摘要:
A process for the continuous preparation of homopolymers of ethyleneimine by polymerization of ethyleneimine in a solvent in the presence of catalysts at temperatures of at least 80.degree. C., in homogeneous liquid phase in a tubular reactor in which the ratio of length to internal diameter is at least 5:1. There are obtained polyethyleneimines having a content of secondary nitrogen atoms of more than 40 to 60% and molecular weight distribution M.sub.w /M.sub.n of from 1.5:1 to 3:1.
摘要:
The invention relates to a process for recovering 3-aminomethyl-3,5,5-trimethylcyclohexylamine(isophoronediamine, IPDA) having a cis/trans isomer ratio of at least 73/27 by fractional distillation, which comprises the following steps: a) providing IPDA in a cis/trans isomer ratio of
摘要:
The invention relates to processes for preparing 3-aminomethyl-3,5,5-trimethylcyclo-hexylamine (isophoronediamine, IPDA) having a high cis/trans isomer ratio. IPDA having a cis/trans isomer ratio in the range from 63/37 to 66/34 can be obtained in any desired cis/trans isomer ratio, irrespective of temperature, by reacting IPDA with H2 and NH3 in the presence of a hydrogenation catalyst. IPDA having a cis/trans isomer ratio of at least 73/27 which is an important starting material for the synthesis of polyurethanes and polyamides can be obtained by combining this isomerization process with distillative processes.
摘要:
A process for preparing dialkylamides of the alkali metals by reacting the corresponding dialkylamine with the corresponding alkali metal in the presence of an electron-donating substance selected from the group consisting of 1,3-butadiene, isoprene, naphthalene and styrene with formation of small amounts of butenyldialkylamine comprises suspending the corresponding alkali metal in a solvent and subsequently adding dialkylamine and electron-donating substance in such a way that the dialkylamine is present in an amount of up to 45% by weight, preferably up to 25% by, weight, in particular up to 15% by weight, and the butadiene is present in an amount of up to 5% by weight, preferably up to 3% by weight, in particular up to 1.5% by weight.
摘要:
A process for regenerating a zeolite catalyst comprises the following stages: (I) Heating a partially or completely deactivated catalyst to 250-600° C. in an atmosphere which contains less than 2% by volume of oxygen, (II) treating the catalyst at from 250 to 800° C., preferably from 350 to 600° C., with a gas stream which contains from 0.1 to 4% by volume of an oxygen-donating substance or of oxygen or of a mixture of two or more thereof, and (III) treating the catalyst at from 250 to 800° C., preferably from 350 to 600° C., with a gas stream which contains from more than 4 to 100% by volume of an oxygen-donating substance or of oxygen or of a mixture of two or more thereof.
摘要:
A catalyst comprises, based on the total weight of the catalyst,0.1-6% by weight of cobalt, nickel or a mixture thereof,0.001-25% by weight of ruthenium,0-10% by weight of copper and0-5% by weight of promoterson a porous metal oxide carrier.It preferably comprises 0.1-3% by weight of cobalt and 0.1-3% by weight of nickel. It can be used in hydrogenation reactions, dehydrogenation reactions or hydrogenation/dehydrogenation reactions, in particular in the amination of alkylene oxides, alcohols, aldehydes or ketones with ammonia or primary or secondary amines.
摘要:
In an oxidation catalyst based on a titanium or vanadium silicalite having a zeolite structure and containing from 0.01 to 20% by weight of one or more platinum metals selected from the group consisting of ruthenium, rhodium, palladium, osmium, iridium and platinum, the platinum metals are each present in at least two different bond energy states and preferably have no metal-metal bonds.
摘要:
A process for the preparation of 3-aminomethyl-3,5,5-trimethylcyclohexylamine from 3-cyano-3,5,5-trimethylcyclohexanone which requires three spatially separated reaction spaces, in order to carry out the following three steps in sequence: a) reacting the 3-cyano-3,5,5-trimethylcyclohexanone with excess ammonia on acidic metal-oxide catalysts in a first reaction space at from 20.degree. to 150.degree. C. and from 50 to 300 bar, b) hydrogenating the resultant reaction products using hydrogen in a second reaction space in the presence of excess ammonia and preferably liquid ammonia on hydrogenation catalysts, optionally using basic components or on neutral or basic supports at from 50.degree. to 100.degree. C. and at from 50 to 300 bar, and c) hydrogenating the resultant reaction products in the presence of hydrogen and also ammonia in a third reaction space on hydrogenation catalysts, optionally using basic components or on neutral or basic supports at from 110.degree. to 160.degree. C. and at from 150 to 300 bar.These three steps in sequence provide a substantially complete reaction of the original 3-cyano-3,3,5-trimethylcyclohexanone reactant with a yield of 96% of the desired diamino product in which the cis-content of the diamine is 70%.
摘要:
6-Aminocaproic esters are prepared by reacting alkyl 5-formylvalerates with excess ammonia and hydrogen in the presence of ruthenium catalysts at elevated temperature under superatmospheric pressure in liquid ammonia as reaction medium.
摘要:
Alkyl pentenoates are prepared by(a) reacting butadiene or a butadiene-containing hydrocarbon mixture with carbon monoxide and an alkanol in the presence of a tertiary aromatic heterocyclic nitrogen base and a cobalt carbonyl catalyst at from 80.degree. to 160.degree. C. under from 100 to 1,000 bar to obtain a reaction mixture which contains alkyl pentenoate, C.sub.6 -diester, tertiary nitrogen base, alkanol, butadiene, hydrocarbon and by-product,(b) substantially removing from the reaction mixture obtained any excess hydrocarbon, nitrogen base, alkanol and alkyl pentenoate by distillation to obtain a residue which contains cobalt carbonyl catalyst,(c) bringing the residue which contains cobalt carbonyl catalyst into contact with a mixture of carbon monoxide and hydrogen at elevated temperature and elevated pressure, and(d) recycling the residue which contains cobalt carbonyl catalyst into alkyl pentenoate synthesis stage (a).