SUPERCRITICAL FLUID EXTRACTION OF TURKISH LIGNITES AND OIL SHALE WITH TOLUENE MIXTURES

Abstract
Supercritical -Fluid extraction (SFE) of two Turkish lignites and oil shale with toluene mixtures were investigated. Experiments were performed in a batch autoclave at 623 K. Extracts recovered from SFE were fractionated into oils, asphaltenes and preasphal-tenes by solvent extraction. The conversion of lignites decreased with increasing n-pentane content in the mixture. The extraction yield and the products (oils, AS, PAS) increased with increasing n-pentane content in its range below 15 % The conversion and the extract yield obtained from Cöynük ail shale is higher with toluene mixture than toluene.