Removal of nitrates from water by electrocoagulation using a cell with horizontally oriented Al serpentine tube anode

In this work, removal of nitrates by electrocoagulation in a batch electrochemical cell with horizontally oriented electrodes was studied, the anode was a horizontal Al serpentine tube whose inner surface can potentially act as a built-in cooler to control the cell temperature, a H-2 evolving Al plate cathode was placed beneath the anode at the cell bottom where the stirring action of H-2 bubbles improve the mixing conditions at the anode. The effect of operating parameters, such as initial NO3- concentration, initial pH of the solution, applied current density, and NaCl concentration on the removal efficiency was investigated. The electrical energy consumption of the cell was calculated at different operating parameters in order to optimize the operating conditions. The removal efficiency of the cell reached 100% after 100 min. A kinetic model for the process was proposed and verified by the experimental data. The merits of the present new cell which is self-stirred and contains a built-in heat transfer facility for temperature control were highlighted. Importance of the present work for agriculture drainage water and underground water remediation was pointed out. (C) 2019 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.