Kinetics of organic sulphur removal from coal by oxydesulphurization

Abstract

This paper presents some experimental data for the kinetics of organic sulphur removal from Lower Freeport coal by oxidation in an aqueous medium. The experimental data were obtained in a semi-batch (gas flow, no flow of slurry) agitated reactor for the ranges of temperature 403-473 K, oxygen partial pressure 0.32-1.36 MPa, solids loading 3-26 wt%, average coal particle size 75-955 μm and time 0-5400 s. The experimental data were taken under acidic, neutral and alkaline conditions. The results indicate that under acidic conditions, no organic sulphur was removed at moderate and low pressures and temperatures. Whenever significant organic sulphur was removed, the removal rate followed first-order kinetics with respect to the organic sulphur. Under otherwise identical conditions, the organic sulphur removal increased with the pH of the aqueous medium.