TY - JOUR
T1 - Glycine-mediated heavy metal leaching and calcium retention from municipal solid waste incineration fly ash
T2 - A mechanistic study
AU - Li, Hailong
AU - Xu, Zhenyao
AU - Peng, Yaqi
AU - Xu, Mengxia
AU - Li, Hongxian
AU - Han, Zhongkang
AU - Lu, Shengyong
AU - Yan, Jianhua
N1 - Publisher Copyright:
© 2025 Elsevier Ltd
PY - 2025/7
Y1 - 2025/7
N2 - Traditional acid washing with agents like hydrochloric and acetic acid can effectively extract heavy metals from municipal solid waste incineration fly ash (referred to as “fly ash”) but also dissolve calcium, complicating subsequent resource utilization. This study proposes the use of glycine as a green leaching agent to effectively extract heavy metals while retaining calcium under mild conditions. A systematic analysis was conducted to assess the effects of glycine concentration and temperature on the efficacy of heavy metal leaching. The concept of relative leaching efficiency was employed to evaluate the performance of various additives on fly ash. Notably, glycine improved the leaching efficiencies for heavy metals such as Cd, Cu, Ni, and Zn, bound to Fe-Mn oxides, by 79.8 %, 74.3 %, 36.3 %, and 64.5 %, respectively, compared to HCl-treated samples. Characterization studies and density functional theory (DFT) calculations demonstrate that glycine serves as proton donor and a chelating agent during the leaching process, enhancing the extraction of cationic heavy metals while minimizing calcium loss. These findings underscore glycine's potential role in advancing strategies for fly ash resource utilization.
AB - Traditional acid washing with agents like hydrochloric and acetic acid can effectively extract heavy metals from municipal solid waste incineration fly ash (referred to as “fly ash”) but also dissolve calcium, complicating subsequent resource utilization. This study proposes the use of glycine as a green leaching agent to effectively extract heavy metals while retaining calcium under mild conditions. A systematic analysis was conducted to assess the effects of glycine concentration and temperature on the efficacy of heavy metal leaching. The concept of relative leaching efficiency was employed to evaluate the performance of various additives on fly ash. Notably, glycine improved the leaching efficiencies for heavy metals such as Cd, Cu, Ni, and Zn, bound to Fe-Mn oxides, by 79.8 %, 74.3 %, 36.3 %, and 64.5 %, respectively, compared to HCl-treated samples. Characterization studies and density functional theory (DFT) calculations demonstrate that glycine serves as proton donor and a chelating agent during the leaching process, enhancing the extraction of cationic heavy metals while minimizing calcium loss. These findings underscore glycine's potential role in advancing strategies for fly ash resource utilization.
KW - Calcium matrix
KW - Density functional theory
KW - Glycine
KW - Heavy metals leaching
UR - http://www.scopus.com/inward/record.url?scp=105005604083&partnerID=8YFLogxK
U2 - 10.1016/j.jenvman.2025.125928
DO - 10.1016/j.jenvman.2025.125928
M3 - Article
AN - SCOPUS:105005604083
SN - 0301-4797
VL - 387
JO - Journal of Environmental Management
JF - Journal of Environmental Management
M1 - 125928
ER -