Analysis of structure and pyrolysis and gasification characteristics of lignite after tetrahydronaphthalene treatment

Dewatering and upgrading of Inner Mongolia Xilingol lignite in non-polar solvent (tetrahydronaphthalene, THN) were carried out in a miniature autoclave. The changes of organic functional groups in coal samples at different dewatering temperature were analyzed based on Fourier-transform infrared (FT-IR) analyzer. The fitting calculation for FT-IR spectra has been carried out. Besides, a semi-quantitative analysis for characteristics of chemical structure change was presented. The pyrolysis and gasification reactivity and distributive rules of gas phase product during pyrolysis and gasification of coal with various dewatering temperature were carried out by means of thermogravimetric analysis (TG) and a bench-scale fixed-bed pyrolysis reactor. The kinetic parameters of coal samples were calculated within the range of the maximum weight loss rate. The results showed that the