Transformation of Dissolved Organic Phosphorus to Phosphate Using UV/H2O2

Phosphorus (P) driven eutrophication remains a problem in waterways worldwide. High P levels can significantly alter ecosystems, changing species composition and diversity. Most current P treatment technologies cannot adequately remove recalcitrant forms of P from the water column. As a result, this study evaluated the UV/H2O2 advanced oxidation process (AOP) for the photodegradation of recalcitrant-P in natural waters to biologically available phosphate, which is analogous to soluble reactive P (SRP). In turn, SRP can be removed using available P treatment technologies. The UV/H2O2 AOP was tested in synthetic waters and natural water from the Florida Everglades. Results showed that the photodegradation of recalcitrant P to SRP is possible using UV fluences of at least 5.1 J/cm(2) and H2O2 doses of at least 50 mg H2O2/L. The UV/H2O2 AOP was able to consistently convert recalcitrant-P to SRP in synthetic waters. However, the complex chemistry of Everglades water made consistent conversion of recalcitrant-P to SRP hard to achieve. An increase in the efficiency of UV lights is needed to make the UV/H2O2 AOP economically feasible for conversion of recalcitrant-P to SRP in natural waters. (C) 2015 American Institute of Chemical Engineers Environ Prog, 35: 680-691, 2016