Preparation of sulfated/sulfonated castor oil based on SO3 membrane sulfonation process and its properties
Based on the concept of environmentally friendly production,five kinds of sulfated castor oil with different organically combined sulfuric anhydride were successfully prepared by sulfur trioxide mem-brane sulfonation process instead of the traditional concentrated sulfuric acid process,which solved the problem of waste acid and waste inorganic salts in the traditional preparation process.The successful prep-aration of sulfated castor oil was demonstrated by means of infrared spectroscopy and chemical analysis.The properties of five sulfated castor oils with different organically combined sulfuric anhydride,namely surface tension,dynamic surface tension,emulsifying power,particle size and leather fatliquoring applica-tion,were studied and compared with commercially available products.The results showed that compared with the commercially available products,the sulfated castor oil prepared by SO3 process had better sur-face activity,with a minimum γcmc of 43.0 mN/m,a cmc of 9.3 mg/L,good emulsifying power,a particle size of less than 200 nm,and excellent fatliqouring performance.