Abstract: A process for the production of a water-soluble carbodiimide, which comprises(1) allowing ethyl isothiocyanate to react with N,N-dimethyl-1,3-propanediamine in an aromatic hydrocarbon solvent (first reaction step),(2) removing hydrogen sulfide from a thiourea derivative formed in the first reaction step upon adding a hydrogen sulfide removing agent without isolating the thiourea derivative (second reaction step), and(3) recovering a water-soluble carbodiimide from the resulting reaction mixture.

Abstract: Disclosed is a process for preparing DL-serine, which comprises synthesizing DL-serine according to Strecker reaction with use of a cyan compound, ammonium chloride, ammonia and a reaction substrate comprising glycol aldehyde, wherein the Strecker reaction is carried out under the reaction conditions of:molar ratios of the starting materials of:glycol aldehyde/cyan compound: more than 1.0 and not more than 1.50ammonium chloride/glycol aldehyde: more than 1.0 and not more than 2.0ammonium/cyan compound: 1.0 to 7.0reaction temperature: 20.degree. to 80.degree. C.reaction time: 15 to 120 minutes,and the reaction product obained in hydrolyzed.

Abstract: There is disclosed a process for preparing glycol aldehyde from ethylene glycol by use of a complex system catalyst comprising copper and other inorganic component, which comprises permitting 0.001 to 0.3 mole of oxygen per one mole of ethylene glycol to be copresent in the reaction system.