Desulphurization of a fluid coke similar to the Athabasca oil sands coke

Almost complete desulphurization of a high-sulphur fluid coke was achieved by impregnating the coke with suitable alkaline reagents followed by high-temperature calcination in an inert atmosphere and subsequent leaching of the coke to remove soluble metal sulphides formed during calcination. Sodium hydroxide and sodium carbonate were found to be the most effective bases. Sodium sulphide was detected in the calcined, non-leached coke by X-ray diffraction. Methane, carbon monoxide, carbon dioxide, ammonia and water, in addition to hydrogen sulphide, were detected in the gaseous product stream by gas chromatography. Flow rate of the inert gas and the particle size of the coke employed in this investigation had no effect on the extent of desulphurization. A maximum desulphurization was observed at a calcination temperature of 850 °C.