hintereinandergeschaltete Abscheider 5 und 6, in denen sich die Kristalle absetzen. Die Abkühlung des Kreisgases erfolgt im ersten Abscheider durch Einspritzen einer solchen Menge Wasser, daß dieses noch ganz verdampft und das Produkt möglichst trocken anfällt. Zwecks Ausräumung des Nitrils sind die Produktabscheider 5 und 6 doppelt vorhanden, um die Produktion nicht unterbrechen zu müssen. Nach den Abscheidern passiert das Ammoniak noch eine Wassertauchung 7, welche mitgerissenen Kristallstaub zurückhält. Anschließend kehrt das Ammoniak mit dem frisch zugeführten Anteil über das Gebläse 9 und den Erhitzer 11 in den Kreislauf zurück. Auf der Saug- und Druckseite des Gebläses befinden sich die Windkessel 8 und 10. The ester is obtained from a storage container 1 which can be heated with steam the dosing pump 2 is pressed into the heater 3. The vaporized ester arrives with the ammonia recycled from the cycle into the contact furnace 4, where the implementation to nitrile, alcohol and water takes place. Is the resulting nitrile at room temperature liquid, such as tolunitrile, a water cooler is sufficient to separate the reaction products. In the other case, as in the case of terephthalodinitrile with a melting point of 225 ° C., the Circulating current in two series-connected separators 5 and 6, in which the crystals settle. The cycle gas is cooled in the first separator by injecting such an amount of water that it evaporates completely and the product is as dry as possible. The product separators are used to remove the nitrile 5 and 6 are duplicated to prevent production having to interrupt. After the The ammonia also passes through a water immersion 7 separators, which are carried away Retains crystal dust. Subsequently, the ammonia returns with the freshly supplied Share via the fan 9 and the heater 11 back into the circuit. On the suction and pressure side of the fan are the air chambers 8 and 10.
Die günstigsten Reaktionstemperaturen liegen zwischen 340 und 360"C. Die Ausbeute an Nitril beträgt 90 bis 95°/0 der Theorie. Der Rest besteht aus Säureamid, welches nach Abtrennung gegebenenfalls wieder in den Kreislauf zurückgeführt werden kann. The most favorable reaction temperatures are between 340 and 360.degree. The nitrile yield is 90 to 95% of theory. The rest consists of acid amide, which may be returned to the cycle after separation can.
Die erhaltenen Nitrile dienen in erster Linie als Zwischenprodukte. p-Tolunitril wird als Ausgangsprodukt für optische Aufheller verwendet. Terephthalsäuredinitril kann beispielsweise zu p-Xylylendiamin bzw. zu 1,4- [Aminomethyl]-cyclohexan hydriert werden. Beide Substanzen sind gute Aminhärter für Epoxyharze. The nitriles obtained serve primarily as intermediates. p-Tolunitrile is used as a starting material for optical brighteners. Terephthalic acid dinitrile can, for example, be hydrogenated to p-xylylenediamine or to 1,4- [aminomethyl] cyclohexane will. Both substances are good amine hardeners for epoxy resins.
Beispiel 1 Über 2001 Aluminiumoxyd werden bei 340"C stündlich etwa 17 kg Toluylsäuremethylester im Ammoniakstrom geleitet. Die Reaktionsprodukte p-Tolunitril, Methanol und Wasser werden kondensiert und in einem Behälter gesammelt. Nach Abtrennung der wäßrigen Schicht wird durch Destillation p-Tolunitril mit einem Reinheitsgrad von 99,8 0/o erhalten. Example 1 About 2001 aluminum oxide will be at 340 "C approximately every hour 17 kg of methyl toluate passed in a stream of ammonia. The reaction products p-tolunitrile, Methanol and water are condensed and collected in a container. After separation the aqueous layer is distilled to p-tolunitrile with a degree of purity of 99.8% obtained.
Die Ausbeute beträgt etwa 950/o der Theorie. Das als Rückstand verbleibende Toluylsäureamid kann wieder verwendet werden.The yield is about 950% of theory. That remaining as residue Toluic acid amide can be reused.
Beispiel 2 Über die gleiche Menge Kontakt leitet man stündlich 5 bis 6 kg Terephthalsäuredimethylester bei 350 bis 360"C. Der aus dem Kontaktofen entweichende Gasstrom wird durch Einspritzen von Wasser auf etwa 130"C abgeschreckt, worauf sich das Dinitril in den Abscheidekammern in Form von Kristallen absetzt. Der Durchsatz an Ester richtet sich nach der Größe der Abscheidekammern. Sobald diese genügend gefüllt sind, wird auf die Reserveabscheider umgeschaltet. Nach dem Spülen mit Stickstoff und Abkühlen wird das Dinitril durch ein Mannloch am Boden der Abscheider mechanisch entleert. Das noch etwas feuchte Rohprodukt wird durch Auskochen mit Methanol gereinigt, wobei farbige Verunreinigungen und Terephthalsäurediamid entfernt werden. Example 2 The same amount of contact is passed every hour 5 up to 6 kg of dimethyl terephthalate at 350 to 360 "C. The one from the contact furnace escaping Gas flow is made by injecting water at about 130 "C quenched, whereupon the dinitrile in the separation chambers in the form of Crystals settle. The throughput of ester depends on the size of the separation chambers. As soon as these are sufficiently filled, a switch is made to the reserve separator. After purging with nitrogen and cooling, the dinitrile is released through a manhole The separator is mechanically emptied at the bottom. The crude product is still slightly moist Purified by boiling with methanol, leaving colored impurities and terephthalic acid diamide removed.
Danach hat das Dinitril einen Schmelzpunkt von etwa 220 bis 222"C und kann für die meisten Zwecke verwendet werden. Die Ausbeute beträgt 95 bis 970/o der Theorie.Thereafter, the dinitrile has a melting point of about 220 to 222 "C and can be used for most purposes. The yield is 95 to 970% the theory.
Beispiel 3 Auf 300 ccm Aluminiumoxyd läßt man bei einer Temperatur von 350 bis 360"C im Ammoniakstrom stündlich etwa 50 ccm flüssiges Cocosfett tropfen. Example 3 300 cc of aluminum oxide is left at one temperature from 350 to 360 "C in the ammonia stream Drip about 50 ccm of liquid coconut oil every hour.
Nach 6 Stunden waren 300 ccm = 268 g Fett durchgesetzt. Vom Kondensat wurde die wäßrige Schicht abgetrennt und das Nitrilgemisch bei einem Druck von 1,3 Torr destilliert, wobei 196 g zwischen 60 bis 1900C (Hauptanteil 110 bis 140"C) übergingen.After 6 hours, 300 ccm = 268 g of fat had passed through. From the condensate the aqueous layer was separated and the nitrile mixture at a pressure of 1.3 Torr distilled, with 196 g between 60 to 1900C (main portion 110 to 140 "C) passed over.
Claims (2)
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DEF49870A DE1279020B (en) | 1966-08-04 | 1966-08-04 | Process for the continuous production of aliphatic or aromatic nitriles from carboxylic acid esters |
| BE702294D BE702294A (en) | 1966-08-04 | 1967-08-04 |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DEF49870A DE1279020B (en) | 1966-08-04 | 1966-08-04 | Process for the continuous production of aliphatic or aromatic nitriles from carboxylic acid esters |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| DE1279020B true DE1279020B (en) | 1968-10-03 |
Family
ID=7103340
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| DEF49870A Pending DE1279020B (en) | 1966-08-04 | 1966-08-04 | Process for the continuous production of aliphatic or aromatic nitriles from carboxylic acid esters |
Country Status (2)
| Country | Link |
|---|---|
| BE (1) | BE702294A (en) |
| DE (1) | DE1279020B (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4806672A (en) * | 1987-02-25 | 1989-02-21 | Caffaro S.P.A. Societa Per L'industria Chimica Ed Electtrochimica | Process for the continuous production of isophthalodinitrile |
| WO1991001298A1 (en) * | 1989-07-20 | 1991-02-07 | MERCK Patent Gesellschaft mit beschränkter Haftung | Process for the preparation of aromatic nitriles |
| DE19520491A1 (en) * | 1995-06-03 | 1996-12-05 | Sueddeutsche Kalkstickstoff | Process for the preparation of amino and hydroxybenzonitriles |
| US11673856B2 (en) | 2018-07-27 | 2023-06-13 | Mitsubishi Gas Chemical Company, Inc. | Method for producing aromatic nitrile compound and method for producing carbonate ester |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| IT1188652B (en) * | 1986-04-14 | 1988-01-20 | Caffaro Spa Ind Chim | PROCEDURE FOR THE CONTINUOUS PRODUCTION OF PHTHALODYNITRILE |
-
1966
- 1966-08-04 DE DEF49870A patent/DE1279020B/en active Pending
-
1967
- 1967-08-04 BE BE702294D patent/BE702294A/xx unknown
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4806672A (en) * | 1987-02-25 | 1989-02-21 | Caffaro S.P.A. Societa Per L'industria Chimica Ed Electtrochimica | Process for the continuous production of isophthalodinitrile |
| WO1991001298A1 (en) * | 1989-07-20 | 1991-02-07 | MERCK Patent Gesellschaft mit beschränkter Haftung | Process for the preparation of aromatic nitriles |
| DE19520491A1 (en) * | 1995-06-03 | 1996-12-05 | Sueddeutsche Kalkstickstoff | Process for the preparation of amino and hydroxybenzonitriles |
| US11673856B2 (en) | 2018-07-27 | 2023-06-13 | Mitsubishi Gas Chemical Company, Inc. | Method for producing aromatic nitrile compound and method for producing carbonate ester |
| US12202786B2 (en) | 2018-07-27 | 2025-01-21 | Mitsubishi Gas Chemical Company, Inc. | Method for producing aromatic nitrile compound and method for producing carbonate ester |
Also Published As
| Publication number | Publication date |
|---|---|
| BE702294A (en) | 1968-02-05 |
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