College of Safety Science and Engineering, Xi'an University of Science and Technology, Xi'an 710054, Shaanxi, China.
Key Laboratory of China Western Mine and Hazard Prevention, Ministry of Education of China, Xi'an 710054, Shaanxi, China.
Environ Sci Pollut Res Int. 2024 Sep;31(43):55597-55609. doi: 10.1007/s11356-024-34893-4. Epub 2024 Sep 6.
To realize the resource utilization of solid waste (coal slime) and further the dual carbon goals, utilizing coal slime and coal ash as adsorbates for CO capture is crucial. This study employed low-temperature N adsorption, low-pressure CO adsorption, X-ray diffraction, X-ray fluorescence, and isothermal adsorption tests to assess coal slime and coal ash's pore/mineral composition characteristics. Subsequently, the influence on CO adsorption was analyzed to reveal the CO adsorption mechanisms of pores and clay minerals, and CO molecule adsorption behavior. The results showed that: (1) ashing led to reductions in total pore volume, specific surface area, micropore volume, and micropore specific surface area, accompanied by substantial decreases in micropores and mesopores; (2) ashing generated high-temperature stable mineral species, including quartz, andalusite, hematite, and gypsum, while all calcite decomposed into CaO; (3) coal slime exhibited greater CO adsorption capacity than coal ash, influenced by pore structure and clay minerals; (4) the adsorption behavior of coal slime and coal ash likely aligns with micropore filling theory, suggesting CO is adsorbed within the 0.30-1.47 nm pore structure. This research contributes to optimizing coal by-product utilization in mining areas and exploring adsorbate materials for CO sequestration in abandoned goaf.
为实现固体废物（煤泥）的资源利用和进一步推进双碳目标，利用煤泥和粉煤灰作为 CO 捕集的吸附剂至关重要。本研究采用低温 N 吸附、低压 CO 吸附、X 射线衍射、X 射线荧光和等温吸附试验，评估了煤泥和粉煤灰的孔/矿物组成特征。随后，分析了其对 CO 吸附的影响，以揭示孔和粘土矿物以及 CO 分子吸附行为的 CO 吸附机理。结果表明：（1）灰化导致总孔体积、比表面积、微孔体积和微孔比表面积减少，同时微孔和中孔大量减少；（2）灰化产生了高温稳定的矿物种类，包括石英、蓝晶石、赤铁矿和石膏，而所有方解石都分解为 CaO；（3）煤泥的 CO 吸附能力大于粉煤灰，受孔结构和粘土矿物的影响；（4）煤泥和粉煤灰的吸附行为可能符合微孔填充理论，表明 CO 被吸附在 0.30-1.47nm 的孔结构内。本研究有助于优化矿区煤副产品的利用，并探索废弃采空区中 CO 封存的吸附剂材料。
