Synchronous sequestration of cadmium and fulvic acid by secondary minerals from Fe(II)-catalyzed ferrihydrite transformation

Hu，Shiwen1,2; Zhen，Lirong3; Liu，Shuhu3; Liu，Chongxuan2; Shi，Zhenqing4; Li，Fangbai1; Liu，Tongxu1

2022-10-01

10.1016/j.gca.2022.08.006

GEOCHIMICA ET COSMOCHIMICA ACTA   Impact Factor & Quartile

0016-7037

1872-9533

As consequence of the dual demands for pollution control and carbon (C) fixation in soils, Fe(II)-catalyzed mineral transformation may be a promising method to simultaneously immobilize heavy metals or organic matter (OM), but the underlying mechanisms remain unclear. Here, the synchronous sequestration mechanism of cadmium (Cd) and fulvic acid (FA) during Fe(II)-catalyzed the transformation ferrihydrite with C/Fe molar ratio of 0.21 were examined. Mineral phase analysis revealed that increasing the Fe(II) concentration (1–5 mM) favored the transformation of lepidocrocite and goethite to magnetite, and ferrihydrite transformation rate increased with increasing Fe(II) concentration. Color overlays and line profiles of elements depicted that Cd was dominantly adsorbed on the lepidocrocite and goethite surfaces. A positive correlation between the quantity of nonextractable Cd and magnetite further indicated that Cd may be sequestered by magnetite. Meanwhile, FA molecules were adsorbed on goethite surfaces and magnetite aggregates, and incomplete structure of lepidocrocite provide spaces for immobilizing C. Newly formed iron (Fe) (oxyhydr)oxides may immobilize Cd through surface binding, structural substitution, and physical encapsulation. The OM bound to the newly formed Fe (oxyhydr)oxides was rich in aromatic and carboxyl functional groups, which was beneficial for binding Cd, whereas the presence of Cd promoted the generation of nano pore spaces or defects and consequently enhanced FA sequestration. Therefore, Cd immobilization and FA sequestration can be synchronously achieved during the phase transformation. The findings provide a profound insight into various nanoscale mechanisms accounting for the fate of Cd and FA coupled with mineral transformation. The findings also are very helpful for developing strategies for simultaneously immobilizing heavy metals and C in soils.

Cadmium Defects Ferrihydrite transformation Fulvic acid Organic matter Synchronous sequestration

SCI

English

NI Journal Papers

Others

Guangdong Basic and Applied Basic Research Foundation[2021A1515110904] ; China Post-doctoral Science Foundation[2021M701561] ; National Natu-ral Science Foundation of China["41830861","42125704"] ; Program for Guangdong Introducing Innovative and Entrepreneurial Teams[2017ZT07Z479]

Geochemistry & Geophysics

Geochemistry & Geophysics

WOS:000855258500002

PERGAMON-ELSEVIER SCIENCE LTD

GEOSCIENCES

2-s2.0-85136768120

Scopus

1.National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China,Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management,Institute of Eco-environmental and Soil Sciences,Guangdong Academy of Sciences,Guangzhou,510650,China
2.State Environmental Protection Key Laboratory of Integrated Surface Water-Groundwater Pollution Control,School of the Environmental Science and Engineering,Southern University of Science and Technology,Shenzhen,518055,China
3.Beijing Synchrotron Radiation Facility (BSRF),Institute of High Energy Physics,Chinese Academy of Sciences,Beijing,100049,China
4.The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters,Ministry of Education,School of Environment and Energy,South China University of Technology,Guangzhou,510006,China

Hu，Shiwen,Zhen，Lirong,Liu，Shuhu,et al. Synchronous sequestration of cadmium and fulvic acid by secondary minerals from Fe(II)-catalyzed ferrihydrite transformation[J]. GEOCHIMICA ET COSMOCHIMICA ACTA,2022,334:83-98.

Hu，Shiwen.,Zhen，Lirong.,Liu，Shuhu.,Liu，Chongxuan.,Shi，Zhenqing.,...&Liu，Tongxu.(2022).Synchronous sequestration of cadmium and fulvic acid by secondary minerals from Fe(II)-catalyzed ferrihydrite transformation.GEOCHIMICA ET COSMOCHIMICA ACTA,334,83-98.

Hu，Shiwen,et al."Synchronous sequestration of cadmium and fulvic acid by secondary minerals from Fe(II)-catalyzed ferrihydrite transformation".GEOCHIMICA ET COSMOCHIMICA ACTA 334(2022):83-98.