Novel sodium silicate/polymer composite gels for the prevention of spontaneous combustion of coal

Xiaofeng Ren; Xiangming Hu; Di Xue; Yongsheng Li; Zhiang Shao; Hao Dong; Weimin Cheng; Yanyun Zhao; Lin Xin; Wei Lu

doi:10.1016/j.jhazmat.2019.03.041

Novel sodium silicate/polymer composite gels for the prevention of spontaneous combustion of coal

J Hazard Mater. 2019 Jun 5:371:643-654. doi: 10.1016/j.jhazmat.2019.03.041. Epub 2019 Mar 9.

Authors

Xiaofeng Ren¹, Xiangming Hu², Di Xue¹, Yongsheng Li¹, Zhiang Shao¹, Hao Dong¹, Weimin Cheng³, Yanyun Zhao⁴, Lin Xin¹, Wei Lu¹

Affiliations

¹ College of Mining and Safety Engineering, Shandong University of Science and Technology, Qingdao, Shandong 266590, China; State Key Laboratory of Mining Disaster Prevention and Control Co-found by Shandong Province and the Ministry of Science and Technology, Shandong University of Science and Technology, Qingdao, Shandong 266590, China.
² College of Mining and Safety Engineering, Shandong University of Science and Technology, Qingdao, Shandong 266590, China; State Key Laboratory of Mining Disaster Prevention and Control Co-found by Shandong Province and the Ministry of Science and Technology, Shandong University of Science and Technology, Qingdao, Shandong 266590, China; College of Resources and Environmental Engineering, Binzhou University, Binzhou, Shandong 256603, China. Electronic address: xiangming0727@163.com.
³ College of Mining and Safety Engineering, Shandong University of Science and Technology, Qingdao, Shandong 266590, China; State Key Laboratory of Mining Disaster Prevention and Control Co-found by Shandong Province and the Ministry of Science and Technology, Shandong University of Science and Technology, Qingdao, Shandong 266590, China; College of Resources and Environmental Engineering, Binzhou University, Binzhou, Shandong 256603, China.
⁴ College of Chemical and Environmental Engineering, Shandong University of Science and Technology, Qingdao, Shandong 266590, China.

PMID: 30889461
DOI: 10.1016/j.jhazmat.2019.03.041

Abstract

Novel gel materials are proposed for fire prevention and extinction in coal mines, where spontaneous combustion of coal continues to pose a significant risk. Cationic polyacrylamide (CPAM), anionic polyacrylamide (HPAM), and carboxymethyl cellulose (CMC) were each introduced separately into a sodium silicate (WG) gel, to obtain three gels labeled as CPAM/WG, HPAM/WG, and CMC/WG. A crosslinking agent, aluminum citrate, was subsequently added to the HPAM/WG and CMC/WG gels to afford two novel interpenetrating network hydrogels, HPAM-Al³⁺/WG and CMC-Al³⁺/WG, respectively. Among the various gels, the HPAM-Al³⁺/WG hydrogel exhibits the best seepage capacity, water retention capacity, compressive strength, and inhibition characteristics, which effectively resolve the post-water-loss cracking and pulverization problems commonly associated with inorganic consolidated silica gels. The microstructures of all the gels were investigated by scanning electron microscopy and their inhibitory effects on the oxidation of hydroxyl and methylene groups in coal at high temperatures were analyzed by Fourier transform infrared spectroscopy. Elemental mapping by energy dispersive X-ray spectroscopy indicated that the inorganic silica gel blends uniformly with the polymeric gel. Fire extinction experiments indicated that the HPAM-Al³⁺/WG gel reduces the fire-source temperature, heat radiation, and CO generation. Thus, the HPAM-Al³⁺/WG gel is an ideal fire prevention and extinction material.

Keywords: Fire prevention; Inhibition; Polyacrylamide; Sodium silicate gel; Water retention capacity.