title: Electrokinetic removal of Cu and Zn in anaerobic digestate: interrelation between metal speciation and electrokinetic treatments.
abstract: In recent years, a potential controversy has arisen that whether the metal speciation in solid matrix determined its electrokinetic (EK) removal efficiency or by contrast. In present study, Cu and Zn in anaerobic digestate were selected as candidates to investigate the relation between the species of metal and EK treatment. The obtained results show that the removal efficiency for each fraction decreased in the order as follows: exchangeable ≥ bound to carbonates > bound to Fe-Mn oxides>bound to organic matters >> residual. For both Cu and Zn, their total removal performance was dependent on their dominant fraction in the digestate. A constant pH maintenance around the digestate via circulation of acid electrolyte is an optional operation because a strong acid atmosphere (pH < 2) around the digestate can be formed automatically as EK time elapses. Despite that many reactions occurred during EK process, the species distribution of Cu and Zn in the digestate determined their total EK removal efficiency essentially.
authors.affiliation: Biogas Institute of Ministry of Agriculture, 13 4th Section Renmin South Road, Chengdu, Sichuan Province 610041, China; Key Laboratory of Development and Application of Rural Renewable Energy, Ministry of Agriculture, 13 4th Section Renmin South Road, Chengdu, Sichuan Province 610041, China.
authors.forename: Neng-min
authors.initials: NM
authors.lastname: Zhu
authors.affiliation: Key Laboratory of Solid Waste Treatment and Resource Recycle (SWUST), Ministry of Education, Southwest University of Science and Technology, 59 Qinglong Road, Mianyang 621010, China.
authors.forename: Mengjun
authors.initials: M
authors.lastname: Chen
authors.affiliation: Biogas Institute of Ministry of Agriculture, 13 4th Section Renmin South Road, Chengdu, Sichuan Province 610041, China; Key Laboratory of Development and Application of Rural Renewable Energy, Ministry of Agriculture, 13 4th Section Renmin South Road, Chengdu, Sichuan Province 610041, China.
authors.forename: Xu-jing
authors.initials: XJ
authors.lastname: Guo
authors.affiliation: Biogas Institute of Ministry of Agriculture, 13 4th Section Renmin South Road, Chengdu, Sichuan Province 610041, China; Key Laboratory of Development and Application of Rural Renewable Energy, Ministry of Agriculture, 13 4th Section Renmin South Road, Chengdu, Sichuan Province 610041, China.
authors.forename: Guo-quan
authors.initials: GQ
authors.lastname: Hu
authors.affiliation: Biogas Institute of Ministry of Agriculture, 13 4th Section Renmin South Road, Chengdu, Sichuan Province 610041, China; Key Laboratory of Development and Application of Rural Renewable Energy, Ministry of Agriculture, 13 4th Section Renmin South Road, Chengdu, Sichuan Province 610041, China.
authors.lastname: Yu-Deng
mesh_terms: D000693:Anaerobiosis; D000818:Animals; D002254:Carbonates / Q000737:chemistry; D003300:Copper / Q000737:chemistry*; D004563:Electrochemistry; D004566:Electrodes; D004867:Equipment Design; D006863:Hydrogen-Ion Concentration; D007501:Iron / Q000737:chemistry; D007700:Kinetics; D008345:Manganese / Q000737:chemistry; D019216:Metals, Heavy / Q000737:chemistry*; D010100:Oxygen / Q000737:chemistry; D012722:Sewage; D013552:Swine; D014873:Water Pollutants / Q000737:chemistry; D015032:Zinc / Q000737:chemistry*
chemical_list: D002254:Carbonates; D019216:Metals, Heavy; D012722:Sewage; D014873:Water Pollutants; D008345:Manganese; D003300:Copper; D007501:Iron; D015032:Zinc; D010100:Oxygen
keywords: Anaerobic digestate; Electrokinetic process; Heavy metals; Metal speciation