Insights on Pb(ii) retention and immobilization by ferrihydrite in the presence of Al(iii) and oxalic acid. Issue 6 (10th May 2022)

• Record Type: Journal Article
• Authors: Yu, Peijing; Ariya, Parisa A.; Fu, Fenglian; Tang, Bing
• Is Part Of: Environmental science. Volume 9:Issue 6(2022)
• Page Start: 2161
• Page End: 2171
• Publication Date: 2022-05-10
• Subjects: Environmental sciences -- Periodicals; Nanotechnology -- Periodicals; 620.505
• DOI: 10.1039/d2en00083k
• Languages: English
• ISSNs: 2051-8153

Abstract

Abstract : Al(iii ) and oxalic acid affect the migration of Pb(ii ) during ferrihydrite transformation under different pH values. Abstract : Lead (Pb) is harmful to humans and the natural environment. Unstable ferrihydrite with Pb(ii ) (Fh-Pb) transforms to more stable iron oxides over time. Al(iii ) and oxalic acid exist widely in nature, affecting the transformation of Fh-Pb. We herein studied the impacts of Al(iii ) and oxalic acid on the redistribution of Pb(ii ) during the Al-containing ferrihydrite–Pb(ii ) co-precipitate ageing process. Results indicated that Al(iii ) impeded the transformation of Fh-Pb, while oxalic acid counteracted the inhibition of Al(iii ) on the Fh-Pb interaction. The coexistence of Al(iii ) and oxalic acid hampered the release of Pb(ii ) to the environment under acidic conditions. Under neutral conditions, Al(iii ) promoted Pb(ii ) retention without oxalic acid, and oxalic acid caused the release of Pb(ii ) to the environment. Under alkaline conditions, Al(iii ) assisted Pb(ii ) intrusion into the iron oxides in the presence or absence of oxalic acid. This study contributes significantly to understanding the effect of selected impurities and organic substances on the Pb(ii ) behaviour at various pH values in environmental systems, namely in geological radioactive disposal sites, wastewater ponds and mine sites.