Adsorption of trace uranium on iron oxides: reconstruction of water chemistry from ancient lakes in Baikal catchment area.

2017 Fiscal Year Final Research Report

• Project/Area Number: 15K21019
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Petrology/Mineralogy/Economic geology; Geochemistry/Cosmochemistry
• Research Institution: Kanazawa University
• Principal Investigator: Fukushi Keisuke 金沢大学, 環日本海域環境研究センター, 准教授 (90444207)
• Project Period (FY): 2015-04-01 – 2018-03-31
• Keywords: ウラン / 鉄酸化物 / 吸着 / 表面錯体モデリング / フブスグル湖 / 水質 / pH

Outline of Final Research Achievements

Uranium concentrations in the sediments core obtained from Lake Hovsgol located in the catchment area of Baikal lake are varied with the core depth depending on the glacial - inter glacial periods. Because the uranium in the sediments was originated from the adsorption process of dissolved uranium onto iron oxide in the lake, the concentration of uranium in the sediments is expected to reflect the changes of water chemistry derived from the climatic change. In present study, the adsorption behavior of trace uranium was examined by adsorption experiments and modeled quantitatively. Results showed that the most important factor affecting the uranium concentrations in the sediments was pH. The adsorption modeling suggested that the pH of lake Hovsgol during the glacial periods, when the uranium concentrations in the sediments were extremely low, exceeded 9.5.

Free Research Field

地球化学