Fuel Processing Technology, Vol.104, 281-286, 2012
Co-liquefaction of coal and polypropylene or polystyrene in hot compressed water at 360-430 degrees C
The co-liquefaction of coal and polypropylene or polystyrene in hot compressed water was carried out in a 50 mL batch stainless steel autoclave reactor. The effects of the polymer ratios by weight (10-40%), reaction temperatures (360-430 degrees C), and reaction time (30-120 min) were investigated. The main products were analyzed qualitatively by Fourier transform infrared spectroscopy and high-performance liquid chromatography. The results showed that the synergistic effect was demonstrated and the polymer stimulated coal liquefaction as a hydrogen donor during co-liquefaction in hot compressed water. The reaction temperature was the critical factor because the process of oil and gas generating by hydro-cracking, ring-opening and hydrogenation clearly occurred above 400 degrees C and the conversion and yield of oil and gas reached a maximum of 75.92% and 69.11% at 420 degrees C, respectively. The phase behavior during co-liquefaction in a fused-silica capillary reactor was recorded by a microscope during the heating and cooling processes, demonstrating that polypropylene melted to form a liquid phase as the reaction medium and hydrogen donor during co-liquefaction. (C) 2012 Elsevier B.V. All rights reserved.