The synthesis procedure of an amphoteric surfactant CAB-H has been optimized according to the literature and specific situation of the workshop in our company. This procedure consists of two steps. Firstly, hydrogenated cocoamidopropyl dimethylamine (PKO-H) was synthesized by hydrogenated lauric acid and N, N-dimethylaminopropyl-amine. The optimum reaction conditions involved the mole ration of N,N-dimethylamino-propylamine and hydrogenated coco acid was 1.10:1(mol/mol), and the reaction was heated at 160-1...