摘要
以机械化学研磨法制备的Fe-EDTA聚合物为前驱体,开发了一种免液相浸渍的碳热法,来实现对多孔碳材料固载纳米零价铁.考察了Fe-EDTA聚合物碳化温度、与多孔碳的混合方式及质量比等因素对零价铁负载的影响.相比于传统液相浸渍+碳热法制备的零价铁/多孔碳复合材料,免浸渍碳热法所得复合材料的表面积大、吸附位点多、零价铁粒径小且均匀.以所制备的零价铁/多孔碳复合材料为催化剂/吸附剂,用于水样中甲基橙、Cr(Ⅵ)及污水中COD的去除.结果表明,与液相浸渍+碳热法制备的复合材料相比,免浸渍碳热法制备的零价铁/多孔碳复合材料的零价铁具有纳米级粒径,因此拥有超高的活性,可更有效地吸附、还原及氧化降解污染物,且表现出良好的重复利用性.动态装柱实验表明,该复合材料在较长时间内可以稳定去除污水中的COD.
By using mechanochemically prepared Fe-EDTA polymers as precursors, an impregnation-free carbothermal method is developed to realize the immobilization of nanoscaled zero-valent iron(nZVI) onto porous carbon materials. The effects of carbonization temperature,mixing modes and mass ratio of Fe-EDTA polymer with porous carbon on the loading of nZVI are investigated. Compared with nZVI/porous carbon composites synthesized with traditional liquidphase impregnation combined with carbothermal method(nZVI/coke(impregnation)), the composites prepared by impregnation-free carbothermal method(nZVI/coke) have larger surface area, more adsorption sites, and smaller particle size of nZVI with uniform distribution. The obtained nZVI/coke composites are used as catalysts/adsorbents for the removal of methyl orange, Cr(VI) and COD from water samples. The results demonstrate that nZVI/coke composites prepared by impregnation-free carbothermal method can more efficiently adsorb, reduce or oxidative degrade pollutants due to the high activity of nanoscaled ZVI particles compared to nZVI/coke(impregnation). These materials also exhibited good reusability. The dynamic column experiment showed that the nZVI/porous carbon composites can continuously and efficiently remove COD from wastewater within several days.
作者
牛红云
吕宏洲
蔡亚岐
NIU Hongyun;LYU Hongzhou;CAI Yaqi(State Key Laboratory of Environmental Chemistry and Ecotoxicology,Research Center for Eco-Environmental Sciences,Chinese Academy of Sciences,Beijing,100085,China;State Key Laboratory of Environmental Criteria and Risk Assessment,Chinese Research Academy of Environmental Sciences,Beijing,100012,China)
出处
《环境化学》
CAS
CSCD
北大核心
2021年第12期3662-3671,共10页
Environmental Chemistry
基金
国家重点研发计划(2016YFA0203100)
北京市自然科学基金(8202046)资助。
