Thermoplasticity and Oxidative Treatment of Coal Liquefaction Residue Obtained from NEDOL 1t/d PSU

Abstract

Themoplastic property of liquefaction residue produced at NEDOL lt/d Process Supporting Unit using Wandoan and Wyoming coals was studied by Gieseler plastometer under atmospheric and elevated pressure. Effect of air oxidation on thermoplasticity was also investigated. Gieseler fluidity of residue was successfully reduced to zero by air oxidation at 150°C. Pressure dependency of fluidity of oxidized residue was different from that of caking coal. Fluidity was more reduced under higher pressure. Photoacoustic FT-IR spectra were measured for oxidized residues. Oxidation of residues was also observed in-situ by diffuse reflectance FT-IR spectrometer equipped with controlled environment chamber. IR spectra obtained showed that oxidation reaction of residue seemed to be similar to that of coal. Increase in absorption at around 1700 and 3400cm^-1 along with decrease in absorption at 2800 to 3050cm^-1 was observed as oxidation reaction proceeds, indicating formation of carbonyl and hydroxyl groups and dehydrogenation from methylene group mainly in aliphatic compounds.