摘要:
In a process for preparing phthalic anhydride by passing a gas stream comprising o-xylene, oxygen and sulfur dioxide at elevated temperature over a catalyst comprising heavy metals, the content of N-acyl compounds in the gas stream is restricted to less than 200 ppm, based on the weight of o-xylene.
摘要:
A process for preparing phthalic anhydride by gas-phase oxidation of xylene, naphthalene or mixtures thereof over two different fixed-bed catalysts arranged in zones in a shell-and-tube reactor which is thermostated by means of a heat transfer medium is carried out so that the maximum temperature in the second catalyst zone in the flow direction is at least 52° C. lower than the maximum temperature in the first catalyst zone. The process of the present invention makes it possible to prepare phthalic anhydride in high yields under conditions relevant to industrial practice.
摘要:
A process for preparing aliphatic alpha, omega-diamines by hydrogenation of aliphatic alpha, omega-dinitriles in the presence of a catalyst comprises using a hydrogenation catalyst comprising (a) iron or a compound based on iron or mixtures thereof, (b) from 0.001 to 0.3% by weight based on (a) of a promoter based on 2, 3, 4 or 5 elements selected from the group consisting of aluminum, silicon, zirconium, titanium and vanadium, and also (c) from 0 to 0.3% by weight based on (a) of a compound based on an alkali and/or alkaline earth metal.
摘要:
A process for recovering hexamethylenediamine (I) from a mixture (II) including(I) hexamethylenediamine,(III) hexamethyleneimine,(IV) a compound selected from 2-aminomethylcyclopentylamine and 1,2-diaminocyclohexane,(V) an imine,(VI) adiponitrile and 6-aminocapronitrileincludes distilling(a) a mixture (II) to obtain(a1) a low boiling fraction (III),(a2) a medium boiling fraction (VII) (I), (IV) and (V), and(a3) a high boiling fraction (V) and (VI),(b) a mixture (VII) to obtain(b1) an overhead product (IV), and(b2) a mixture (VIII) (I) and (V) as bottom product, and(c) a mixture (VIII) to obtain(c1) (I) as overhead product, and(c2) a bottom product (V).
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 the coproduction of 6-aminocapronitrile (ACN) and hexamethylenediamine (HMD) by treatment of adiponitrile (ADN) with hydrogen in the presence of a nickel-containing catalyst at temperatures not below room temperature and elevated hydrogen partial pressure in the presence or absence of a solvent comprises, after the conversion based on ADN and/or the selectivity based on ACN has or have dropped below a defined value(a) interrupting the treatment of ADN with hydrogen by stopping the feed of ADN and of the solvent, if used,(b) treating the catalyst at from 150.degree. to 400.degree. C. with hydrogen using a hydrogen pressure within the range from 0.1 to 30 MPa and a treatment time within the range from 2 to 48 h, and(c) then continuing the hydrogenation of ADN with the treated catalyst of stage (b).
摘要:
Novel 2-cyanoacrylic esters I ##STR1## where the radicals have the following meanings: R.sup.1 and R.sup.2 are each hydrogen or a radical having an iso- or heterocyclic ring system with at least one iso- or heteroaromatic nucleus, and at least one of the radicals R.sup.1 or R.sup.2 must be different from hydrogen, n is from 2 to 10, and X is, when n=2, a radical of the formula II ##STR2## where m is from 2 to 8, and X is, when n>2, the radical of an n-hydric aliphatic or cycloaliphatic polyol having 3-20 carbon atoms, it also being possible for a cycloaliphatic radical to contain 1 or 2 hetero atoms, and for an aliphatic radical to be interrupted by up to 8 non-adjacent oxygen atoms, sulfur atoms, imino or C.sub.1 -C.sub.4 -alkylimino groups, are used as light stabilizers.
摘要:
3-Aminomethyl-3,5,5-trimethylcyclohexylamine is prepared by reacting 3-cyano-3,5,5-trimethylcyclohexanone with 3-aminomethyl-3,5,5-trimethylcyclohexylamine and subsequently or simultaneously adding ammonia under a hydrogen pressure of from 50 to 300 bar in the presence of a hydrogenation catalyst at from 20.degree. to 150.degree. C., by a process in which the reaction is carried out without removing the water of reaction.
摘要:
A process for catalytic hydrogenation of adiponitrile to hexamethylenediamine at elevated temperature and elevated pressure in the presence of catalysts based on elemental iron as catalytically active component and ammonia as solvent comprises a) hydrogenating adiponitrile at from 70 to 220° C. and from 100 to 400 bar in the presence of catalysts based on elemental iron as catalytically active component and ammonia as solvent to obtain a mixture comprising adiponitrile, 6-aminocapronitrile, hexamethylenediamine and high boilers until the sum total of the 6-aminocapronitrile concentration and the adiponitrile concentration is within the range from 1 to 50% by weight, based on the ammonia-free hydrogenation mixture, b) removing ammonia from the hydrogenation effluent, c) removing hexamethylenediamine from the remaining mixture, d) separating 6-aminocapronitrile and adiponitrile from high boilers individually or together, and e) returning 6-aminocapronitrile, adiponitrile or mixtures thereof into step a).
摘要:
A process for the coproduction of 6-aminocapronitrile (ACN) and hexamethylenediamine (HMD) by treatment of adiponitrile (ADN) with hydrogen in the presence of a nickel-containing catalyst at temperatures not below room temperature and elevated hydrogen partial pressure in the presence or absence of a solvent comprises, after the conversion based on ADN and/or the selectivity based on ACN has or have dropped below a defined value(a) interrupting the treatment of ADN with hydrogen by stopping the feed of ADN and of the solvent, if used,(b) treating the catalyst at from 150 to 400.degree. C. with hydrogen using a hydrogen pressure within the range from 0.1 to 30 MPa and a treatment time within the range from 2 to 48 h, and(c) then continuing the hydrogenation of ADN with the treated catalyst of stage (b).