Effects and mechanisms of mineral amendment on thallium mobility in highly contaminated soils

• Published in: Journal of environmental management Vol. 262; p. 110251
• Main Authors: Liu, Juan, Ren, Jiamin, Zhou, Yuchen, Tsang, Daniel C.W., Lin, Jingfen, Yuan, Wenhuan, Wang, Jin, Yin, Meiling, Wu, Yang, Xiao, Tangfu, Chen, Yongheng
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 15.05.2020
• Subjects: China; Environmental Monitoring; Green/sustainable remediation; In-situ stabilization; Metal fractionation; Minerals; Potentially toxic elements; Soil; Soil amendment; Soil Pollutants; Thallium; China; Green/sustainable remediation; In-situ stabilization; Metal fractionation; Soil amendment; Potentially toxic elements
• ISSN: 0301-4797; 1095-8630
• DOI: 10.1016/j.jenvman.2020.110251

Thallium (Tl) is an extremely toxic element, whose toxicity is even higher than mercury, arsenic, and cadmium. It is of great significance to hinder the migration and transfer of Tl from soils to the plants. A synthetic mineral amendment (SMA), mainly composed of different silicates, was evaluated for its effects on the transformation and retention of Tl in two typical highly Tl-contaminated soils from Southwest China. The results indicated that the addition of mineral amendment increased the soil of the pH by 0.46–2.13 units and distinctly reduced the content of active thallium in the soils. The extent of Tl reduction was related to the morphological characteristics of the original soil In particular, the application of the mineral amendment transformed 25.8–52.5% of the active Tl fractions in the soils to the residual fraction at 60 d. Adding mineral amendment to the soils can provide conditions to facilitate Tl to enter the silicate crystal lattice. The results of XPS evidenced that the proportion of Tl(I) in the soil was greatly reduced after adding the mineral amendment. •A synthetic mineral amendment (SMA) was applied to restore thallium (Tl) polluted soil.•SMA transformed 25.8–52.5% of the active Tl fractions to the residual fraction.•The proportion of Tl(I) in soil was greatly decreased after SMA was applied.•SMA immobilization method provides practical significance in Tl hazard mitigation.