Persulfate is being used increasingly for in situ chemical oxidation of organic contaminants in groundwater. Laboratory experiments with aquifer sediments and pure minerals suggest that Fe and Mn convert persulfate to radical species over a time-scale of several weeks. To assess the reaction mechanism and improve the process, we studied the oxidation of benzene under conditions typical of groundwater treatment systems. Sulfate radicals produced by reactions on metal oxides initiated the oxidation of benzene through a complex chain reaction involving the formation of intermediate organic radicals. The organic radicals reacted with oxygen to produce species that initiated further decomposition of persulfate, as evidenced by a decrease in the reaction rate in the absence of oxygen. Analysis of product yields indicated that the expected oxidation product, phenol, only accounted for approximately half of the benzene loss with ring cleavage products accounting for much of the remainder of the benzene loss.

Oxidation of groundwater contaminants by metal oxide activation of persulfate: Radical chain mechanisms and product formation

245th National Meeting (2013)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.