Arsenite Removal from Groundwater by Novel Electrocoagulation Process: Statistical Modeling Gören A.Y. 1,2, Kobya M. 2,a, Demirbaş E.3, Şık E.3, Öncel M.S.2 1
Department of Environmental Engineering, İzmir Institute of Technology, İzmir-Turkey Department of Environmental Engineering, Gebze Technical University, Gebze-Turkey 3 Department of Chemistry, Gebze Technical University, Gebze-Turkey a. Corresponding author (
[email protected])
2
Removal of arsenite from groundwater by a novel electrocoagulation (EC) reactor using aluminum (Al) ball anodes was investigated. A Response Surface Method (RSM) based on the Box- Behnken Design (BBD) was used to investigate the effects of major operating variables e.g. initial pH (pHi: 5.5-8.5), operating time (tEC: 8-22 min), current (i: 0.1-0.5 A), size of Al anode ball (dp: 5-10 mm), initial As(III) concentration (C0: 100-1000 µg/L), air flow rate (Qair: 2-10 L/min) and column height of Al ball (h:2-8 cm). The Design-Expert program provided with responses such as removal efficiency, operating cost, energy consumption and effluent As(III) concentration for the electrocoagulation experiments. This study showed that statistical design methodology was an efficient approach in evaluating the optimum conditions for arsenite removal by a novel electrocoagulation. The maximum removal efficiency of As(III) and minimum operating cost at the optimized conditions (316.4 µg/L initial arsenite concentration, 0.25 A current, 5.5 pH, 22 min operating time, 6.6 mm size of Al anode ball, 2 cm column height of Al anode ball and 10 L/min air flow rate) were obtained as 99.3% and 0.464 $/m3, respectively. Keywords: Arsenite; Electrocoagulation; Al ball electrodes; RSM
