Study of rheological properties of pre-saponated cotton soapstock obtained by the nuclear method

Abstract

Soapstock is a valuable secondary resource for the oil and fat industry, from which various surfactants, fatty acids, detergents, etc, can be obtained. This article presents comparative results of a study on processing cotton soapstock by the alkaline hydrolysis method of saponification with subsequent salting of the soap mass with table salt. For this purpose, the original soapstock (SP) was diluted with water from 1:1 to 1:4 times relative to the original mass. It was experimentally shown that the density and viscosity of the soap core emulsion, compared to raw soap stock, exceed from 1.11 to 1.74, from 1.01 to 1.07, and 1.66 to 6 times. At the same time, compared to raw diluted soapstock, these values exceed from 0.94 to 1.48 and from 1.67 to 5 times, respectively. This suggests that after salting, the salt solution several times exceeds the density and viscosity of the direct emulsion “oil-fat in water”.

From the point of view of material and raw material resources, as well as technological indicators, the most optimal condition for obtaining a transportable soap emulsion is the “Sample pickling” with a mass ratio of SP: H₂O = 2. The results of the degree of settling of the soap core showed the possibility of increasing the settling rate by a sufficient 2 hours. Rheological characteristics of presaponified and salted cotton soapstock indicate the acceptability of pumping the soap core emulsion from one apparatus to another and holding it for sufficient storage periods.