Characterization of products from two lignite samples by supercritical fluid extraction

Supercritical fluid extractions (SFEs) of Ilgin and Tuncbilek lignites from Turkish resources using toluene as solvent were investigated. Experiments were performed in a batch autoclave at 633 K. The yields of extracts from supercritical toluene extractions of Ilgin and Tuncbilek lignites were 14.8%, 22.9%, 24.6%, 26.8% and 17.3%, 268%, 29.4%, 31.3% at 11.8, 15.1, 20.0, 27.5 MPa runs, respectively. Extracts recovered from SFEs were fractionated into petroleum ether solubles and benzene solubles by solvent extraction. Petroleum ether solubles were fractionated into hexane, benzene, methanol and tetrahydrofuran eluats. Benzene solubles were separated into phenols + acids, bases and neutrals fractions.