Coliquefaction of Elbistan lignite and biomass under catalytic conditions

In this study, Elbistan lignite and various wastes (organic fertilizer, waste plastic and waste tea) were liquefied under catalytic conditions in an inert atmosphere. Red mude, tetralin and distilled water was used as a catalyst and solvent respectively. The liquefaction studies were carried out under catalytic conditions in the catalyst concentration of 3%-12%, solvent/solid ratio range of 1/1-9/1, reaction time of 30-120 minutes, waste/lignite ratio of 1/1-1/6 and at temperatures 350 oC and 400 oC. Stirring speed and initial nitrogen pressure were kept constant at 400 rpm and 20 bar respectively. At the end of liquefaction process, the soluble liquefaction products were separated by successive solvent extraction to preasphaltene, asphaltene and oils. Oils obtained by liquefaction were qualitatively and quantatively analyzed by G.C.-M.S. Results represented that a higher total and oil+gas conversions were obtained in coliquefaction of Elbistan lignite with wastes in comparision with liquefaction of that without wastes. Fertilizer was selected as an optimum waste. Oil+gas conversions under catalytic contions were higher than non-catalytic conditions. By considering total and oil+gas conversions, the optimum process parameters were found to be 9% of catalyst concentration, liquid/solid ratio of 3/1, reaction time of 60 minutes, waste/lignite ratio of 1/1 and at the reaction temperature of 400 oC. Results attained by G.C.-M.S. analysis of oils, obtained by liquefaction studies, showed that oils were mainly composed of naphthalene and derivatives, tetralin and derivatives, benzene and derivatives, cyclohexane, methyl-cyclopentane, azulene, butylated-hydroxytoluen and straight chain hydrocarbon compounds.