Synergy of chelating agents and surfactants on the wettability and pore structure of coal dust: Experimental study and molecular simulation

• Published in: Chemical engineering journal (Lausanne, Switzerland : 1996) Switzerland : 1996), 2024-12, Vol.502, p.157954, Article 157954
• Main Authors: Nie, Wen, Zhang, Xiaohan, Niu, Wenjin, Bao, Qiu, Tian, Qifan, Li, Ruoxi, Shi, Chenfeng, Tong, Ke, Zhang, Zhihui, Lian, Jie
• Format: Article
• Language: English
• Subjects: Chelating agent; Coal dust pollution; Dustfall agent; Mechanistic study; Wetting adsorption
• ISSN: 1385-8947
• DOI: 10.1016/j.cej.2024.157954

•Developed GLDA-AES, an efficient, eco-friendly multifunctional dust-reducing agent.•The wetting effect of dust removal agent exceeds that of traditional surfactants.•GLDA molecules dissolve minerals in coal to improve wettability.•The co-wetting mechanism of GLDA-AES was studied on the microscopic scale. To reduce the hazards of coal dust pollution to miner health and the environment, and to realize efficient wetting and settling of coal dust, this paper evaluates the wettability of tetrasodium glutamate diacetate (GLDA)–aliphatic alcohol polyoxyethylene ether sodium sulfate (AES), hereafter termed G–A, by selecting the surfactant through macroscopic experiments and microscopic simulations. With the help of molecular simulation to study the synergistic mechanism of the surfactants and chelating agents, the functional group changes and mesoscopic modification of coal dust particles were evaluated in combination with characterization experiments. Comprehensive analysis showed that the G-A solution had the best wettability with a low surface tension of 22.77 mN/m, the diffusion rate of the solution increased to 1.25°/s, and the contact angle with the coal dust decreased to 18° within 12 s. After infiltration, the median particle size of coal dust reached 38.140 μm, which increased by 148 %. The pores and slits on the surface of the coal dust particles are further increased, providing surfactants with more extensive adsorption sites, and the proportion of hydrophilic groups on the surface of coal increased by 8.42 %, with the consequent improvement of wettability. This study provides a theoretical basis for the research and development of more environmentally friendly and efficient dust reducing agents in the field of spray dust reduction.