Chen Yunzhu, Sun Hongjuan, Peng Tongjiang, Ding Wenjin, Yin Hongmei
Key Laboratory of Ministry of Education for Solid Waste Treatment and Resource Recycle, Southwest University of Science and Technology, Mianyang 621010, China.
Department of Resources & Environment, Xichang University, Xichang 615000, China.
Materials (Basel). 2024 Aug 22;17(16):4152. doi: 10.3390/ma17164152.
The expansion of vermiculite using microwave irradiation is an environmentally friendly and efficient method that can enhance the material's adsorption performance. This study investigated the microwave irradiation of vermiculite with five different particle sizes (4/2/1/0.5/0.2 mm) and found that the adsorption capacity for Pb increased with larger particle sizes. The equilibrium adsorption capacity reached 15.98 mg/g at 4 mm, representing a 45.01% improvement compared to 0.2 mm. The pseudo-second-order kinetic model effectively described the adsorption kinetics. No significant differences were observed in the specific surface area and pore size distribution of all samples. Thermogravimetric quantitative analysis revealed that larger particle sizes retained interlayer water more effectively. As the particle size decreased, the interlayer water content generally showed a decreasing trend. Fourier-transform infrared spectroscopy analysis also indicated that the -OH groups in larger particle sizes exhibited higher stability. The results suggest that the high content and stability of -OH groups may be key factors in the enhanced adsorption performance for Pb. This provides new insights for the preparation of environmentally friendly adsorbent materials rich in hydroxyl groups.
利用微波辐射对蛭石进行膨化是一种环保且高效的方法，能够提高材料的吸附性能。本研究对五种不同粒径（4/2/1/0.5/0.2毫米）的蛭石进行微波辐射，发现对铅的吸附容量随粒径增大而增加。4毫米粒径时平衡吸附容量达到15.98毫克/克，相较于0.2毫米粒径提高了45.01%。准二级动力学模型有效地描述了吸附动力学。所有样品的比表面积和孔径分布未观察到显著差异。热重定量分析表明，较大粒径能更有效地保留层间水。随着粒径减小，层间水含量总体呈下降趋势。傅里叶变换红外光谱分析还表明，较大粒径中的-OH基团表现出更高的稳定性。结果表明，-OH基团的高含量和稳定性可能是铅吸附性能增强的关键因素。这为制备富含羟基的环保吸附材料提供了新的见解。
