Enhancement the stability of the titanium/graphite photo-electrode in varying voltages for treatment of textile wastewater using reactive blue 19 as the model contaminant

This study aims to investigate the treatment of textile wastewater containing reactive blue 19 dye (RB19) by graphite-based photo-electrode (GBPE). Simultaneously with the electrocatalytic process, irradiation by UVA lamp was also performed. The residual dye concentration was measured by UV/Visible spectrophotometry at wavelength of 590 nm. The structural characteristics of the composite was analyzed using FESEM, FTIR, and XRD. According to the results, the highest removal efficiency was obtained under acidic pH conditions. The maximum removal of 100% of the dye was observed in the different voltages and times (1.5 V/cm at 120 min, 2 V/cm at 100 min and 2.5 and 3 V/cm at 80 min). Under optimal conditions of pH = 5, RB19 concentration 100 mg/L, time of 20 min, voltage 0. 5 V/cm, and UVA irradiation of 12 W, the removal efficiency was 33%. The loose of graphite electrode (GE) duo to corrosion was 1 g in UVA/TiO₂/EK which increased to 2.1 g in UVA/EK. The removal efficiency of RB19 after six runs decreased to 63%. Results of oxygen consumption rate inhibition (OCRI) test showed the highest decrease in toxicity for the EK process, while the UVA/TNPs/EK process exhibited the least reduction. The real wastewater treatment using electrolysis with GBPE showed the removal efficiencies of 32% and 40% for COD and TOC, respectively. The findings provide valuable insights into the efficiency of titanium/graphite photo-electrodes for textile wastewater treatment applications.