Removal of arsenic from drinking water by batch and continuous electrocoagulation processes using hybrid Al-Fe plate electrodes



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/m2, 150 µg/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 €/m3). 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 µg/L in the CEC process was achieved at 3 min for 0.05 L/min (5.9 µg/L), 8 min for 0.10 L/min (6.3 µg/L), and 20 min for 0.20 L/min (8.4 µg/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 µg/L were determined as 0.0095–0.025 kg/m3 and 0.009–0.060 €/m3. © 2013 American Institute of Chemical Engineers Environ Prog, 33: 131–140, 2014