Investigation of Swelling Properties and Liquefaction of Solid Fuels

Abstract

In this study, the effect of various parameters on the swelling of Edirne Uzunköprü, Edirne Keşan Çanakkale Yeniçirpılar and Bursa Mustafa Kemal Paşa lignites was investigated. In the first part of the study, swelling processes were applied to the lignites. Swelling measurements were made in closed glass tubes using 10 different solvents. Swelling ratios of lignite samples treated with solvents were determined and the dependence of these ratios on the properties of the solvent was examined. In the second part, the original lignite samples, swollen with various solvents, were subjected to soxhlet extraction with THF and the liquid product yields obtained from each sample were determined. Then, the same samples were extracted with toluene under supercritical conditions, and the effects of temperature, pressure, and pre-expansion on the extract yield were investigated. Extract yields of lignite samples swollen with solvents such as THF, TBAH, DMSO, DMF, and EDA were found to be higher than those of other solvents. The common features of these solvents are that they have atoms containing unpaired electrons such as N, O, etc. In addition, it was thought that the high extract yields of solvents with a large and positive difference in the number of donors and acceptors may be related to the breaking of the cross-links in the lignites by the solvent.