摘要:
A process for the preparation of butane-1,4-diol by catalytic hydrogenation of a mixture obtained by treating maleic anhydride with an aliphatic alcohol at elevated temperatures, wherein a monohydric or dihydric aliphatic alcohol of boiling point above 180.degree. C. is used and the mixture of maleic acid and the alcohol is obtained by washing a gaseous reaction mixture, which contains maleic anhydride and is obtained in the catalytic oxidation of hydrocarbons by air, with the alcohol.
摘要:
Propylene oxide is prepared by elimination of acetic acid from propylene glycol monoacetates in the presence of a base. In contrast to the conventional elimination of acetic acid in the gas phase, the present reaction is carried out in the liquid phase in a high-boiling solvent. Because of the smaller reaction space required, the reaction in the liquid phase is simpler.
摘要:
In a process for the manufacture of butenediol-dicarboxylic acid esters by reacting butadiene with oxygen and a carboxylic acid in the presence of a noble metal catalyst containing platinum or palladium, the carboxylic acid is added to the reaction mixture in the form of the ester of the acid with a low molecular weight aliphatic alcohol such as methanol and the reaction is carried out under conditions under which the ester undergoes hydrolysis, or the hydrolysis is carried out before the main reaction. This enables the carboxylic acid obtained on further processing of the butenediol esters to be recycled.
摘要:
Carboxylic acid esters of vicinal glycols are prepared by oxidizing olefins with oxygen in the presence of carboxylic acids and of halogen and tellurium salts as catalysts, the reaction being carried out in vessels and apparatus consisting of, or lined with, zirconium or alloys of not less than 80% by weight of zirconium, the remainder being tin and/or hafnium.
摘要:
New and valuable polycyclic compounds which contain nitrogen-containing rings and have a strong action on plants, agents for influencing plant growth containing these compounds, and a method of influencing plant growth with these compounds.
摘要:
Methacrylic acid and butyrolactone are manufactured by hydroformylation of allyl esters of lower carboxylic acids in the presence of rhodium catalysts and inert organic solvents, followed by oxidation of the resulting formyl compounds with molecular oxygen (e.g. with air) in the presence of lower fatty acids, without prior removal of the rhodium catalysts, and elimination of the carboxylic acid from the acyloxybutyric acids formed, at from 150.degree. to 500.degree.C, using catalysts such as aluminum oxide, silicates or active charcoal.
摘要:
By adding water to (meth)acrylonitrile there is formed a concentrated aqueous (meth)acrylamide solution, the addition being effected in the presence of a heterogeneous catalyst at elevated temperature and in aqueous (meth)acrylamide/(meth)acrylonitrile solution at an initial ratio of amide to nitrile of from 1:1 to 1:7.
摘要:
A process for the manufacture of pent-3-enoic acid and its alkyl esters, of the general formulaCH.sub.3 --CH.dbd.CH--CH.sub.2 --CO--ORwhere R is hydrogen or alkyl of 1 to 4 carbon atoms, comprising carbonylating butadiene with carbon monoxide and a compound ROH at from 300 to 1,000 bars CO pressure and from 100.degree. to 160.degree. C. in the presence of cobalt catalysts and nitrogen bases, wherein C.sub.4 cuts are used as starting materials and a tertiary amine having a pK.sub.A of from 3 to 11 is used as the nitrogen base. The pent-3-enoic acid or alkyl esters produced may be used for the manufacture of adipic acid or its alkyl esters, which compounds are starting materials for the manufacture of nylons.
摘要:
Organic isocyanates, preferably alkyl, mono-, di- and/or polyisocyanates or aryl-mono-, di- and/or polyisocyanates, are prepared by thermally cleaving the corresponding urethanes at temperatures of 175.degree. C. to 600.degree. C. in the presence of carbon, preferably in an agitated carbon bed or in a fluidized bed containing carbon.
摘要:
A process for the manufacture of carboxylic acid amides by addition reaction of water with nitriles in the presence of a catalyst which contains copper and magnesium silicate and has been treated with a reducing gas, to which catalyst cement of a certain particle size has been admixed. The amides obtainable by the process are starting materials for the manufacture of solvents, flocculants, wetting agents, pesticides, crop protection agents, textile assistants, e.g. brighteners, water repellent agents, foam stabilizers and detergents.