NO892590L - PROCEDURE FOR THE PREPARATION OF VINYL ACETATE. - Google Patents
PROCEDURE FOR THE PREPARATION OF VINYL ACETATE.Info
- Publication number
- NO892590L NO892590L NO89892590A NO892590A NO892590L NO 892590 L NO892590 L NO 892590L NO 89892590 A NO89892590 A NO 89892590A NO 892590 A NO892590 A NO 892590A NO 892590 L NO892590 L NO 892590L
- Authority
- NO
- Norway
- Prior art keywords
- cleavage
- vinyl acetate
- stated
- reaction
- ketene
- Prior art date
Links
- 238000000034 method Methods 0.000 title claims description 14
- XTXRWKRVRITETP-UHFFFAOYSA-N Vinyl acetate Chemical compound CC(=O)OC=C XTXRWKRVRITETP-UHFFFAOYSA-N 0.000 title claims description 13
- WFDIJRYMOXRFFG-UHFFFAOYSA-N Acetic anhydride Chemical compound CC(=O)OC(C)=O WFDIJRYMOXRFFG-UHFFFAOYSA-N 0.000 claims description 30
- 238000003776 cleavage reaction Methods 0.000 claims description 14
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 claims description 12
- JTXMVXSTHSMVQF-UHFFFAOYSA-N 2-acetyloxyethyl acetate Chemical compound CC(=O)OCCOC(C)=O JTXMVXSTHSMVQF-UHFFFAOYSA-N 0.000 claims description 11
- 239000003054 catalyst Substances 0.000 claims description 11
- 238000004519 manufacturing process Methods 0.000 claims description 11
- CCGKOQOJPYTBIH-UHFFFAOYSA-N ethenone Chemical compound C=C=O CCGKOQOJPYTBIH-UHFFFAOYSA-N 0.000 claims description 9
- 230000007017 scission Effects 0.000 claims description 9
- 230000002378 acidificating effect Effects 0.000 claims description 4
- 239000011541 reaction mixture Substances 0.000 claims description 4
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 description 33
- 238000006243 chemical reaction Methods 0.000 description 9
- IKHGUXGNUITLKF-UHFFFAOYSA-N Acetaldehyde Chemical compound CC=O IKHGUXGNUITLKF-UHFFFAOYSA-N 0.000 description 8
- 230000015572 biosynthetic process Effects 0.000 description 4
- 238000002474 experimental method Methods 0.000 description 3
- 239000012071 phase Substances 0.000 description 3
- GOKCJCODOLGYQD-UHFFFAOYSA-N 4,6-dichloro-2-imidazol-1-ylpyrimidine Chemical compound ClC1=CC(Cl)=NC(N2C=NC=C2)=N1 GOKCJCODOLGYQD-UHFFFAOYSA-N 0.000 description 2
- 239000003377 acid catalyst Substances 0.000 description 2
- 125000003118 aryl group Chemical group 0.000 description 2
- 238000004821 distillation Methods 0.000 description 2
- 238000003756 stirring Methods 0.000 description 2
- BDHFUVZGWQCTTF-UHFFFAOYSA-N sulfonic acid Chemical compound OS(=O)=O BDHFUVZGWQCTTF-UHFFFAOYSA-N 0.000 description 2
- 238000003786 synthesis reaction Methods 0.000 description 2
- LBLYYCQCTBFVLH-UHFFFAOYSA-N 2-Methylbenzenesulfonic acid Chemical compound CC1=CC=CC=C1S(O)(=O)=O LBLYYCQCTBFVLH-UHFFFAOYSA-N 0.000 description 1
- 229910015900 BF3 Inorganic materials 0.000 description 1
- 238000005727 Friedel-Crafts reaction Methods 0.000 description 1
- 239000004372 Polyvinyl alcohol Substances 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 150000007513 acids Chemical class 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- SRSXLGNVWSONIS-UHFFFAOYSA-N benzenesulfonic acid Chemical compound OS(=O)(=O)C1=CC=CC=C1 SRSXLGNVWSONIS-UHFFFAOYSA-N 0.000 description 1
- WTEOIRVLGSZEPR-UHFFFAOYSA-N boron trifluoride Chemical compound FB(F)F WTEOIRVLGSZEPR-UHFFFAOYSA-N 0.000 description 1
- 230000015556 catabolic process Effects 0.000 description 1
- 238000004587 chromatography analysis Methods 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 238000006731 degradation reaction Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000007717 exclusion Effects 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 229920001519 homopolymer Polymers 0.000 description 1
- 239000007791 liquid phase Substances 0.000 description 1
- PSZYNBSKGUBXEH-UHFFFAOYSA-N naphthalene-1-sulfonic acid Chemical compound C1=CC=C2C(S(=O)(=O)O)=CC=CC2=C1 PSZYNBSKGUBXEH-UHFFFAOYSA-N 0.000 description 1
- 238000006116 polymerization reaction Methods 0.000 description 1
- 229920002689 polyvinyl acetate Polymers 0.000 description 1
- 239000011118 polyvinyl acetate Substances 0.000 description 1
- 229920002451 polyvinyl alcohol Polymers 0.000 description 1
- 230000035484 reaction time Effects 0.000 description 1
- 238000011084 recovery Methods 0.000 description 1
- 238000010992 reflux Methods 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C57/00—Unsaturated compounds having carboxyl groups bound to acyclic carbon atoms
- C07C57/02—Unsaturated compounds having carboxyl groups bound to acyclic carbon atoms with only carbon-to-carbon double bonds as unsaturation
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C67/00—Preparation of carboxylic acid esters
- C07C67/28—Preparation of carboxylic acid esters by modifying the hydroxylic moiety of the ester, such modification not being an introduction of an ester group
- C07C67/297—Preparation of carboxylic acid esters by modifying the hydroxylic moiety of the ester, such modification not being an introduction of an ester group by splitting-off hydrogen or functional groups; by hydrogenolysis of functional groups
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)
- Medicinal Preparation (AREA)
Description
Foreliggende oppfinnelse vedrører fremstilling av vinylacetat ved spaltning av etylidendiacetat (EDA). The present invention relates to the production of vinyl acetate by splitting ethylene diacetate (EDA).
Vinylacetat er et kjemisk produkt som i mange år har hatt stor industriell betydning, og store mengder anvendes særlig for fremstilling av homopolymerer som polyvinylacetat og polyvinylalkohol. Vinyl acetate is a chemical product that has had great industrial importance for many years, and large quantities are used in particular for the production of homopolymers such as polyvinyl acetate and polyvinyl alcohol.
Syntese av monovinylacetat (MVAC) ved spaltning av EDA er en reaksjon som har vært kjent i lang tid. Tallrike problemer opptrer ved denne syntese, særlig på grunn av at EDA har tendens til å spalte seg særlig i to hovedretninger, nemlig samtidig fremstilling av monovinylacetat og eddiksyre eller samtidig fremstilling av acetaldehyd og eddiksyreanhydrid. Synthesis of monovinyl acetate (MVAC) by cleavage of EDA is a reaction that has been known for a long time. Numerous problems arise with this synthesis, particularly because EDA tends to split in particular in two main directions, namely the simultaneous production of monovinyl acetate and acetic acid or the simultaneous production of acetaldehyde and acetic anhydride.
I US patentskrift nr. 2.425.389 er det foreslått å spalte EDA i et overskudd av eddiksyreanhydrid i nærvær av en aromatisk sulfonsyre som katalysator og fjerne monovinylacetat og eddiksyre ved destillasjon etter hvert og i den grad de dannes for å begunstige forløpet av den ønskede reaksjon og begrense faren for polymerisering og/eller nedbrytning av monovinylacetatproduktet. In US Patent No. 2,425,389 it is proposed to cleave EDA in an excess of acetic anhydride in the presence of an aromatic sulphonic acid as a catalyst and to remove monovinyl acetate and acetic acid by distillation gradually and to the extent that they are formed to favor the course of the desired reaction and limiting the danger of polymerization and/or degradation of the monovinyl acetate product.
Det er likeledes velkjent at spaltningen av EDA til mono-; vinylacetat begunstiges ved nærvær av et stort overskudd av eddiksyreanhydrid. It is likewise well known that the cleavage of EDA into mono-; vinyl acetate is favored in the presence of a large excess of acetic anhydride.
Effektiviteten av de tidligere kjente prosesser er imidlertid ikke helt ut tilfredsstillende, idet spaltningsreaksjonen ofte hurtig blokkeres, og blir lite selektiv som påvist ved andelen av dannet acetaldehyd og alltid fulgt av en samtidig produksjon av eddiksyre som ganske riktig i og for seg er anvendelig, men eddiksyreproduksjon på denne måte er ikke særlig rasjonell. However, the efficiency of the previously known processes is not entirely satisfactory, as the cleavage reaction is often quickly blocked, and becomes unselective as demonstrated by the proportion of acetaldehyde formed and always followed by a simultaneous production of acetic acid, which quite correctly in and of itself is applicable, but acetic acid production in this way is not very rational.
Det er nå funnet at det er mulig å fremstille monovinylacetat ved spaltning av EDA under unngåelse av en samtidig produksjon av eddiksyre, med en forbedret selektivitet mens det riktige reaksjonsforløp med spaltning begunstiges i en tid som er mer forlikelig med produksjonskravene i industriell målestokk. It has now been found that it is possible to produce monovinyl acetate by cleavage of EDA while avoiding a simultaneous production of acetic acid, with an improved selectivity while favoring the correct reaction course with cleavage in a time that is more compatible with the production requirements on an industrial scale.
Foreliggende oppfinnelse vedrører således en fremgangsmåte for fremstilling av vinylacetat ved spaltning av etylidendiacetat under innvirkning av temperatur og en sur katalysator, eventuelt i nærvær av eddiksyreanhydrid, og det særegne ved fremgangsmåten i henhold til oppfinnelsen er at spaltningen gjennomføres med innføring av keten i reaksjonsblandingen. The present invention thus relates to a method for the production of vinyl acetate by splitting ethylidene diacetate under the influence of temperature and an acidic catalyst, possibly in the presence of acetic anhydride, and the peculiarity of the method according to the invention is that the splitting is carried out with the introduction of ketene into the reaction mixture.
Spaltningen frembringes under samtidig innvirkning av temperatur og en sur katalysator. The cleavage is produced under the simultaneous influence of temperature and an acidic catalyst.
Temperaturen er typisk mellom 60 og 200°C og foretrukket mellom 100 og 140°C. The temperature is typically between 60 and 200°C and preferably between 100 and 140°C.
Angjeldende reaksjon kan gjennomføres i flytende fase eller blandet fase under atmosfæretrykk eller autogent trykk. The reaction in question can be carried out in liquid phase or mixed phase under atmospheric pressure or autogenous pressure.
Med sur katalysator menes en hvilken som helst vanlig sur katalysator (understøttet eller ikke), f.eks. svovelsyre, sulfonsyre og særlig aromatiske sulfonsyrer som benzensul-fonsyre, toluensyre eller naftalensulfonsyre eller en katalysator av Friedel-Crafts typen som borfluorid. Svovelsyren egner seg særlig godt ved utførelsen av den foreliggende fremgangsmåten. • Acid catalyst means any common acid catalyst (supported or not), e.g. sulfuric acid, sulphonic acid and especially aromatic sulphonic acids such as benzene sulphonic acid, toluene sulphonic acid or naphthalene sulphonic acid or a catalyst of the Friedel-Crafts type such as boron fluoride. Sulfuric acid is particularly suitable for carrying out the present method. •
Mengden av katalysator som anvendes er ikke kritisk og det nøyaktige valg av mengden blir ofte for en gitt katalysator et kompromiss mellom den ønskede aktivitet og prisen og/eller vanskeligheten med håndtering av de innførte faser av sur katalysator. The amount of catalyst used is not critical and the exact choice of the amount often becomes for a given catalyst a compromise between the desired activity and the price and/or the difficulty of handling the introduced phases of acidic catalyst.
Med svovelsyre oppnås gode resultater med et katalysatorinn-hold på mellom 10 og 250 mmol/1 i reaksjonsblandingen. With sulfuric acid, good results are achieved with a catalyst content of between 10 and 250 mmol/1 in the reaction mixture.
Som de fagkyndige på dette område vet kan fremgangsmåten i henhold til oppfinnelsen selvfølgelig gjennomføres i store mengder eddiksyreanhydrid. As those skilled in this field know, the method according to the invention can of course be carried out in large quantities of acetic anhydride.
Innenfor rammen av den foreliggende oppfinnelse er det vesentlig at spaltningen gjennomføres med innføring av keten. Within the framework of the present invention, it is essential that the cleavage is carried out with the introduction of the ketene.
Det er faktisk fastslått at spaltningsreaksjonen gjennomført på denne måte skjer gunstigere ved samtidig å begrense den ikke ønskede spaltningsreaksjon til acetaldehyd og at den etterstrebede spaltningsreaksjon skal foregå i en lengre periode, uten at det iakttas særlig fall i produktiviteten. It has actually been established that the cleavage reaction carried out in this way takes place more favorably by simultaneously limiting the undesired cleavage reaction to acetaldehyde and that the sought-after cleavage reaction should take place for a longer period, without any particular drop in productivity being observed.
Innføringen av keten tillater fullstendig utelukkelse av den samtidige produksjon av eddiksyre og å lette separeringen og utvinningen av vinylacetatet. The introduction of the ketene allows the complete exclusion of the simultaneous production of acetic acid and to facilitate the separation and recovery of the vinyl acetate.
Innføringen av keten kan gjennomføres på flere måter. Således kan man innføre ketenet etter hvert og i ønsket mengde etter som spaltningsreaksjonen forløper eller også kontinuerlig, idet dette i praksis viser seg mest gunstig. The introduction of the chain can be carried out in several ways. Thus, the ketene can be introduced gradually and in the desired quantity as the cleavage reaction progresses or also continuously, as this proves to be the most beneficial in practice.
Mengden av keten kan selvfølgelig variere innen vide grenser og gode resultater oppnås når denne mengde, uttrykt som mol pr. time og pr. mol EDA som skal omdannes, er mellom 0,5 og 10 og foretrukket mellom 1 og 5. The amount of ketene can of course vary within wide limits and good results are achieved when this amount, expressed as moles per hour and per The moles of EDA to be converted are between 0.5 and 10 and preferably between 1 and 5.
Fremgangsmåten i henhold til oppfinnelsen kan gjennomføres diskontinuerlig eller kontinuerlig. Etter den tid som er ønskelig for reaksjon (eller en bestemt oppholdstid) separeres bestanddelene i reaksjonsblandingen ved hjelp av passende kjente midler, f.eks. ved destillasjon og man utvinner vinylacetatet. The method according to the invention can be carried out discontinuously or continuously. After the time desired for reaction (or a specific residence time), the components of the reaction mixture are separated by means of suitable known means, e.g. by distillation and the vinyl acetate is recovered.
De etterfølgende eksempler illustrerer oppfinnelsen: The following examples illustrate the invention:
Arbeidsmåte:Working method:
I en glassautoklav utstyrt med magnetisk røreverk og gasstilførsel, påsatt en Vigreux-kolonne på toppen og som er forbundet med gassfeller montert i serie, innføres en oppløsning av etylidendiacetat og svovelsyre i eddiksyreanhydrid. Omrøringen igangsettes og oppløsningen bringes til å holdes under tilbakeløp (140°C). Ketenet bringes deretter til koking i oppløsningen med konstant tilførsel. Etter den ønskede reaksjonstid stanses oppvarmingen, omrøringen og innføringen av gass. Produktene analyseres deretter ved gassfasekromatografering, idet acetaldehyd og eddiksyreanhydrid gjenfinnes i gassfellene anordnet etter reaktoren og at etylidendiacetatet, eddiksyreanhydridet og i det enkelte tilfelle eddiksyren befinner seg i spaltningsreaktoren. In a glass autoclave equipped with a magnetic stirrer and gas supply, fitted with a Vigreux column on top and connected to gas traps mounted in series, a solution of ethylene diacetate and sulfuric acid in acetic anhydride is introduced. Stirring is started and the solution is brought to reflux (140°C). The ketene is then brought to a boil in the solution with a constant feed. After the desired reaction time, the heating, stirring and introduction of gas are stopped. The products are then analyzed by gas phase chromatography, as acetaldehyde and acetic anhydride are found in the gas traps arranged after the reactor and that the ethylene diacetate, acetic anhydride and, in the individual case, the acetic acid are located in the cleavage reactor.
Eksempler 1 til 3. sammenligningsforsøk a:Examples 1 to 3. comparison experiment a:
Ved arbeidsmåten beskrevet i det foregående gjennomføres en rekke forsøk under anvendelse av forskjellige mengder keten for en tilførsel inneholdende: In the method described above, a series of experiments are carried out using different amounts of ketene for a supply containing:
5 0 mmol etylidendiacetat50 mmol ethylidene diacetate
5 3 mmol eddiksyreanhydrid og5 3 mmol acetic anhydride and
10 0 mmol svovelsyre.10 0 mmol sulfuric acid.
Varigheten av hvert forsøk er 30 minutter. De spesielle betingelser såvel som de oppnådde resultater vises i tabell The duration of each attempt is 30 minutes. The special conditions as well as the results obtained are shown in a table
I. IN.
I sammenligningsforsøket (a) skjer det dannelse av eddiksyre. I eksemplene 1 til 3 påvises ikke eddiksyre. In the comparative experiment (a), acetic acid is formed. In examples 1 to 3, acetic acid is not detected.
Sammenlianingsforsøk b:Comparison attempt b:
Man gjentar sammenligningsforsøk (a) i det foregående og analyserer de dannede produkter etter henholdsvis 20, 40 og 75 minutters reaksjon. Resultatene er oppført i tabell II (den dannede eddiksyre er ikke bestemt). Comparison test (a) above is repeated and the products formed are analyzed after 20, 40 and 75 minutes of reaction respectively. The results are listed in Table II (the acetic acid formed is not determined).
Disse resultater viser at reaksjonen med dannelse av MVAC er praktisk talt blokkert etter omtrent 20 minutter. These results show that the reaction with formation of MVAC is practically blocked after about 20 minutes.
Eksempel 4:Example 4:
Man gjentar eksempel 2 i det foregående og analyserer de dannede produkter etter henholdsvis 20, 40 og 7 5 minutters reaksjon. Example 2 above is repeated and the products formed are analyzed after 20, 40 and 75 minutes of reaction respectively.
Resultatene er gjengitt i tabell III idet det nevnes at eddiksyre ikke er påvist. The results are reproduced in table III, where it is mentioned that acetic acid has not been detected.
Eksempel 5: Example 5:
Man gjentar eksempel 2 i det foregående ved å doble mengden katalysator idet reaksjonsvarigheten utgjør 20 minutter. Man påviser dannelse av 6,8 mmol MVAC og 3,2 mmol ACH. Example 2 above is repeated by doubling the amount of catalyst, the reaction duration being 20 minutes. Formation of 6.8 mmol MVAC and 3.2 mmol ACH is detected.
Claims (5)
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| FR8808783A FR2633289B1 (en) | 1988-06-24 | 1988-06-24 | PROCESS FOR PRODUCING VINYL ACETATE |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| NO892590D0 NO892590D0 (en) | 1989-06-22 |
| NO892590L true NO892590L (en) | 1989-12-27 |
Family
ID=9367884
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| NO89892590A NO892590L (en) | 1988-06-24 | 1989-06-22 | PROCEDURE FOR THE PREPARATION OF VINYL ACETATE. |
Country Status (7)
| Country | Link |
|---|---|
| EP (1) | EP0348309A1 (en) |
| JP (1) | JPH0267246A (en) |
| KR (1) | KR900000323A (en) |
| BR (1) | BR8903084A (en) |
| FR (1) | FR2633289B1 (en) |
| NO (1) | NO892590L (en) |
| PT (1) | PT90964A (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5719315A (en) * | 1996-12-13 | 1998-02-17 | Eastman Chemical Company | Process for the preparation of vinyl acetate |
| US5731456A (en) * | 1996-12-13 | 1998-03-24 | Eastman Chemical Company | Preparation of vinyl acetate |
| DE10138778A1 (en) | 2001-08-07 | 2003-02-20 | Basf Ag | Joint production of formic acid with a carboxylic (e.g. acetic) acid or derivatives, involves transesterifying a formic ester with a carboxylic acid, followed by carbonylation of the ester obtained |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2860159A (en) * | 1958-11-11 | Decomposition of ethylidene dipropionate | ||
| NL7812485A (en) * | 1977-12-30 | 1979-07-03 | Halcon Res & Dev | PROCESS FOR THE PREPARATION OF VINYL ACETATE. |
| JPS5857417B2 (en) * | 1981-06-22 | 1983-12-20 | 三菱瓦斯化学株式会社 | Manufacturing method of vinyl acetate |
-
1988
- 1988-06-24 FR FR8808783A patent/FR2633289B1/en not_active Expired - Lifetime
-
1989
- 1989-06-08 EP EP89420201A patent/EP0348309A1/en not_active Withdrawn
- 1989-06-22 NO NO89892590A patent/NO892590L/en unknown
- 1989-06-23 JP JP1162460A patent/JPH0267246A/en active Granted
- 1989-06-23 KR KR1019890008729A patent/KR900000323A/en not_active Application Discontinuation
- 1989-06-23 BR BR898903084A patent/BR8903084A/en unknown
- 1989-06-23 PT PT90964A patent/PT90964A/en not_active Application Discontinuation
Also Published As
| Publication number | Publication date |
|---|---|
| FR2633289B1 (en) | 1990-10-05 |
| FR2633289A1 (en) | 1989-12-29 |
| EP0348309A1 (en) | 1989-12-27 |
| BR8903084A (en) | 1990-02-06 |
| JPH0530820B2 (en) | 1993-05-11 |
| NO892590D0 (en) | 1989-06-22 |
| KR900000323A (en) | 1990-01-30 |
| JPH0267246A (en) | 1990-03-07 |
| PT90964A (en) | 1989-12-29 |
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