Desulfurization and Demineralization of Asphaltite Using Combination of Froth Flotation and Aqueous Caustic Leaching

Abstract

The mineral matter and sulfur, which are present in varying amounts in asphaltites, are a major problem in utilization of asphaltites as a fuel. The effect of leaching asphaltites from Sirnak and Silopi, SE Anatolia, Turkey, with froth flotation following aqueous sodium hydroxide on desulfurization and deashing was investigated. Froth flotation reduced the ash content of asphaltite by 35.8 % and 35.3 %, pyritic sulfur 22.55 % and 8.7 % (wt %) and its volatile matter content by 28.9 % and 28.9 %. The asphaltite flotation yield was 79.1 % and 85.3 %. Never organic sulfur could be removed by froth flotation. The asphaltite concentration obtained from flotation was leached using aqueous sodium hydroxide and its organic sulfur content was reduced by 60.8% and 61.9 %. Hence using combination of the two methods, the total sulfur, ash and volatile matter contents was reduced by 76.4% and 71.4 %, 38.1 % and 38.3 %, 44.1 % and 47.2 %, respectively.