Optimization of synthetic conditions of explosive emulsifier Span 80

Abstract

Abstract In this paper, the effects of the two-step synthesis process on the acid value, saponification value and hydroxyl value of the samples, such as the molar ratio of Span 80 sorbitol to industrial oleic acid, the amount of catalyst used in etherification and esterification stages, reaction temperature and reaction time were studied. The results showed that 200g of sorbitol and 500g of industrial oleic acid had a vacuum degree of 0.085 MPa in the etherification stage, phosphoric acid with a mass concentration of 0.5% was used as catalyst in etherification stage, and the reaction time was 2 h with a gradient temperature rise of 150 °C; for esterification stage, NaOH solution with a mass concentration of 0.6% was used as catalyst, and the gradient temperature rise formula was 220 °C, and the reaction time was 2.5 h with a final quench method to obtain high-quality Span 80 had an acid value of 1.781 mgKOH/g, a hydroxyl value of 201.136 mgKOH/g and a saponification value of 152.614 mgKOH/g, which conforms to the national standard of high quality Span 80.