Effects of CS<sub>2</sub> Solvent Extraction on Nanopores in Coal
Nian Si, Gaofeng Liu, Jia Lin, Ping Chang, Xiaoming Wang, Zhen Zhang, Huan Liu
Abstract
This study investigates the effects of the carbon disulfide (CS 2 ) extraction on nanopores of the anthracite samples. Comprehensive pore measurement techniques, including high-pressure mercury intrusion (HPMI), low-temperature nitrogen adsorption (LTNA), and low-temperature CO 2 adsorption (LTCA), were employed to analyze the variations of nanopore structure and fractal characteristics. After CS 2 extraction, the macropore average diameter and volume increase, while the macropore area and fractal dimension decrease, indicating the pore-enlarged and fractal dimension-reduced effects of CS 2 extraction on macropores. The pore-generated and fractal dimension-increased effects of CS 2 extraction on mesopores induce reduction in the average diameter and an increase in mesopore volume, area, and fractal dimension. The pore-enlarged and fractal dimension-reduced effects of CS 2 extraction on micropores cause an increase in the average diameter and reduction in micropore volume, area, and fractal dimension. These effects of CS 2 extraction on nanopore structure are conducive to enhancing CBM transport. This study can provide a theoretical basis on the chemical reservoir stimulation technique with CS 2 extraction.