摘要:
Hydroxymethyl-cyclopropane (cyclopropyl-methanol) can be obtained in a manner which is both economical and environment-friendly by catalytic hydrogenation of cyclopropanecarboxylic acid alkyl esters under increased pressure at elevated temperature if a chromium-free zinc oxide catalyst is employed as the catalyst.
摘要:
Ru/Pd catalysts on supports are used for the preparation of mixtures of substituted or unsubstituted cyclohexylamine and substituted or unsubstituted dicyclohexylamine in variable amounts by catalytic hydrogenation of substituted or unsubstituted aniline at elevated temperature and elevated H2 pressure. These catalysts are characterized in that they contain no halogen or sulphur compounds.
摘要:
Catalysts containing ruthenium and palladium for the hydrogenation of aromatic amines to cycloaliphatic amines. Methods for making and using the catalysts.
摘要:
Hydroxymethylcyclopropane is prepared from alkyl cyclopropanecarboxylates by reduction with hydrogen in a process in which use is made of a reduced pelletized catalyst which is obtainable by pressing a mixture of pulverulent copper, zinc and aluminum oxides and subsequent reduction. This process has the advantage that it uses a low-toxicity catalyst which has a long operating life and is particularly suitable for a continuous process and requires relatively low reaction temperatures.
摘要:
Diphenylamine, which can be substituted by lower alkyl and/or lower alkoxy, is obtained from the corresponding N-cyclohexylidene-aniline by catalytic dehydrogenation, a rhodium-containing catalyst being employed.
摘要:
In a process for producing aliphatic .alpha.,.omega.-diols comprising 4 to 12 C atoms from aliphatic .alpha.,.omega.-dicarboxylic acids comprising 4 to 12 C atoms, an oligoester of average chain length n=3 to n=4.5 and with an acid number of 40 to 60 mg KOH/g reaction mixture is first formed from a diol and a dicarboxylic acid, which oligoester is thereafter catalytically hydrogenated in the liquid phase. Hydrogenation is carried out continuously at 180 to 250.degree. C. and at an H.sub.2 pressure of 100 to 400 bar, over a pelletised catalyst which is free from Zn oxide and which comprises pressed powders of Cu, Mn and Al oxides with a content of at least one oxide of metals of subgroup VI of the periodic table of the elements (Mendeleev). The amount of H.sub.2 is 20 to 100 times the amount required stoichiometrically.
摘要:
To prepare a mixture of cyclohexylamine and dicyclohexylamine by catalytic hydrogenation of aniline at elevated temperature and elevated H.sub.2 pressure, the catalyst system used comprises two reduced, unsupported catalysts A and B which are prepared from pressed element (hydr)oxide powders. Catalyst A comprises one or more of Fe, Co, Ni, also Mn, Cu and one or more of Ca, Sr, Ba. Catalyst B comprises one or more of Fe, Co, Ni, also Mn, Si and Mg.
摘要:
The preparation of optionally substituted diphenylamine by reaction of optionally substituted aniline with optionally substituted cyclohexanone using a supported Rh catalyst containing rhodium or a combination of rhodium with another platinum metal from the group of palladium, platinum, ruthenium or iridium and which can additionally contain chromium, manganese, alkali metal and a sulphur compound is described. The catalyst of the invention is prepared from halide-free starting materials. The Rh catalyst is distinguished by a low dependence of the initial selectivity, the selectivity in the run-in state and the running-in time on the conditions of the reductive pretreatment and requires only short running-in times to the optimum state.
摘要:
Cyclohexylamine and dicyclohexylamine can be prepared as a mixture with one another by reaction of phenol with aniline, ammonia or a mixture of aniline and ammonia in the presence of hydrogen over a catalyst, the reaction being carried out according to the invention over a palladium catalyst which has a support of niobic acid or tantalic acid or a mixture of niobic acid and tantalic acid or a support containing such acids. The reaction is carried out at 100.degree.-220.degree. C. under an H.sub.2 partial pressure of 0.5-500 bar.
摘要:
Optionally substituted diphenylamines can be obtained by reacting optionally substituted anilines with optionally substituted cyclohexanones over a supported catalyst at 200.degree.-450.degree. C. and 0.1-20 bar, the supported catalyst containing one or more metals having a dehydrogenating action selected from the group Ru, Pd, Os, Ir, Pt, Fe, Co, Ni, Re, Mn, Cu, Ag, Cr and Ce.