Uranium Fixation and Removal from Different Soil Types: Review

Uranium Fixation and Removal from Different Soil Types: Review

Environmental contamination caused by radionuclides, in particular by uranium and its decay products is a serious problem worldwide. The development of nuclear science and technology has led to increasing nuclear waste containing uranium being released and disposed in the environment. The objective of this paper is to develop a better understanding of factors affecting uranium fixation and removal from different soils with different soil characteristics. Soils contaminated with uranium at concentrations above regulatory limits pose an environmental and human health risk. Investigations about uranium content and fate in soils revealed several finding depending on soil factors, radionuclide source and nature, and existing vegetation in the area. In organic rich soils U seems to be more soluble and bioavailable. Data demonstrates the effectiveness of soil amendments (Hydroxyapatite, illite and zeolite) in reducing the mobility of U, which makes in-place immobilization an effective remediation alternative. In contrast to increase U solubility and leach-ability the maximum solubilization of U was observed with a combined soil acidification and citric acid addition, which may be necessary to maximize the phyto-extraction of U from soils with a pH >6.0.