title: Physicochemical properties of chars at different treatment temperatures.
abstract: In this study, the physicochemical properties of the char of Indonesian SM coal following heat treatment at various temperatures were evaluated using X-ray photoelectron spectroscopy (XPS), Fourier-transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), and morphological and specific surface area analysis. Based on these analyses, heat treatment of coal was determined to be the most effective in increasing the coal rank. In the XPS analysis, the C-O and C-O-C groups and quaternary-N species were found to be of a lower grade coal when the pretreatment temperature decreased, meanwhile the C-C group and pyridinic species increased. In the FT-IR analysis, the collapse of the C-O and C-O-C group was observed due to the collapse of the ether group. In SEM and Brunauer-Emmett-Teller (BET) analysis, a decrease in the ether group was shown to be accompanied with the formation of micropores.
authors.affiliation: Department of Environmental Energy Systems Engineering, Graduate School of Kyonggi University, Iui-dong, Youngtong-ku, Suwon-si, Gyeonggi-do, Korea.
authors.forename: Sung Su
authors.initials: SS
authors.lastname: Kim
authors.forename: Youn Suk
authors.initials: YS
authors.lastname: Kang
authors.forename: Hyun Dong
authors.initials: HD
authors.lastname: Lee
authors.forename: Jae Kwan
authors.initials: JK
authors.lastname: Kim
authors.forename: Sung Chang
authors.initials: SC
authors.lastname: Hong
mesh_terms: D003031:Coal / Q000032:analysis*; D006358:Hot Temperature; D056951:Photoelectron Spectroscopy
chemical_list: D003031:Coal