摘要
该研究从土壤中分离纯化得到1株耐镉性较好的细菌,通过对其生长特性、菌液Cd2+浓度变化及矿化产物特性分析,探究菌株对Cd2+的钝化行为及去除效果。结果表明,实验菌株初步被确定为硫酸盐还原菌(SRB)。SRB的去除效果随Cd2+浓度增大而降低。在其生长过程中液相pH不断升高,有利于诱导合成硫化镉。当Cd2+初始浓度为10 mg/L时,菌株对Cd2+的去除率达到95%。此时,SRB的适应性最强且钝化效果稳定。Cd2+初始浓度为40 mg/L时,菌株对Cd2+的去除率为75%。通过SEM-EDS和XRD表征确定其矿化产物为硫化镉。研究显示,SRB可以有效钝化游离态的重金属离子,有望为突发性、高浓度重金属污染地区的原位治理提供新的思路。
In this study,a Cd-tolerant bacterium was isolated from soil.The passivation behaviors and removal effect of bacteria on Cd2+were investigated by analyzing its growth characteristics,Cd2+concentration changes and mineralization products.The results showed that the experimental strain was initially identified as sulfate-reducing bacteria(SRB).The removal efficiency of SRB decreased with the increase of Cd2+concentration.When the initial concentration of Cd2+was 10 mg/L,the removal rate of Cd2+was 95%.At this point,SRB has the strongest adaptability and stable passivation effect.When the initial concentration of Cd2+was 40 mg/L,the removal rate of Cd2+was 75%.The mineralized product was determined to be cadmium sulfide by SEM-EDS and XRD characterization.The experimental study showed that SRB could effectively free passivation of heavy metal ions,which can provide a new method for in situ treatment of sudden,high concentration of heavy metal pollution in the area.
作者
董净
代群威
赵玉连
邓远明
黄雪菊
韩林宝
罗红霞
DONG Jing;DAI Qunwei;ZHAO Yulian;DENG Yuanming;HUANG Xueju;HAN Linbao;LUO Hongxia(School of Environment and Resource,Southwest University of Science and Technology,Mianyang 621010,China;College of Life Science and Engineering,Southwest University of Science and Technology,Mianyang 621010,China;Soil and Groundwater Research Institute,Sichuan Academy of Environmental Sciences,Chengdu 610041,China)
出处
《环境科学与技术》
CAS
CSCD
北大核心
2019年第5期34-40,共7页
Environmental Science & Technology
基金
国家自然科学基金(41130746)
关键词
硫酸盐还原菌
土壤重金属污染
Cd2+钝化
生物矿化
土壤修复
sulfate-reducing bacteria
soil heavy metals pollution
passivation of Cd2+
biomineralization
soil remediation
