Effect of enhanced biogeochemical transformation of tetrachloroethylene by EVO–FeSO4 and its transport characteristics in aquifers

Abstract

In situ biogeochemical transformation (ISBGT) of chlorinated solvents has received much attention in recent years due to the decreased toxicity of intermediates. However, under natural conditions, it can only occur in contaminated areas rich in iron and sulfur sources and takes several years, thus adding amendments to enhance this process is an alternative. Here, experiments were conducted to determine the potential of emulsified vegetable oil (EVO)–FeSO₄ to promote the biogeochemical transformation of tetrachloroethylene. Results of column studies show that EVO–FeSO₄ has good migration performance in various media. Within 95 days, 100 mg L⁻¹ tetrachloroethylene was effectively removed, and trichloroethylene accumulation was significantly lower than that of biofortification. Finally, the medium was characterized and the optimum proportion of EVO and FeSO₄ was determined. Overall, this work confirmed the feasibility of EVO–FeSO₄ as a biogeochemical transformation enhancement reagent in contaminated aquifers and provide a basis for the application.