The nanoscale pore characteristics of coking coals: Part 3 – Variations in pore characteristics of coking coals with various ranks

Key Laboratory for Chemical Metallurgy Engineering of Liaoning Province, University of Science and Technology Liaoning, Anshan, Liaoning 114051, China
wangqi8822@sina.com

Received: 26 May 2016
Accepted: 12 December 2016

Abstract

Low-temperature N₂ physisorption measurements were performed on six coking coal samples from different coal basin in China in order to investigate the variations in pore characteristics of coking coals with various ranks and gain insight into the possibility of the nanoscale pore characteristics being as new evaluation indexes for coking coals to supplement and perfect the quondam evaluation system. The experimental conditions and calculation methods were adopted as optimized in Part 1 and Part 2 of these series of articles [Cheng et al., Metall. Res. Technol. 114 (2017) 115; Cheng et al., Metall. Res. Technol. 114 (2017) 116]. Besides, the fractal dimension (D) calculated by the Frenkel–Halsey–Hill (FHH) method was also given. Three justifications were found, i.e. the complexity of pore structure including diverse types of pores and large variation of pore size distribution, regular variation of some structural parameters such as total and external specific surface areas, micropore volume and some parameters of the particular pore size, and significant difference of the parameter like average pore size calculated by the BJH method for samples with similar coal rank.