竹炭负载氧化锌对Cr(Ⅵ)的吸附性能和机理  

Adsorption Capacity and Mechanism of ZnO Loading Bamboo Biochar for Cr(Ⅵ)

作　　者：邓华[1,2] 张俊渝 黄瑞[1,2] 王威 胡乐宁[1,2] DENG Hua;ZHANG Junyu;HUANG Rui;WANG Wei;HU Lening(Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection(Guangxi Normal University),Ministry of Edncation,Guilin Guangxi 541006,China;College of Environment and Resources,Guangxi Normal University,Guilin Guangxi 541006,China)

机构地区：[1]珍稀濒危动植物生态与环境保护教育部重点实验室(广西师范大学),广西桂林541006 [2]广西师范大学环境与资源学院,广西桂林541006

出　　处：《广西师范大学学报（自然科学版）》2023年第1期131-142,共12页Journal of Guangxi Normal University:Natural Science Edition

基　　金：国家自然科学基金(41301343);珍稀濒危动植物生态与环境保护教育部重点实验室研究基金(ERESEP2021Z15)。

摘　　要：本文以竹制生物炭为原材料,通过共沉淀法负载氧化锌制备锌改性生物炭(ZnBC)。通过批量实验探究ZnBC对废水中Cr(Ⅵ)的吸附性能,采用SEM、XRD、FTIR和XPS等分析方法对吸附Cr(Ⅵ)前后的ZnBC进行表征。实验结果表明,在pH=7、反应时间720 min、反应温度298 K时,ZnBC对Cr(Ⅵ)的吸附效果最好。Cr(Ⅵ)的吸附结果符合拟二级(PSO)和Langmuir模型理论,表明吸附类型为化学吸附和单分子层吸附;通过Langmuir模型拟合得出的饱和吸附量为106.383 mg/g。共存离子实验表明,ZnBC对Cr(Ⅵ)有较好的选择吸附性。ZnBC对Cr(Ⅵ)的吸附机理主要包括光催化还原、官能团络合、阳离子-π以及沉淀作用。研究表明,ZnBC作为去除水溶液中Cr(Ⅵ)的吸附剂具有较大的应用潜力。Zn-modified biochar(ZnBC)was prepared from bamboo biochar by co-precipitation loading ZnO.The adsorption performance of ZnBC for Cr(Ⅵ)in wastewater was investigated by batch experiments.The ZnBC before and after adsorption was characterized by SEM,XRD,FTIR and XPS.The experimental results show that the adsorption of Cr(Ⅵ)by ZnBC is the best at pH=7,reaction time 720 min and reaction temperature 298 K.The adsorption results of Cr(Ⅵ)conform to the pseudo-second-order(PSO)and Langmuir model theory,indicating that the adsorption types are chemical adsorption and monolayer adsorption.The saturated adsorption capacity fitted by Langmuir model is 106.383 mg/g.The coexisting ion experiments show that ZnBC has good selective adsorption for Cr(Ⅵ).The adsorption mechanism of Cr(Ⅵ)by ZnBC mainly includes photocatalytic reduction,functional group complexation,cation-πand precipitation.The results show that ZnBC has great application potential as adsorbent for removing Cr(Ⅵ)from aqueous solution.

关 键 词：竹制生物炭 共沉淀法 氧化锌 Cr(Ⅵ) 吸附机理 

分 类 号：X522[环境科学与工程—环境工程]