炭基菌剂促进Cr(Ⅵ)还原和Cr(Ⅲ)固定的协同效能及机制研究  

Study of Synergistic Effect and Mechanism of Biochar Based Bacterial Agent in Promoting the Reduction of Cr(Ⅵ)and the Fixation of Cr(Ⅲ)

作　　者：陈友媛[1,2,3] 李浩 刘乐成 寇晗 王磊 Chen Youyuan;Li Hao;Liu Lecheng;Kou Han;Wang Lei(College of Environmental Science and Engineering,Ocean University of China,Qingdao 266100,China;Shandong Provincial Key Laboratory of Marine Environment and Geological Engineering,Ocean University of China,Qingdao 266100,China;Key Laboratory of Marine Environment and Ecology,Ministry of Education,Ocean University of China,Qingdao 266100,China;North China Municipal Engineering Design&Research Institute Limited Company,Tianjin 300000,China)

机构地区：[1]中国海洋大学环境科学与工程学院,山东青岛266100 [2]中国海洋大学山东省海洋环境地质工程重点实验室,山东青岛266100 [3]中国海洋大学海洋环境与生态教育部重点实验室,山东青岛266100 [4]中国市政工程华北设计研究总院有限公司,天津300000

出　　处：《中国海洋大学学报(自然科学版)》2025年第5期128-137,共10页Periodical of Ocean University of China

基　　金：国家自然科学基金青年基金项目(42207060);中国博士后科学基金项目(2022M722980)资助。

摘　　要：微生物还原法在Cr(Ⅵ)污染的修复中发挥着重要的作用,但是存在修复效率低以及微生物流失的问题。本研究以水稻壳为原料制备了胺基改性生物炭(PBC),在其表面负载铬还原菌制成炭基菌剂(MPBC),并研究了PBC和铬还原菌对Cr(Ⅵ)还原和Cr(Ⅲ)固定的协同效果及机制。结果显示,PBC表面吸附的微生物数量是原始生物炭的4.3倍,有效减少了微生物的流失。Cr(Ⅵ)去除实验结果表明,铬还原菌、PBC和MPBC在实验的前6 h对Cr(Ⅵ)去除速率分别为1.6、5.9和11.7 mg·L^(-1)·h^(-1),PBC和铬还原菌对铬的去除表现出较强的协同效应,协同系数为49.6%。产物分析表明,75.9%的铬(Cr)被固定到MPBC表面,MPBC的XPS分析显示MPBC表面主要固定了Cr(Ⅲ)。炭基菌剂去除Cr的路径为MPBC的胺基官能团将Cr(Ⅵ)捕获,有利于菌剂还原Cr(Ⅵ),并促进胞外铬还原酶的释放和Cr(Ⅵ)的还原,然后通过胺基络合作用和胞外聚合物将Cr(Ⅲ)固定,从而增强了胺基改性生物炭和铬还原菌对铬污染的协同修复能力。本研究为在铬污染环境中同时实现Cr(Ⅵ)还原和Cr(Ⅲ)固定提供了新的思路。Microbial reduction plays an important role in the remediation of Cr(Ⅵ)pollution,but there are problems of low efficiency and microbial loss.This study developed an amine-modified biochar(PBC)from rice husks,onto which Cr(Ⅵ)reducing bacteria were loaded to create a microbial biochar composite(MPBC).The synergistic effects and mechanisms of PBC and Cr(Ⅵ)reducing bacteria on the reduction of Cr(Ⅵ)to Cr(Ⅲ)and the immobilization of Cr(Ⅲ)were investigated.Results indicated that the quantity of adsorbed microbes on the PBC surface was 4.3 times that on the original biochar,significantly reducing microbial loss.The experimental results for Cr(Ⅵ)removal show that the removal rates of chromium-reducing bacteria,PBC,and MPBC in the first 6 hours of the experiment were 1.6,5.9,and 11.7 mg·(L·h)^(-1),respectively,demonstrating a strong synergistic chromium removal effect between PBC and the bacteria,with a synergy coefficient of 49.6%.Product analysis revealed that 75.9%of chromium(Cr)was immobilized on the MPBC surface,with XPS analysis of MPBC confirming the predominance of Cr(Ⅲ)fixation.The pathway for Cr removal by the biochar composite involves the amino functional groups of MPBC capturing Cr(Ⅵ),facilitating the reduction of Cr(Ⅵ)by the microbial biochar composite,and promoting the release of extracellular chromium reductase,and reducing Cr(Ⅵ).The immobilization of Cr(Ⅲ)is achieved through amino complexation and extracellular polymeric substances,thereby enhancing the synergistic remediation capability of amine-modified biochar and Cr(Ⅵ)reducing bacteria for chromium contamination.This study offers a novel approach for the simultaneous reduction of Cr(Ⅵ)and immobilization of Cr(Ⅲ)in chromium-contaminated environments.

关 键 词：生物炭 胺基改性 铬还原菌 还原 协同效应 

分 类 号：X131.3[环境科学与工程—环境科学]