摘要:
Halides are removed from halide-containing nitrile mixtures by(a) thermally treating the halide-containing nitrile mixture,(b) subsequently adding a base to the thermally treated nitrile mixture and(c) subsequently separating off the base from the nitrile mixture.Amines are prepared by(A) reacting alkyl halides with metal cyanides in an at least two-phase reaction medium in the presence of halide-containing phase-transfer catalysts to give alkanenitriles,(B) separating off the resulting halide-containing alkanenitrile mixture phase and(C) further treating the halide-containing alkanenitrile mixture phase, as described in the stages(a)-(c) removing halides from halide-containing nitrile mixtures and(d) hydrogenating nitrites obtained in stage (c) to give amines, in the presence of suspended or fixed-bed catalysts.
摘要:
In a process for preparing alkylamines by reacting amines and aliphatic aldehydes in the presence of free hydrogen on a fixed bed catalyst in a reactor in which amines and aldehydes are mixed in the catalyst bed after being fed in in separate streams, only the aldehyde stream or only the amine stream is preheated during the feeding in.
摘要:
A process for the preparation of glutaric dialdehyde by the reaction of alkoxy dihydropyrans of the general formula I ##STR1## in which R stands for C.sub.1 to C.sub.20 alkoxy, with water at temperatures ranging from 0.degree. to 150.degree. C. and pressures of from 0.01 to 50 bar in the presence of a which microporous, crystalline aluminum silicate catalyst, e.g. a beta-type zeolite or pentasil catalyst having a pore diameter greater than 5.4 .ANG..
摘要:
In the process for preparing N-ethyldiisopropylamine by reacting acetaldehyde with diisopropylamine and hydrogen at elevated temperature and under pressure in the presence of a hydrogenation catalyst, the catalyst comprises an oxidic support material selected from the group consisting of zirconium dioxide, titanium dioxide, aluminum oxide, silicon dioxide, zinc oxide, magnesium oxide, cerium dioxide, clays and zeolites or mixtures thereof.
摘要:
A process for preparing &bgr;-alkoxynitriles by reacting &agr;,&bgr;-unsaturated nitriles with monohydric, dihydric or trihydric alcohols in the presence of basic catalysts at from −20 to +200° C. comprises using a diazabicycloalkene catalyst of the formula I where from 1 to 4 hydrogen atoms may be independently replaced by the radicals R1 to R4, in which case R1, R2, R3, R4 are each C1-20-alkyl, C6-20-aryl or C7-20-arylalkyl, and n and m are each an integer from 1 to 6.
摘要:
The invention relates to a method for producing the tautomeric form (I) of 2,4,6-trianilino-p-(carbo-2′-ethylhexyl-1′-oxy)-1,3,5-triazine by the crystallization of a tautoner mixture in the presence of one or more solvents selected from the group consisting of aliphatic alcohol having 2 8 C-atoms made of aliphatic alcohol, aliphatic carboxylic acid alkyl esters having a total of between 3–10 C-atoms, aromatic carboxylic acid alkyl esters having a total of between 8–12 C-atoms, aliphatic carboxylic acid esters having a total of between 3 9 C-atoms, carboxylic acid nitriles having a total of between 2–8 C-atoms, dialkylketones having a total of between 3–6 C-atoms and aliphatic sulphones having a total of between 3–6 C-atoms. The solvent or solvent mixture can additionally contain up to 30 wt % of a hydrocarbon (I) acts as a light protecting agent in cosmetic preparations.
摘要:
Process for the preparation of the tautomeric form I of 2,4,6-trianilino-p-(carbo-2′-ethylhexyl-1′-oxy)-1,3,5-triazine by crystallization from a tautomer mixture in the presence of one or more solvents chosen from the group consisting of aliphatic alcohols having 2 to 8 carbon atoms, aliphatic carboxylic alkyl esters having a total of 3 to 10 carbon atoms, aromatic carboxylic alkyl esters having a total of 8 to 12 carbon atoms, aliphatic carbonic esters having a total of 3 to 9 carbon atoms, carbonitriles having a total of 2 to 8 carbon atoms, dialkyl ketones having a total of 3 to 6 carbon atoms and aliphatic sulfones having a total of 3 to 6 carbon atoms, where the solvent or the solvent mixture may additionally comprise up to 30% by weight of a hydrocarbon. I is used as light protection agent in cosmetic preparations.
摘要:
Supported catalysts which are suitable for ammonoxidation, comprising a) a spherical or approximately spherical support material which essentially comprises aluminum oxide, silicon dioxide, titanium dioxide and/or zirconium dioxide and whose bulk density is from 0.6 to 1.2 kg/l, and b) an active material which comprises, as essential components, vanadium and antimony in oxidic form.
摘要:
A process for preparing nitric acid by: catalytically oxidizing ammonia, to obtain a gas mixture containing NO and O2; cooling and condensing the gas mixture, thereby further oxidizing NO with O2, to obtain a gas stream containing NO2/N2O4 and an aqueous solution containing nitric acid; and countercurrently absorbing the NO2/N2O4 from the gas stream in an absorber with process water (H2O), to obtain nitric acid and an NOx-containing absorber offgas, wherein the water content of the nitric acid is regulated to a concentration in the range from 50 to 77.8% by weight and the NOx content of the absorber offgas to a concentration in the range from 20 to 500 ppm, by continuously measuring the water content of the process air supplied to the catalytic gas phase oxidation and, as a function of this, adjusting the amount of process water (Q-H2O) fed to the absorber.
摘要翻译:一种通过以下方式制备硝酸的方法:催化氧化氨,得到含NO和O2的气体混合物; 冷却并冷凝气体混合物,从而进一步用O 2氧化NO,得到含有NO 2 / N 2 O 4的气流和含有硝酸的水溶液; 并用工艺用水(H 2 O)从吸收器中的气流中逆流吸收NO 2 / N 2 O 4,得到硝酸和含NO x的吸收剂废气,其中将硝酸的含水量调节至 50至77.8重量%,并且通过连续测量供应到催化气相氧化的工艺空气的水含量,吸收器的NOx含量废气至浓度在20至500ppm的范围内,并且作为其功能 ,调节供给到吸收器的工艺用水(Q-H 2 O)的量。
摘要:
The invention relates to a method for producing acid chlorides by converting carboxylic acids with carbon oxychlorides or thionyl chloride in the presence of a catalyst adduct of an N,N-disubstituted formamide of general formula (I) and carbon oxychloride or thionyl chloride. In the formula, R1 and R2, independently from one another, mean C1- to C4-alkyl or R1 and R2 together mean a C4- or C5-alkylene chain. According to the inventive method, hydrogen chloride is added during and/or after the conversion.