天然有机质和水铁矿协同促进微生物还原固定Cr(Ⅵ)性能和机理研究  

Synergistic enhancement of microbial reduction of Cr(Ⅵ)by natural organic matter and ferrihydrite:Performance and mechanism

作　　者：王亚华 陈海 王茜茜 李玉腾 袁庆科 周添红[3,4] 张鉴达 孟颖 栾富波 WANG Yahua;CHEN Hai;WANG Qianqian;LI Yuteng;YUAN Qingke;ZHOU Tianhong;ZHANG Jianda;MENG Ying;LUAN Fubo(Key Laboratory of Drinking Water Science and Technology,Research Center for Eco-Environmental Sciences,Chinese Academy of Sciences,Beijing 100085;University of Chinese Academy of Sciences,Beijing 100049;School of Environmental and Municipal Engineering,Lanzhou Jiaotong University,Lanzhou 730070;Key Laboratory of Yellow River Water Environment in Gansu Province,Lanzhou 730070;Hebei Technology Innovation Center for Remote Sensing Identification of Environmental Change,Hebei Key Laboratory of Environmental Change and Ecological Construction,School of Geographical Sciences,Hebei Normal University,Shijiazhuang 050024;School of Water Conservancy and Environment,University of Jinan,Jinan 250024)

机构地区：[1]中国科学院生态环境研究中心,中国科学院饮用水科学与技术重点实验室,北京100085 [2]中国科学院大学,北京100049 [3]兰州交通大学环境与市政工程学院,兰州730070 [4]甘肃省黄河水环境重点实验室,兰州730070 [5]河北师范大学地理科学学院,河北省环境变化遥感识别技术创新中心,河北省环境演变与生态建设省级重点实验室,石家庄050024 [6]济南大学水利与环境学院,济南250024

出　　处：《环境科学学报》2024年第12期178-186,共9页Acta Scientiae Circumstantiae

基　　金：国家重点研发计划(No.2022YFC3203604);国家自然科学基金青年科学基金(No.51808541)。

摘　　要：生物还原固定是一种环境友好且低成本的铬(Cr)污染场地修复技术.天然有机质是一类含有醌类基团的复杂有机物,广泛存在于环境中,它与自然环境中铁(Fe)的氧化还原循环相耦合,对环境污染物迁移转化起到重要作用.本文研究了两种天然有机质(Suwannee River Natural Organic Matter(SRNOM)和Nordic Lake Natural Organic Matter(NLNOM))和水铁矿耦合作用对微生物还原固定Cr(Ⅵ)过程的影响.结果表明:SRNOM和NLNOM强化了Cr(Ⅵ)生物还原过程,强化系数分别达到1.69和1.34.在微生物还原水铁矿过程中,加入SRNOM和NLNOM后Fe(Ⅱ)的生成速率分别增加了11.6%和27.2%.在Cr(Ⅵ)和水铁矿还原过程中,天然有机质作为电子传递体,加速了微生物与电子受体之间的电子传递速率.当SRNOM和NLNOM分别与水铁矿共存时,对Cr(Ⅵ)生物还原过程产生了协同强化作用,强化系数分别达到2.79和3.34.这主要是由于天然有机质本身可促进Cr(Ⅵ)生物还原,同时其促进水铁矿还原产生的Fe(Ⅱ)也可与Cr(Ⅵ)反应,进一步加速Cr(Ⅵ)的还原固定.结果表明,自然界中广泛存在的天然有机质与水铁矿可协同加速微生物还原固定Cr(Ⅵ)的过程.研究结果为深入了解自然界中Cr的迁移转化过程提供了理论依据,并为实际Cr污染场地修复提供了新的思路.Jinan;Bioreduction and immobilization is an environmentally friendly and low-cost remediation technology for chromium(Cr)contaminated sites.Natural organic matter(NOM)is a complex organic substance containing quinone groups,widely present in the environment.Coupled with the redox cycle of iron(Fe)in the natural environment,NOM plays a crucial role in the migration and transformation of environmental pollutants.This study investigated the influence of two types of NOM(Suwannee River Natural Organic Matter,SRNOM,and Nordic Lake Natural Organic Matter,NLNOM)and their coupled effect with ferrihydrite on the microbial reduction and immobilization of Cr(Ⅵ).The results showed that SRNOM and NLNOM enhanced the bioreduction process of Cr(Ⅵ),with enhancement factors of 1.69 and 1.34,respectively.During the microbial reduction of ferrihydrite,the addition of SRNOM and NLNOM increased the formation rate of Fe(Ⅱ)by 11.6%and 27.2%,respectively.In the bioreduction process of Cr(Ⅵ)and ferrihydrite,NOM acted as an electron shuttle,accelerating the electron transfer rate between microorganisms and electron acceptors.When SRNOM and NLNOM were combined with ferrihydrite,they exhibited a synergistic enhancement effect on the bioreduction of Cr(Ⅵ),with enhancement factors reaching 2.79 and 3.34,respectively.This is mainly attributed to the fact that NOM itself can promote the bioreduction of Cr(Ⅵ),and the Fe(Ⅱ)produced by its promotion of ferrihydrite reduction can also react with Cr(Ⅵ),further accelerating the reduction and immobilization of Cr(Ⅵ).The results demonstrate that the widely present NOM and ferrihydrite in nature can synergistically accelerate the microbial reduction and immobilization of Cr(Ⅵ).The findings provide a theoretical basis for understanding the migration and transformation processes of Cr in nature and offer new insights for the remediation of Cr-contaminated sites.

关 键 词：铬 生物还原 天然有机质 水铁矿 协同强化 

分 类 号：X505[环境科学与工程—环境工程] X131