Synergistic Release of Cd(II) and As(V) from Ternary Sorption Systems Containing Ferrihydrite Nanoparticles: The Role of Binary and Ternary Surface Complexes

Ming Lei; Miaomiao Jing; Dongning Wei; Zhuoqing Li; Yimin Zhou; Boqing Tie; Haojie Cui; Bingyu Li

doi:10.1016/j.chemosphere.2024.143515

Synergistic Release of Cd(II) and As(V) from Ternary Sorption Systems Containing Ferrihydrite Nanoparticles: The Role of Binary and Ternary Surface Complexes

Chemosphere. 2024 Oct 8:143515. doi: 10.1016/j.chemosphere.2024.143515. Online ahead of print.

Authors

Ming Lei¹, Miaomiao Jing¹, Dongning Wei², Zhuoqing Li¹, Yimin Zhou¹, Boqing Tie¹, Haojie Cui³, Bingyu Li⁴

Affiliations

¹ College of Environment and Ecology, Hunan Agricultural University, Changsha 410128, PR China; Hunan Engineering and Technology Research Center for Irrigation Water Purification, Changsha 410128, PR China.
² Institute of Nuclear Agriculture and Space Breeding, Hunan Academy of Agricultural Sciences, Changsha 410125, PR China. Electronic address: weidongning33@163.com.
³ College of Resources, Hunan Agricultural University, Changsha 410128, PR China.
⁴ College of Environment and Ecology, Hunan Agricultural University, Changsha 410128, PR China; Hunan Engineering and Technology Research Center for Irrigation Water Purification, Changsha 410128, PR China; College of Resources, Hunan Agricultural University, Changsha 410128, PR China; Institute of Agricultural Environment and Ecology, Hunan Academy of Agricultural Sciences, Changsha 410128, PR China. Electronic address: libingyu@hunau.edu.cn.

PMID: 39389370
DOI: 10.1016/j.chemosphere.2024.143515

Abstract

Cadmium (Cd) and arsenic (As) generally exhibit mutually beneficial co-sorption behavior on iron oxyhydroxides through multiple mechanisms, including surface precipitation, ternary surface complexes, and electrostatic interactions. However, the numerous factors that control the immobilization of Cd and As in turn complicated the processes and mechanisms involved in their co-desorption from iron minerals, which hindered the full understanding of their geochemical behaviors. Here, the simultaneous release of Cd(II) and As(V) from newly precipitated ferrihydrite nanoparticles by either Ca or P was investigated through kinetics and isothermal desorption experiments. We showed that the Cd(II) and As(V) present two-phase desorption processes (rapid desorption and slow desorption) in both binary (Fe-Cd or Fe-As alone) and ternary systems (Fe-Cd-As co-presence). Compared to their binary counterparts, Cd(II) and As(V) in the ternary systems are more prone to detachment from ferrihydrite. Further desorption of Cd(II) and As(V) at different co-presence scenarios (different initial concentrations) demonstrated mutual promotion behaviour towards their counterparts; the co-presence of Cd(II) facilitates the desorption of As(V), while the co-presence of As(V) also promotes the desorption of Cd(II). XPS and FTIR results demonstrated that either Ca or P showed minor effects on the binding environment of Cd and As. Further results from the in-situ ATR-FTIR experiment and second derivative peak fitting analysis indicate that the enhanced detachment of Cd(II) and As(V) from the ternary system may be due to the synergistic desorption of the ternary surface complexes and other surface complex species. Our results provide new insights into the prediction of the environmental behaviour of the coexistence of Cd(II) and As(V) in iron-rich geological settings. The potential environmental risks of iron-based remediation methods should be considered due to the enhanced bioavailability of Cd(II) and As(V) in co-presence circumstances.

Keywords: As; Cd; Desorption; Ferrihydrite; in-situ ATR-FTIR; ternary surface complexes.