Sodium citrate enhancing electrodeposition of metallic arsenic from toxic trivalent arsenic and the mechanism understanding  

作　　者：Shuiping Zhong Tingyu Xu Hang Chen Ding Tang Wen Tan Wei Weng Yanru Shi 

机构地区：[1]Zijin School of Geology and Mining,Fuzhou University,Fuzhou 350108,China [2]Fujian Key Laboratory of Green Extraction and High-value Utilization of New Energy Metals,Fuzhou University,Fuzhou 350108,China [3]Zijin Mining Group Co.,Ltd.,Shanghang,Longyan 364200,China [4]Inner Mongolia Academy of Science and Technology,Hohhot 010010,China

出　　处：《Journal of Environmental Sciences》2025年第5期79-87,共9页环境科学学报(英文版)

基　　金：supported by the Industrial Technology Innovation Program of IMAST(No.2023JSYD03005);the National Key Basic Research and Development Program(No.2022YFC3900801);Fujian Province University-Industry Cooperation Research Program(No.2023H6007);the National Natural Science Foundation(No.52274349)and Fujian Province Natural Science Foundation(No.2023J05024).

摘　　要：Electrochemical conversion of hypertoxic trivalent arsenic to value-added metallic arsenic can not only contribute to pollution abatement,but also resources reutilization,therefore being widely explored.Electrochemical reduction of trivalent arsenic as a promising way is widely explored.However,the high efficiency conversion is retarded by the sluggish reduction kinetics of AsO33−and fierce evolution of side products of both H_(2)and toxic AsH_(3).Herein,by using the sodium citrate as the additive,the current efficiency for metal arsenic production is increased greatly from 60%to 91%,with the accompanied evolution of hypertoxic AsH_(3)being restrained from 0.15 Nm^(3)/t_(As)to 0.022 Nm^(3)/t_(As),promising a high-efficiency and green process.The electrochemical tests and electrode surface characterizations aswell as DFT calculations indicate that the added sodium citrate promotes both the diffusion of reactive AsO_(3)^(3−)towards the cathode and its subsequent adsorption on the Ti cathode,contributing to smoother reduction for generating metal arsenic,with the evolution of toxic AsH_(3)being hindered at the same time.The results can provide new insights for the highefficiency and greener conversion of hypertoxic trivalent arsenic to value-added metallic arsenic.

关 键 词：Toxic arsenic Electrochemical conversion Metallic arsenic Sodium citrate 

分 类 号：X171.5[环境科学与工程—环境科学]