摘要:
The present invention relates to the field of perfumery. More particularly, it concerns a process for the preparation of 2-methyl-4-phenyl-2-butanol, or even 4-cyclohexyl-2-methyl-2-butanol from 4,4-dimethyl-2,6-diphenyl-1,3-dioxane.
摘要:
This invention relates to the production of terephthalic acid by 1) cycloaddition of 2,5 substituted furan (such as 2,5-bis hydroxymethylfuran or 5-hydroxymethylfurfural) and ethylene, and 2) the subsequent oxidation of the dehydrated cycloaddition product to terephthalic acid. The invention relates more particularly to overall biobased pathways for making terephthalic acid from carbohydrates such as hexoses (e.g., glucose or fructose).
摘要:
The invention relates to a continuous method for the catalytic hydrogenation of an aromatic compound into a cycloaliphatic compound, wherein said method is carried out in a piston reactor provided with a mechanical axially agitating means and comprises continuously feeding a liquid phase comprising said aromatic compound and a catalyst dispersed to the liquid phase, subjecting said liquid phase, at a temperature of between 100° C. and 300° C. and while being mechanical axially agitated, to the effects of a hydrogen pressure of between 10 and 250 bars in the presence of said catalyst dispersed in the liquid phase for a residence time of between 1 second and 10 minutes, and removing the liquid phase from the reactor.
摘要:
The invention relates to a shell catalyst containing ruthenium as an active metal, alone or together with at least one other metal of the auxiliary group IB, VIIB or VIII of the periodical system of the elements (CAS version), and applied to a carrier containing silicon dioxide as a carrier material. The invention also relates to a method for producing said shell catalyst, and to a method for hydrogenating an organic compound containing hydrogenable groups, preferably for hydrogenating a carbocyclic aromatic group to form the corresponding carbocyclic aliphatic groups or for hydrogenating aldehydes to form the corresponding alcohols, using the inventive shell catalyst. The invention further relates to the use of the inventive shell catalyst for hydrogenating an organic compound containing hydrogenable groups, preferably for hydrogenating a carbocyclic aromatic group to form the corresponding carbocyclic aliphatic groups or for hydrogenating aldehydes to form the corresponding alcohols.
摘要:
A process for hydrogenating aromatic compounds in which at least one hydroxyl group is bonded to an aromatic ring comprises bringing at least one of these compounds into contact with free hydrogen in the presence of a catalyst, wherein the catalyst comprises ruthenium and, if desired, at least one metal of transition groups I, VII and VIII in an amount of from 0.01 to 30% by weight, preferably from 0.2 to 15% by weight, based on the total weight of the catalyst, applied to a support, where the support has a mean pore diameter of at least 0.1 .mu.m, preferably at least 0.5 .mu.m, and a surface area of at most 15 m.sup.2 /g, preferably at most 10 m.sup.2 /g.
摘要:
A process for the preparation of cycloalkanols by the hydrolysis of cycloalkyl C.sub.1 -C.sub.4 fatty acid esters, which comprises the following steps:a) reaction of cycloalkyl C.sub.1 -C.sub.4 fatty acid esters with water at a temperature of from 30.degree. to 250.degree. in the liquid phase yielding a reaction mixture consisting of cycloalkyl C.sub.1 -C.sub.4 fatty acid esters, cycloalkanol, C.sub.1 -C.sub.4 fatty acids, and water.b) separation of the reaction mixture obtained in stage a) at a temperature of from 0.degree. to 200.degree. C. into a top phase consisting substantially of cycloalkanol and cycloalkyl C.sub.1 -C.sub.4 fatty acid esters and a bottom phase consisting substantially of water and C.sub.1 -C.sub.4 fatty acids.c) separation of cycloalkanol from the top phase obtained in stage b) by distillation and recycling unconverted cycloalkyl C.sub.1 -C.sub.4 fatty acid esters to stage a).
摘要:
In the hydrogenation of phenol with H.sub.2 over Pd supported catalysts, the ratio of the products formed, cyclohexanone and cyclohexanol, can be predetermined by specific treatment of the catalysts during the initial activation and regeneration by O.sub.2 pretreatment and H.sub.2 treatment, the following time/temperature conditions being used:a) Cyclohexanone:cyclohexanol=85:15 to 98:2a1) for initial activation, no O.sub.2 pretreatment and H.sub.2 treatment for 50-10 hours at 300.degree.-500.degree. C.;a2) for regeneration, O.sub.2 pretreatment for 30-0.5 hours at 220.degree.-380.degree. C. and H.sub.2 treatment for 2-6 hours at 150.degree.-250.degree. C.;b) Cyclohexanone:cyclohexanol=30:70 to below 85:15b1) for initial activation, O.sub.2 pretreatment for 40-3 hours at 250.degree.-500.degree. C. and H.sub.2 treatment for 2-6 hours at 150.degree.-250.degree. C.;b2) for regeneration, O.sub.2 pretreatment for 30-0.5 hours at 380.degree.-600.degree. C. and H.sub.2 treatment for 2-6 hours at 150.degree.-250.degree. C.
摘要:
A process for the preparation of d,l-menthol by catalytic hydrogenation of aromatic or partly hydrogenated cyclic compounds which have the carbon skeleton of menthol having at least one double bond and are substituted by oxygen in the 3-position relative to the methyl group, with simultaneous rearrangement of optically active or inactive stereoisomers of menthol at elevated temperature and under pressure is described. The hydrogenation, which is to be carried out continuously, is carried out on a fixed bed catalyst which comprises, as active constituents, palladium, ruthenium or rhodium or a mixture of these elements, and comprises alkali metal hydroxides and/or alkali metal sulphates as promoters; the support for this catalyst is doped with a rare earth metal and manganese.
摘要:
In an advantageous process for producing powdered aluminium alloys which have a catalytic action or are capable of acting as precursors of catalysts, good results are obtained if the alloy is atomized with water and/or a gas at a temperature of 50.degree. to 500.degree. C. above its melting point and then cooled and dried.
摘要:
Process for the hydrogenation of bis-phenols by reacting bis-phenols with hydrogen in the presence of a catalytic system consisting of palladium supported on activated carbon.