Mineralization and Biodegradability Enhancement of Low Level pNitrophenol in Water Using Fentons Reagent

This study presents the use of dissolved organic carbon (DOC) and biodegradable dissolved organic carbon (BDOC) to indicate the degree of mineralization and biodegradability (BDOC/DOC) change of a dilute pnitrophenol aqueous solution (initial DOC of 8.5 MG/L) induced by Fentonʹs reagent. Fe^2+:H2O2:DOC ratios of 1:10:1, 10:10:1, and 10:100:1 and pH of 2, 3, and 4 were tested. Mineralization of p-nitrophenol of 5-35% was observed along with biodegradability increase. The best conditions for maximum mineralization were Fe^2+:H2O2:DOC of 10:10:1 and pH of 4 while the optimum conditions for highest biodegradability increase were Fe^2+:H2O2:DOC of 10:10:1 and pH of 3. Under the optimal conditions, the biodegradability was enhanced from 8 to 80%. More than 95% of total DOC removal and BDOC formation was observed in the first 10 min of the reaction. Results further indicated that Fe^2+:H2O2:DOC of 10:10:1 and pH of 4 were optimal for a combination of the maximum DOC elimination and biodegradability increase.