Utilization of waste cooking oil as raw material for synthesis of Methyl Ester Sulfonates (MES) surfactant

Abstract

In this study, MES surfactant was synthesized from waste cooking oil (WCO) which can lower the synthesis cost and represent efficient utilization of waste.MESis an eco-friendly anionic surfactant, which can be used for our detergent application. The purpose of this study was to obtain optimum MES surfactant from purification of WCO. WCO is purified first to reduce high impurities and free fatty acid (FFA). Purification steps of WCO consist of filtration to separate food residues, neutralization with various concentrations of NaOH solution13%;14%;15%;16% and bleaching with activated carbon 7.5% (wt. % of oil). After purification followed by trans-esterification process with variation of mole ratio oil and methanol 1:8; 1:9; 1:10 then synthesized MES surfactant with sodium bisulfite (NaHSO3) as sulfonating agent. Neutralization results showed high reduction percentage of FFA was 31.31% for 15% NaOH solution; bleaching results showed reduction percentage of FFA was 20.27% and WCO color was originally dark brown to be light yellow. The results of trans-esterification showed highest yields 94.15% for mole ratio of oil and methanol 1:9 and sulfonation results will be described further in this paper.