固废基活性炭制备及其甲苯吸附机制研究

采用固废资源废弃活性炭为炭源前驱体，加入碱性助剂，经炭活化制备了再生活性炭（RAC, regeneration activatied carbon）样品，并进一步通过高铁酸钾改性处理，最终制备得到高性能VOCs吸附炭。同时通过SEM、RAMAN、FT-IR、XPS、动/静态吸附等表征设备，对改性前后的样品进行系统研究。研究结果表明，经过强氧化剂高铁酸钾改性后的RAC比表面积和孔体积提升了1.4倍，缺陷程度增强，表面含氧官能团含量显著增加。其中高铁酸钾改性24h后的样品对甲苯动态吸附性能最好（375.5mg/g），相比于原始样品RAC动态吸附量（192.8mg/g）增加了一倍；静态吸附测试结果发现RAC-6%K2FeO4+H2SO4-24h最大静态吸附量为796mg/g，表明高铁酸钾改性处理，能够显著增加RAC的VOCs吸附性能。此外，通过连续吸-脱附循环实验测试发现，第五次再生后的样品RAC-6%K2FeO4+H2SO4-24h仍然保持91%的吸附性能，具有良好的循环稳定性，对于工业VOCs废气的高效净化具有重要应用价值。

Preparation of solid waste-based activated carbon and its adsorption mechanism for toluene

Regenerated activated carbon (RAC) samples were prepared by carbon activation using waste activated carbon from solid waste resources as the carbon source precursor, adding alkaline additives, and further modified by potassium ferrate to finally prepare high-performance VOCs adsorption carbon. At the same time, the samples before and after modification were systematically studied through characterization equipment such as SEM, RAMAN, FT-IR, XPS, and dynamic/static adsorption. The results showed that the specific surface area and pore volume of the RAC after modification by the strong oxidant potassium ferrate increased by 1.4 times; the degree of defects was enhanced and the content of oxygen-containing functional groups on the surface increased significantly. Among them, the sample modified with potassium ferrate for 24h had the best toluene dynamic adsorption performance (375.5 mg/g), and the dynamic adsorption capacity was twice that of the original sample (192.8 mg/g); The static adsorption test found that the maximum adsorption capacity of RAC-6%K2FeO4+H2SO4-24h was 796 mg/g, which indicated that potassium ferrate modification treatment can significantly increase the VOCs adsorption performance of RAC. In addition, through consecutive toluene adsorption-desorption cycle tests, it was found that the sample RAC-6%K2FeO4+H2SO4-24h still maintained 91% adsorption activity after the fifth regeneration. This indicates that RAC-6%K2FeO4+H2SO4-24h has good cycle stability and great application value for the efficient purification of industrial VOCs waste gas.