乙撑胺改性生物炭螯合金属材料的磷吸附性能及解吸特性  

Adsorption and desorption characteristics of ethylenediamine modification of biochar chelating metal material

作　　者：杨佳芝 杨帆 钟艳霞[1,2,3] 贺婧 王世全 YANG Jiazhi;YANG Fan;ZHONG Yanxia;HE Jing;WANG Shiquan(Breeding Base for State Key Lab.of Land Degradation and Ecological Restoration in Northwestern China,Yinchuan,750021,China;Key Lab.of Restoration and Reconstruction of Degraded Ecosystems in Northwestern China of Ministry of Education,Yinchuan,750021,China;School of Ecology and Environment,Ningxia University,Yinchuan,750021,China)

机构地区：[1]西北土地退化与生态恢复国家重点实验室培育基地,银川750021 [2]西北退化生态系统恢复与重建教育部重点实验室,银川750021 [3]宁夏大学生态环境学院,银川750021

出　　处：《环境化学》2025年第2期605-616,共12页Environmental Chemistry

基　　金：国家自然科学基金(42277466);宁夏自然科学基金(2020A4C03052);清华大学-宁夏银川水联网数字治水联合研究院专项统筹重点项目(S KL-LOW-2022 TC2204);宁夏回族自治区重点研发计划项目(2023BEG02053);中国工程院战略研究与咨询项目(2023NXZD4)资助.

摘　　要：以芦苇秸秆制备的生物炭为载体,采用化学改性方法键合不同链长的乙撑胺,螯合不同金属制备了7种乙撑胺改性生物炭螯合金属材料.通过SEM、FTIR、元素分析进行了表征,比较了7种螯合材料对水中磷酸盐的吸附性能.结果表明,7种材料在1 min内均可达到平衡吸附量的90%.Al/TEPA-BC的吸附效果最佳,pH为6时吸附量最高;7种吸附剂对磷酸盐的吸附均符合Langmuir等温吸附模型,在材料表面积为2.286 m^(2)·g^(-1)的情况下,吸附性能最佳的Al/TEPA-BC的理论最大吸附量达到了9.53 mg·g^(-1);吸附行为均符合准二级速率模型;当磷酸盐初始浓度为15 mg·L^(-1),pH=6,投加量为0.1 g,温度为25℃时,Al/TEPA-BC对磷酸盐的吸附量可达到7.11 mg·L^(-1).Cl^(−)、SO_(4)^(2−)、NO_(3)^(−)共存时,Al/TEPA-BC对磷酸盐的选择性吸附为93.4%.推测其吸附机理以静电作用和配位作用为主.Biochar,prepared from reed straw,was used as a carrier to synthesize seven ethylenediamine-modified biochar chelating metal materials with different chain lengths of ethylenediamine and different metals through chemical modification.The materials were characterized by SEM,FTIR,and elemental analysis,and their adsorption performance for phosphates in water was compared.The results showed that all seven materials reached 90%of the equilibrium adsorption capacity within 1 minute.Among them,Al/TEPA-BC exhibited the best adsorption performance,with the highest adsorption capacity at pH 6.The adsorption of the 7 adsorbents for phosphate complied with the Langmuir isotherm adsorption model.With a material surface area of 2.286 m^(2)·g^(-1),the theoretical maximum adsorption capacity of the best performing Al/TEPA-BC reached 9.87 mg·g^(-1).The adsorption behavior followed a pseudo-second order rate model.When the initial concentration of phosphate was 15 mg·L^(-1),pH was 6,the dosage was 0.1 g,and the temperature was 25℃,the adsorption capacity of Al/TEPA-BC for phosphate reached 7.11 mg·L^(-1).When Cl^(−),SO_(4)^(2−),and NO_(3)^(−)coexisted,the selective adsorption of Al/TEPA-BC for phosphate was 93.4%.It is speculated that the adsorption mechanism is mainly attributed to electrostatic and coordination interactions.

关 键 词：乙撑胺改性 生物炭螯合材料 磷酸盐 吸附 解吸 

分 类 号：X-1[环境科学与工程] O6[理学—化学]