School of Chemical and Environmental Engineering, China University of Mining & Technology (Beijing), Beijing, 100083, PR China; Department of Civil and Environmental Engineering, University of Alberta, Edmonton, AB, T6G 2W2, Canada.
School of Chemical and Environmental Engineering, China University of Mining & Technology (Beijing), Beijing, 100083, PR China.
J Hazard Mater. 2019 Feb 15;364:317-324. doi: 10.1016/j.jhazmat.2018.10.031. Epub 2018 Oct 15.
The abundance of natural porous minerals and their low cost make them the potential adsorbents for VOCs (volatile organic compounds). In this paper, three natural minerals (diatomite, stellerite and vitric tuff) and their corresponding acid-treated minerals were used as adsorbents. The adsorption performances of minerals were investigated by the adsorption breakthrough curves of VOCs. The results indicated that the properties of organic compounds such as boiling point and polarity and the surface area and pore volume of minerals had obvious effects on the adsorption of VOCs over minerals. Increasing adsorption temperature and relative humidity would have negative effects on the VOC adsorption of minerals. The adsorption capacity of 2-heptanone over acid stellerite decreased by 7.2% as the temperature rose from 25°C to 45°C. The adsorption capacity of acid stellerite for 2-heptanone reduced by 60.9% when relative humidity increased from 0% to 75%. Minerals were tested for five adsorption-regeneration cycles to study the reusability. Better fittings of Thomas model, pseudo-first order kinetics model, and Freundlich model were showed in fitting the adsorption. Overall, porous minerals with high specific surface area and pore volume have promising prospect in VOCs adsorption.
天然多孔矿物资源丰富且成本低廉，它们有望成为 VOCs（挥发性有机化合物）的潜在吸附剂。本文使用三种天然矿物（硅藻土、辉绿岩和火山凝灰岩）及其相应的酸处理矿物作为吸附剂。通过 VOCs 的吸附穿透曲线研究了矿物的吸附性能。结果表明，有机化合物的性质（如沸点和极性）以及矿物的表面积和孔体积对 VOCs 在矿物上的吸附有明显影响。增加吸附温度和相对湿度会对矿物的 VOC 吸附产生负面影响。当温度从 25°C 升高到 45°C 时，酸处理后的辉绿岩对 2-庚酮的吸附容量下降了 7.2%。当相对湿度从 0%增加到 75%时，酸处理后的辉绿岩对 2-庚酮的吸附容量降低了 60.9%。对矿物进行了五次吸附-再生循环测试，以研究其可重复使用性。Thomas 模型、准一级动力学模型和 Freundlich 模型对吸附的拟合更好。总的来说，具有高比表面积和孔体积的多孔矿物在 VOCs 吸附方面具有广阔的前景。
