Abstract: A process is disclosed for preparing D,L-aspartic acid by beating aqueous solutions of ammonium salts of the maleic acid. The molar ratio of maleic acid to ammonia ranges from 1:1 to 1:50. The process is carried out at temperatures from 60.degree. to 250.degree. C. and pressures of at least 1 bar. The pressure applied during the reaction is adjusted to ensure that the reaction mixture is almost completely present in liquid phase. Excess ammonia is removed and the reaction solution is acidified so as to release D,L-aspartic acid, which is then isolated.

Abstract: Aliphatic alpha,omega-aminonitriles are prepared by partial hydrogenation of aliphatic alpha,omega-dinitriles at elevated temperatures in the presence of a catalyst in the gas phase by a process which comprises carrying out the hydrogenation with a catalyst based on at least one metal selected from the group consisting of nickel, cobalt, ruthenium and rhodium and with the proviso that the catalyst is not a powder.