Arsenic Speciation and Extraction and the Significance of Biodegradable Acid on Arsenic Removal—An Approach for Remediation of Arsenic-Contaminated Soil

International Journal of Environmental Research and Public Health

Yasuhito Osanai¹  Thinh Nguyen Van¹  Kiyoshi Kurosawa²  Hai Do Nguyen³ 

[1] Graduate School of Integrated Sciences for Global Society, Kyushu University, Fukuoka 819-0395, Japan;Institute of Tropical Agriculture, Kyushu University, Fukuoka 812-8581, Japan;Soil Science Department, Faculty of Land Management, Vietnam National University of Agriculture, Hanoi 100-000, Vietnam;

关键词: arsenic contamination;    sequential extraction;    biodegradable organic acid;    soil washing;    soil remediation;   

DOI  :  10.3390/ijerph14090990

来源: DOAJ

【 摘 要 】

A series of arsenic remediation tests were conducted using a washing method with biodegradable organic acids, including oxalic, citric and ascorbic acids. Approximately 80% of the arsenic in one sample was removed under the effect of the ascorbic and oxalic acid combination, which was roughly twice higher than the effectiveness of the ascorbic and citric acid combination under the same conditions. The soils treated using biodegradable acids had low remaining concentrations of arsenic that are primarily contained in the crystalline iron oxides and organic matter fractions. The close correlation between extracted arsenic and extracted iron/aluminum suggested that arsenic was removed via the dissolution of Fe/Al oxides in soils. The fractionation of arsenic in four contaminated soils was investigated using a modified sequential extraction method. Regarding fractionation, we found that most of the soil contained high proportions of arsenic (As) in exchangeable fractions with phosphorus, amorphous oxides, and crystalline iron oxides, while a small amount of the arsenic fraction was organic matter-bound. This study indicated that biodegradable organic acids can be considered as a means for arsenic-contaminated soil remediation.

【 授权许可】

Unknown