生物炭对含氢键供体染料的吸附性能及机理  

Adsorption performance and mechanism of biochar to dyes with H-donor

作　　者：邹致远 陈扬 龙鑫鑫 刘猛 郭送军 陈荣志 ZOU Zhiyuan;CHEN Yang;LONG xinxin;LIU Meng;GUO Songjun;CHEN Rongzhi(School of Resources,Environment and Materials,Guangxi University,530004,China;College of Resources and Environment,University of Chinese Academy of Sciences,100049,China)

机构地区：[1]广西大学资源环境与材料学院,南宁530004 [2]中国科学院大学资源与环境学院,北京100049

出　　处：《环境工程学报》2022年第10期3181-3191,共11页Chinese Journal of Environmental Engineering

基　　金：广东省环境资源利用与保护重点实验室基金项目(2020B1212060053);国家重点研发计划项目(2019YFC1906501);国家自然科学基金项目(21806166);中央高校基本科研业务费专项资金。

摘　　要：为确定染料有无氢键供体对生物炭吸附容量的影响及作用机理,制备了尿素/碳酸氢钾联合活化的玉米秸秆生物炭(KN-BC),考察其对于结构相似的亚甲基蓝(MB)与天青B(AB)的吸附容量差别及具体机制。对KNBC的表征结果表明,经处理后的生物炭疏松多孔,表面含氧官能团含量显著增加。吸附实验结果表明,Langmuir模型拟合的KN-BC对MB和AB的最大吸附量为2268.7 mg·g^(-1)和4368.5 mg·g^(-1),KN-BC对含有氢键供体的AB吸附性能更好。DFT计算与机理分析结果表明,氢键供体的存在使得单个污染物分子与生物炭可以同时形成氢键和π-π相互作用,两者的协同效应增强了π电子密度,显著提高了吸附效能。以上研究结果为预测生物炭对混合染料污水的吸附提供参考。To determine whether the H-donors on dyes affect the adsorption capacity of biochar,the corn straw biochar was prepared by the combined activation of potassium bicarbonate and urea(named KN-BC),and KNBC was used to adsorb the similar structure dyes of methylene blue(MB)and azure B(AB)to investigate the difference in adsorption capacities and underlying mechanisms.The characterizations revealed that KN-BC was highly porous,and the content of oxygen-containing functional groups increased significantly after activation.The batch experiments indicated that the maximum adsorption capacities to MB and AB in the Langmuir model reached 2268.7 mg·g^(-1)and 4368.5 mg·g^(-1),respectively.And higher adsorption capacity of KN-BC to AB with the H-donors occurred.DFT computation and analysis implied that the H-donor on dyes allows the co-existence of hydrogen bonding andπ-πinteraction between single dye molecular and KN-BC.The synergistic effect increased theπ-electron density and improved the adsorption capacity.This work can provide a reference for estimating mixed dye adsorption on biochar.

关 键 词：生物炭 吸附 氢键供体 氢键作用 Π-Π相互作用 协同效应 

分 类 号：X703.1[环境科学与工程—环境工程]