Improvement of electrocoagulation-electroflotation treatment of effluent by addition of Opuntia ficus indica pad juice

The aim of this study is the optimization of the effect of Opuntia ficus indica (OFI) pad juice on the electrocoagulation-electroflotation (EC-EF) water treatment process by response surface methodology (RSM). To estimate the efficiency of EC-EF technique assisted by Opuntia ficus indica pad juice, preliminary tests were conducted. The results obtained after RSM optimization for initial OFI pad juice volume, initial pH and initial conductivity were 0.016 mL/L, 82, and 3.04 mS/cm, respectively. Maximum predicted turbidity removal efficiency (TR %) under the optimized conditions was 87% +/- 0.8, this predicted value was close to the experimental value of 86.9% +/- 0.1. Compared to the conventional EC-EF (EC without OFI juice addition), which shows 71.9% of turbidity removal, the optimized cactus juice assisted EC-EF allows a turbidity removal enhancement of 15.1%. These results indicate suitability and validation of the employed model and the success of RSM in optimizing the EC-EF treatment conditions. (c) 2015 Elsevier B.V. All rights reserved.