OXIDATIVE-EXTRACTIVE DESULFURIZATION OF DIESEL BY COORDINATED IONIC-LIQUID

Abstract

In the present study, oxidative-extractive desulfurization (OEDS) of actual diesel has been reported using coordinated ionic liquid (IL) and a new-kinetic model has been proposed for OEDS process. A number of ILs prepared by coordination of various solvents [N,N d imethyl-formam ide (DM F). N-methyl-pyrrol idone and dimethyl sulfoxide] with different salts (CaCl2, ZnC12 and MgCl2) were tested for OEDS of diesel. DMF.ZnCl2 which performed the best among these ILs was further used to study the effects of oxidant to sulfur (OIS) molar ratio, diesel to IL volume ratio, temperature and time. Fourier transform infra-red (FTIR) and UV-visible spectroscopy of IL. diesel (before OEDS), ratTinate and extract layer were carried out to understand the removal mechanism. A kinetic model was proposed which assumed extraction of both non-oxidized and oxidized sulfur compounds from diesel. Proposed kinetic model better represented the kinetic data as compared to previously reported models. At the optimized conditions (oxidant to sulfur ratio6:I, diesel to IL volume ratio=3:I and temperature=50 °C). maximum 86% sulfur removal was observed from diesel.