New mechanism of FA in composted sludge inducing Cu fixation on Albite in open-pit mine soil  

作　　者：Jiapeng Wan Yifan Zeng Mei Wang Bin Dong Zuxin Xu 

机构地区：[1]State Key Laboratory of Pollution Control and Resource Reuse,College of Environmental Science and Engineering,Tongji University,Shanghai 200092,China [2]YANGTZE Eco-Environment Engineering Research Center,China Three Gorges Corporation,Beijing 100038,China [3]Shanghai Investigation Design&Research Institute Co.Ltd,Shanghai 200335,China

出　　处：《Journal of Environmental Sciences》2022年第6期142-150,共9页环境科学学报（英文版）

基　　金：supported by the Major Consulting Research Project of Chinese Academy of Engineering 2019-ZD-33;projects from the China Three Gorges Group Co.LTD(No.2020(W)-080,No.202003065)。

摘　　要：Fulvic acid(FA),typical organic matter derived from humification process in composted sludge,possesses the potential to remediate mine soils contaminated by heavy metals.To understand the cooper(Cu)immobilizing process in open-pit mine soil induced by FA,changes of Cu speciation in mixture of open-pit mine soil and composted sludge was tracked over 180 days.It was observed that the organic-bound and residual fraction of Cu increased dramatically with the corresponding decrease of Fe/Mn oxide-bound Cu in the first 60 days,then the organic-bound fraction decreased to about its initial proportion during 60-120 days,while residual fraction still increased,and the proportion of residual Cu accounted for over85%and became stable after 120 days.To reveal the mechanism of FA inducing Cu fixation on Albite which is the main phase of soil primary ore,two groups of Cu adsorption experiments with and without FA were designed.With the addition of FA,the adsorption capacity of Cu by Albite increased by 1.55 times and the content of residual Cu in Albite increased by7.7 times.It was found that the Cu absorbed in smaller Albite particle induced by FA formed a secondary mineral——Chrysocolla,causing increase of residual fraction of Cu.These results revealed the mechanism:FA was absorbed on the surface of Albite after complexing with Cu ions in the solution,and then it induced Cu into the interlayer and pore channels of Albite.The Cu in the Albite was immobilized by forming Chrysocolla finally.

关 键 词：Fulvic acid Composted sludge Heavy metal Open-pit mine MINERALIZATION 

分 类 号：X703[环境科学与工程—环境工程] X53[农业科学—肥料学] S141.4[农业科学—农业基础科学]