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:
A process for preparing an NH.sub.2 -containing compound by hydrogenating a compound containing at least one unsaturated carbon-nitrogen bond with hydrogen in the presence of a catalyst at temperatures not below room temperature and elevated hydrogen partial pressure in the presence or absence of a solvent which process includes the following steps: a) using a catalyst comprising a cobalt- and/or iron-containing catalyst, and b) after the conversion based on the compound to be hydrogenated and/or the selectivity based on the desired product has or have dropped below a defined value or the amount of an unwanted by-product has risen beyond a defined value, interrupting the hydrogenation by stopping the feed of the compound to be hydrogenated and of the solvent, if used, c) 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 d) subsequently continuing the hydrogenation of the compound containing at least one unsaturated carbon-nitrogen bond.
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:
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).
摘要:
A catalyst suitable for preparing aliphatic alpha, omega-aminonitriles by partial hydrogenation of aliphatic dinitriles comprises(a) metallic cobalt, a cobalt compound or a mixture thereof, the proportion of metallic cobalt based on (a) being from 20 to 100% by weight,(b) from 10 to 70% by weight, based on (a), of metallic iron, iron oxide, a further iron compound or a mixture thereof, the proportion of iron oxide based on (b) being from 20 to 100% by weight,(c) from 0 to 1% by weight, based on (a), of a compound based on an alkali metal, an alkaline earth metal or zinc.
摘要:
A process for hydrogenation of aliphatic alpha, omega-dinitriles in the presence of a heterogeneous fixed bed catalyst comprises using a reaction mixture comprising from 2 &mgr;mol to 30 mmol NA, K, Rb, Cs, Mg, Ca, Sr, Ba or Mn or mixtures thereof in the form of a basic salt, based on 10 mol of aliphatic alpha, omega-dinitrile used.
摘要:
A process for preparing aliphatic alpha,omega-amino nitrites by partial hydrogenation of aliphatic alpha,omega-dinitriles in the presence of a catalyst, wherein the catalyst used for the partial hydrogenation comprises (a) iron or a compound based on iron or mixtures thereof and (b) from 0.01 to 5% 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 (c) from 0 to 5% by weight, based on (a), of a compound based on an alkali metal or alkaline earth metal.
摘要:
A process for coproduction of 6-aminocapronitrile and hexamethylenediamine starting from a mixture comprising a phosphorus-containing compound and essentially adiponitrile and obtained by reaction of butadiene with hydrocyanic acid in the presence of a catalyst comprising a phosphorus-containing compound comprises(1) reducing the weight proportion of phosphorus-containing compound, calculated as phosphorus, in the mixture,(2) partially hydrogenating the resulting mixture in the presence of a catalyst to form an .alpha.,.omega.-aminonitrile, and(3) removing 6-aminocapronitrile and hexamethylenediamine from the mixture.