Effect of ethanol on persulfate oxidation of BTEX in groundwater

Persulfate has been widely used for in situ chemical oxidation remediation of organic pollutants in soil and groundwater. With the promotion of ethanol gasoline, the problem of groundwater pollution caused by ethanol gasoline has become more and more serious. Therefore, it is necessary to remove such pollutants. Previous studies on ethanol gasoline mostly focused on natural restoration technology. In order to further explore the more effective technical means to remove ethanol gasoline from groundwater and gain insight into the potential risks of ethanol degradation of BTEX, it is needed to study the use of new repair methods. In this paper, a batch experiment is conducted to explore the remediation effect of persulfate oxidation on ethanol-contaminated groundwater and the influences of Fe2+ activation and persulfate addition method on the removal of aromatics (BTEX) and ethanol. The results indicate that persulfate activated by Fe2+ effectively removes BTEX from groundwater, but inhibits biodegradation of BTEX. When ethanol is present, the persulfate preferentially oxidizes BTEX, and its removal rate is significantly higher than that of ethanol, which is exactly the opposite of pure biodegradation. If the total amount of persulfate addition is constant, batch addition is more conducive to the removal of BTEX, but has no obvious promotion effect on ethanol removal. This study provides an important reference for the application of persulfate ISCO in the remediation of the contaminated groundwater by ethanol gasoline.