摘要:
A process for preparing tertiary alkyl esters of (meth)acrylic acid having at least 4 carbon atoms in the alkyl radical, comprising the steps of: (1) reacting (meth)acrylic acid with at least one olefin of the general formula I: in which R1 and R2 are an alkyl radical, and R3 is a hydrogen atom, an alkyl radical, a cycloalkyl radical, an aryl radical, an alkylcycloalkyl radical, an alkylaryl radical, a cycloalkylaryl radical, or an alkylcycloalkylaryl radical; in homogeneous phase in the presence of an acidic catalyst in a reactor, (2) discharging the resulting reaction mixture (1) from the reactor, (3) separating the discharged reaction mixture (2) into a mixture (3.1) which comprises the catalyst and a mixture (3.2) which comprises the tertiary alkyl ester of (meth)acrylic acid having at least 4 carbon atoms in the alkyl radical, and (4) removing the tertiary alkyl ester of (meth)acrylic acid having at least 4 carbon atoms in the alkyl radical from the mixture (3.2), wherein, (5) in process step (4), at least one compound S which comprises at least one N-oxyl group is added as a stabilizer.
摘要:
Process for polymerizing at least one olefinic monomer in a loop reactor at from 20 to 150° C., but below the melting point of the polymer to be formed, and a pressure of from 5 to 100 bar, where the polymer formed is present in a suspension in a liquid or supercritical suspension medium and this suspension is circulated by means of an axial pump, wherein the loop reactor comprises a cyclic reactor tube whose diameter varies by at least 10%, based on the predominant reactor tube diameter, and in which there is at least one widening and narrowing in a region other than that of the axial pump.
摘要:
Amines are prepared from primary or secondary alcohols and nitrogen compounds selected from the group of ammonia, primary and secondary amines, at from 80 to 250.degree. C. under pressures from 0.1 to 40 MPa with hydrogen in the presence of a catalyst comprising zirconium, copper and nickel, wherein the catalytically active composition comprises20-85% by weight of oxygen-containing zirconium compounds, calculated as ZrO.sub.2,1-30% by weight of oxygen-containing copper compounds, calculated as CuO,14-70% by weight of oxygen-containing nickel compounds, calculated as NiO, where the molar ratio of nickel to copper is greater than 1,0-10% by weight of oxygen-containing aluminum and/or manganese compounds, calculated as Al.sub.2 O.sub.3 and/or MnO.sub.2,and no oxygen-containing cobalt or molybdenum compounds.
摘要翻译:在含有锆,铜和铜的催化剂存在下,在氢气压力为0.1至40MPa的压力下,从伯,仲醇和选自氨,伯胺和仲胺的氮化合物制备胺。 和镍,其中催化活性组合物包含20-85重量%的以ZrO 2计算的含氧锆化合物,1-30重量%的以CuO计的含氧铜化合物,14-70重量% 以NiO计算的含氧镍化合物,其中镍与铜的摩尔比大于1-10重量%,以Al 2 O 3和/或MnO 2计算的含氧铝和/或锰化合物为0-10重量% 含氧钴或钼化合物。
摘要:
A process for preparing N-alkyl-substituted aminoalkynes by reacting an alkyne with a carbonyl compound and an amine with heterogeneous catalysis in which an unsupported copper acetylide derived from malachite is used as the catalyst. The N-alkyl-substituted aminoalkyne have a wide variety of uses including their use as precursors for pharmaceuticals, their use in electroplating processes and their use as corrosion inhibitors.
摘要:
A hydrogenation catalyst based on an alloy of aluminum and of a transition metal is prepared by preparing a kneaded material from the alloy and an assistant, converting the kneaded material into moldings, calcining the moldings and treating the calcined moldings with an alkali metal hydroxide, by a process in which the assistant used is (a) polyvinyl alcohol and water or (b) stearic acid, and the catalyst prepared according to the invention is used for hydrogenation and hydrogenolysis, in particular the partial hydrogenation of aliphatic alpha,omega-dinitriles to aliphatic alpha,omega-aminonitriles.
摘要:
A catalyst solid comprising: A) support particles having a mean particle diameter d50 of from 5 to 200 μm and a specific surface area of from 30 to 1 000 m2/g and obtainable by agglomeration of primary particles of a pyrogenic silica having a mean particle diameter dm of from 1 to 50 nm, and B) at least one organic transition metal compound, can be used for the polymerization or copolymerization of olefins.
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:
The invention relates to a process for preparing a supported catalyst, in particular for the polymerization and/or copolymerization of olefins, which comprises: a) preparing a hydrogel; b) milling the hydrogel to give a finely particulate hydrogel; c) producing a slurry based on the finely particulate hydrogel; d) drying the slurry comprising the finely particulate hydrogel to give the support for catalysts; e) producing the supported catalyst by applying at least one transition metal and/or at least one transition metal compound to the support for catalysts and, if appropriate, activating the applied metal and/or compound, wherein a finely particulate hydrogel in which at least 5% by volume of the particles, based on the total volume of the particles, have a particle size in the range from >0 μm to ≦3 μm; and/or at least 40% by volume of the particles, based on the total volume of the particles, have a particle size in the range from >0 μm to ≦12 μm, and/or at least 75% by volume of the particles, based on the total volume of the particles, have a particle size in the range from >0 μm to ≦35 μm, is produced in step b) and a support which can be prepared as set forth in steps a) to d) is used to produce catalysts in step e).
摘要:
Novel supported, titanized chromium catalysts for the homopolymerization of ethylene and the copolymerization of ethylene with α-olefins, a process for preparing them and to their use for the polymerization of olefins.
摘要:
In a process for preparing alcohols by gas phase hydrogenation of carboxylic acids or esters thereof at elevated temperature and elevated pressure in the presence of catalysts consisting of or comprising, as hydrogenating components, oxides of main group VI and/or subgroup IV, the hydrogenation is carried outa) at from 250.degree. C. to 400.degree. C. and from 5 bar to 100 bar in the presence ofb) primary or secondary alcohols, the molar hydrogen/alcohol ratio being at most 800.