Glycerine recovery from spent soap lye 2 chemical

Thesis Abstract

The recovery of glycerine from spent soap lye has been done using soap lye samples obtained from the hot process of soap production using palm kernel oil (P.K.O). The main advantage of hot process is that exact concentration of the lye solution is not known, but to perform this with adequate success, the lye and fat are boiled together at 80 – 1000C at times above 1000C until saponification occurs. The overall weight of glycerine recovered per 100g of oil used was 9.0g. The quantity of spent soap lye obtained was 250ml, Acid value was 555.39, percentage free acid value was 5.6%, total fatty acid = 7.131, percentage free caustic acid = 0.14%, percentage free fatty acid obtained was 0.07131%, the specific gravity was 1.059, purity of glycerine was 92%. These parameters obtained were measured relatively to international standards with negligible error due to the type of equipment used. From the result, it is evident that the amount of glycerine recovered depends largely on the quantity of spent soap lye. Other processes the spend soap lye and the glycerine undergo as may be seen in other chapters includes, salting out, filtration, splitting and others.