Electrochemical Degradation of Remazol Red BR and Novacron Blue C-D Dyes Using Diamond Electrode

In this paper, the treatment of dye solutions containing Remazol Red BR (RRB) and Novacron Blue C-D (NB) by anodic oxidation using boron-doped diamond (BDD) anodes has been investigated. Galvanostatic electrolyses of RRB and NB solutions have led to the complete decolourisation and chemical oxygen demand (COD) removal at different operating conditions (current density, pH and temperature). Energy requirements for removing colour during galvanostatic electrolyses of RRB and NB synthetic solutions depend mainly on operating conditions; for example for RRB, it passes from 3.30 kWh m(-3) at 20 mA cm(-2) to 4.28 kWh m(-3) at 60 mA cm(-2) (pH=1); 17.25 kWh m(-3) at 20 mA cm(-2) to 28.87 kWh m(-3) at 60 mA cm(-2) (pH=4.5); 13.50 kWh m(-3) at 20 mA cm(-2) to 37.80 kWh m(-3) at 60 mA cm(-2) (pH=8). Additionally, colour and COD removal rates were favoured when an increase on the temperature was attained, decreasing the energy consumption requirements. According to the experimental results obtained, the electrochemical oxidation process is suitable for depuration wastewaters containing these textile dyes, due to the electrocatalytic properties of BDD anode.