College of Environmental Science and Engineering, Hunan University, Changsha, 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control, Ministry of Education, Hunan University, Changsha, 410082, PR China.
College of Environmental Science and Engineering, Hunan University, Changsha, 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control, Ministry of Education, Hunan University, Changsha, 410082, PR China.
Chemosphere. 2019 May;222:184-194. doi: 10.1016/j.chemosphere.2019.01.128. Epub 2019 Jan 25.
Adsorption behaviors and mechanisms of metal endocrine disruptors (Pb, Cd, and Hg) by pyrogenic carbonaceous materials including engineered carbons (biochar and activated carbon) and carbon nanomaterials (multi-walled carbon nanotubes and graphene oxide) have been investigated by experimental and density functional theory (DFT) studies. The adsorption isotherms of metal endocrine disruptors on carbonaceous materials were better fitted by Langmuir models. The adsorption capacities were in the order as follows: GO > BC600 > BC300 > CNT > AC for Pb, GO > BC300 > AC > BC600 > CNT for Cd, and GO > BC300 ≥ AC > CNT > BC600 for Hg, respectively. The DFT-computed binding energy (kcal/mol) of different oxygen-containing functional groups with metal endocrine disruptors followed the orders: (ⅰ) CMCOCPb (-136.70) > CM-COO-Pb (-91.58) > CMCOPb (-33.57) > CMOHPb (-4.69), (ⅱ) CM-COO-Cd (-45.91) > CMCOCCd (-4.49) > CMOHCd (-3.68) > CMCOCd (1.08), (ⅲ) CM-COO-Hg (-25.51) > CMCOCHg (-3.58) > CMOHHg (-0.63) > CMCOHg (0.23). And COC has the highest binding energy for Pb, whereas COC has much lower binding energy for Cd and Hg. Comprehensively considering DFT calculations, competitive adsorption results and the cost analysis, this work may provide insights into the design of selective adsorbent for specific contaminant.
利用实验和密度泛函理论（DFT）研究了包括工程碳（生物炭和活性炭）和碳纳米材料（多壁碳纳米管和氧化石墨烯）在内的热解碳质材料对金属内分泌干扰物（Pb、Cd 和 Hg）的吸附行为和机制。金属内分泌干扰物在碳质材料上的吸附等温线更符合朗缪尔模型。吸附容量的顺序如下：GO>BC600>BC300>CNT>AC 对于 Pb，GO>BC300>AC>BC600>CNT 对于 Cd，GO>BC300≥AC>CNT>BC600 对于 Hg。不同含氧官能团与金属内分泌干扰物的 DFT 计算结合能（kcal/mol）的顺序为：（i）CMCOCPb（-136.70）>CM-COO-Pb（-91.58）>CMCOPb（-33.57）>CMOHPb（-4.69），（ii）CM-COO-Cd（-45.91）>CMCOCCd（-4.49）>CMOHCd（-3.68）>CMCOCd（1.08），（iii）CM-COO-Hg（-25.51）>CMCOCHg（-3.58）>CMOHHg（-0.63）>CMCOHg（0.23）。对于 Pb，COC 具有最高的结合能，而对于 Cd 和 Hg，COC 的结合能则低得多。综合考虑 DFT 计算、竞争吸附结果和成本分析，这项工作可能为设计针对特定污染物的选择性吸附剂提供了思路。
