Enhancing understanding of anionic surfactant adsorption mechanism and hydrophilic modification of bituminous coal for effective dust suppression

• Published in: Surfaces and interfaces 2024-03, Vol.46, p.103948, Article 103948
• Main Authors: Liu, Huajun, Li, Ruoxi, Nie, Wen, Bao, Qiu, Niu, Wenjin, Tian, Qifan, Zhang, Xiaohan
• Format: Article
• Language: English
• Subjects: Anionic surfactant; Surface adsorption; van der Waals effect
• ISSN: 2468-0230; 2468-0230
• DOI: 10.1016/j.surfin.2024.103948

The large amount of coal dust generated by mechanized coal mining poses hazards such as coal mine explosions, coal worker pneumoconiosis, and atmospheric pollution. Spray dust suppression is widely employed as a coal dust control technology in the mining process, with anionic surfactants commonly used as highly effective wetting and enhancing agents. However, the application process lacks theoretical guidance on the interaction mechanism between anionic surfactants and coal dust. This study aims to investigate the adsorption mechanism between anionic surfactants and coal dust surfaces, focusing on two specific surfactants: sodium dioctyl sulfosuccinate (AOT) and sodium dodecyl sulfate (SDS). Both surfactants possess the same hydrophilic group but differ in their tail chain groups. Through a comprehensive analysis, this research provides insights into the essential properties and characteristics of AOT and SDS adsorption on bituminous coal. Static adsorption experiments revealed that AOT exhibited a higher maximum adsorption capacity (Qe) on coal dust compared to SDS. Scanning electron microscopy and particle size characterization analysis demonstrated AOT's notable tendency to cluster coal dust particles. Fourier-transform infrared spectroscopy and X-ray photoelectron spectroscopy investigations confirmed a significant hydrophilic modification induced by AOT on the coal dust surface. Quantum chemistry calculations revealed that Van der Waals adsorption played a fundamental role in the interaction between the AOT and SDS tail chains and the coal surface. The double tail chain structure of AOT contributed to a more stable and stronger adsorption configuration with coal molecules. These findings provide valuable theoretical insights for the development and application of effective dust suppressants. [Display omitted]