Desulphurization of Crude Oil Using Solid Support Ionic Liquid

Nowadays, the rapid development in each country in the world shows high demand for petroleum based product as an energy especially for fuel, thus specifications of fuels (particularly gasoline and diesel) became and are getting more and more stringent and Sulfur specifications getting lower and down to 50ppm. Conventional method for sulphur removal in refining process is the catalytic hydrodesulfurization (HDS technology) operating at high temperature and pressure. HDS is a very costly process that required high hydrogen consumption under severe condition and it is inefficient to reduce aromatic sulphur compounds.
Hence, green solvent known as ionic liquid was introduced as alternative to remove sulphur from hydrocarbon mixtures. Ionic liquids nominated as ideal candidates for this issue since most of the species are low melting salts (<100 °C) with no measurable vapour pressure, and represent a relatively new class of solvents and extracting agents. Ionic liquids also have excellent extraction properties for organic S- and N-compounds and if chosen wisely, insoluble in oil.
By using technique of solid-liquid extraction, 1-Butyl-3-methylimidazolium tetrachloroferrate [BMIM](FeCl4) solid support ionic liquid was synthesized and tested for its capability to extract organic sulphur species from real, refinery obtained hydrocarbon fuels, natural raw crude oil and model oil in mild temperature (25°C) and offshore operation condition (80°C). The hydrocarbons consisted of various types of sulphur species as well as pre-treated, partially desulphurized hydrocarbon mixtures. The sulphur extracted from hydrocarbons mixtures were then analysed for total sulphur analyser. Total sulphur was significantly lowered in all tested hydrocarbon mixtures. Way forward to further study on reuse and regeneration of the solid support ionic liquid candidate were suggested after all results and analysis take place.