Removal of Arsenic from Drinking Water by Batch and Continuous Electrocoagulation Processes Using Hybrid Al-Fe Plate Electrodes

Abstract

Removals of arsenic from drinking water by electrocoagulation (EC) process using six different combinations of hybrid electrodes (Al-Fe), and Al-Al or Fe-Fe electrodes as all anodes and cathodes in a batch mode were evaluated. The removal process with monopolar series mode at optimum operating conditions (2.50 A/m(2), 150 mu g/L, and pH 7.0) indicated that Fe-Al-Al-Fe (anode-cathode-anode-cathode) hybrid plate electrode pairs were the most efficient choice in terms of arsenic removal efficiency (96% in 1 min) and operating cost (0.00202 Euro/m(3)). The arsenic removal from drinking water by continuous EC (CEC) process using Fe-Al-Al-Fe hybrid plate electrode pairs was also studied with respect to flow rates and initial arsenic concentrations. The effluent arsenic concentration of 10 mu g/L in the CEC process was achieved at 3 min for 0.05 L/min (5.9 mu g/L), 8 min for 0.10 L/min (6.3 mu g/L), and 20 min for 0.20 L/min (8.4 mu g/L), respectively. Amounts of the sludge and operating costs in the CEC process with respect to some experimental parameters such as operating time (3-20 min) and flow rate (0.05-0.20 L/min) at 150 mu g/L were determined as 0.0095-0.025 kg/m(3) and 0.009-0.060 Euro/m(3). (c) 2013 American Institute of Chemical Engineers Environ Prog, 33: 131-140, 2014