Lu Wei, Su Hao, Qi Guansheng, Zhang Huilin, Wang Mingjun, Hu Xiangming
College of Safety and Environmental Engineering, Shandong University of Science and Technology, Qingdao 266590, China.
School of Safety Science and Engineering, Anhui University of Science and Technology, Huainan 232001, China.
Langmuir. 2022 Sep 20;38(37):11382-11391. doi: 10.1021/acs.langmuir.2c01667. Epub 2022 Sep 7.
Goaf filling is an effective method of preventing goaf disasters in mines. If the filling material can mineralize and absorb a large amount of CO, then the goaf will provide a huge amount of space for carbon storage, which will help to achieve carbon peaking and carbon neutrality. The purpose of this article is to prepare a kind of porous particle with high porosity and a large specific surface area that can be used to fill the mined-out area and adsorb a large amount of CO by using the mineralized solid waste as the aggregate. Taking the compressive strength and CO adsorption capacity as the objective function, a chemical foaming method and an orthogonal experiment were used to determine the optimal ratio of porous particles. The results showed that when the masses of carbide slag, oleic acid, cetyltrimethylammonium bromide, sodium hypochlorite, and water were 19.5, 0.3, 0.07, 1.35, and 15 g, respectively, the pore sizes of the prepared porous particles had a gradient distribution, i.e., micropores, mesopores, and macropores accounted for 18.75, 80.93, and 0.32%, respectively. In addition, the compressive strength reached 79.4 N, and the static CO adsorption capacity was 117.43 cm/g. The superimposed calculation of the adsorption capacity and mineralization capacity showed that 1 ton of solid waste can theoretically store approximately 0.66 ton of CO. The pseudo-first-order kinetic model can well fit the adsorption process of an adsorbent for CO, which proves that the adsorption process of adsorbent for CO is a physical adsorption mechanism. The porous particles prepared based on solid waste are harmless and simple in the preparation process. They can fill the underground space of mines after adsorbing CO and realize the integration of solid waste utilization, carbon storage, and underground space disaster management, with significant social, economic, and ecological benefits.
