Evaluation of Electrochemical Process on Polyphosphate Removal from the Aqueous Solution

Aims The effect of electrochemical process on polyphosphate alone has not been yet investigated. The aim of this study was to study polyphosphate removal from synthetic wastewater by electrochemical process. Materials & Methods This research was carried out experimentally on 50 samples of synthetic wastewater. In each run 2000ml of SW took place in a batch. A constant 600mA direct current was applied on the batch content through steel electrodes. First synthetic wastewater samples with initial concentrations in the range of 2-16mgL-1-P were examined and one sample was taken every 2min during 12min. Then samples in the range of 2 to 32mgL-1-P were tested and one sample was taken every 10min during 1 hour. Residual phosphorous in taken samples was measured according to Standard Methods book. Findings The removal efficiency was 85-99.85%. Residual phosphorous concentration was reduced below 1mgL-1-P (Iranian standard) in 1.15mA/cm2 DC. The needed reaction time was 10min. for 2-16mgL-1-P initial concentration whereas at higher concentrations it was 30min. Also, the reaction was first order with respect to the residual phosphorous concentration. Conclusion This process is efficient for removal of the over 99% of poly phosphate from the wastewater and able to reduce the residual phosphorous in effluent to less than Iranian standard limits for reuse (≤1mgL-1)