Yang Yuxuan, Zhong Zhaoping, Du Haoran, Li Qian, Zheng Xiang, Qi Renzhi, Ren Pengkun
Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University, Nanjing 210096, China.
Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University, Nanjing 210096, China.
J Hazard Mater. 2024 Feb 5;463:132885. doi: 10.1016/j.jhazmat.2023.132885. Epub 2023 Oct 28.
Na/K/Mg/Ca expansion-modified vermiculite and calcination expansion (700 °C, 800 °C and 900 °C)-modified vermiculite (700-Mg-V, 800-Mg-V and 900-Mg-V) were prepared as additives to control the emission of five heavy metals (Zn, Cr, Cu, Pb, and Cd) during the pyrolysis of municipal sewage sludge, paper mill sludge, municipal domestic waste, and aged refuse. Mg-Modified vermiculite obtained via thermally activated calcination at 800 °C retained 65% of heavy metals from all raw materials at 450 °C. Zn, Cr, and Cu retained nearly 90%. Although modified vermiculite could reduce the ecological risk, Cd had an ecological risk level higher than Zn, Cr, Cu, and Pb. The fine textural properties, laminated morphology, and expansion capacity of modified vermiculite were positively correlated with its retention of heavy metals. Heavy metals interacted with the (002) surface of vermiculite, and the reactions were mainly concentrated near the 17-O and surrounding atoms. The heavy-metal monomers were less capable of binding to the (002) surface of vermiculite than the oxides and chlorides of heavy metals. The effect of heavy-metal oxides and chlorides binding to the (002) surface of vermiculite was related to heavy metals.
钠/钾/镁/钙膨胀改性蛭石以及煅烧膨胀（700℃、800℃和900℃）改性蛭石（700 - Mg - V、800 - Mg - V和900 - Mg - V）被制备用作添加剂，以控制城市污水污泥、造纸厂污泥、城市生活垃圾和陈腐垃圾热解过程中五种重金属（锌、铬、铜、铅和镉）的排放。在800℃通过热活化煅烧获得的镁改性蛭石在450℃时能保留所有原材料中65%的重金属。锌、铬和铜的保留率接近90%。虽然改性蛭石可以降低生态风险，但镉的生态风险水平高于锌、铬、铜和铅。改性蛭石良好的纹理特性、层状形态和膨胀能力与其对重金属的保留呈正相关。重金属与蛭石的（002）表面相互作用，反应主要集中在17 - O及其周围原子附近。重金属单体与蛭石（002）表面结合的能力低于重金属的氧化物和氯化物。重金属氧化物和氯化物与蛭石（002）表面结合的效果与重金属有关。
