A fixed bed electrochemical reactor comprising stainless steel cathode/granular activated carbon (GAC) bed//Carbon anode//GAC bed//stainless steel cathode configuration was fabricated and tested for degradation of Reactive Blue 4 aqueous solutions (RB4). On the basis of measured concentrations of residual RB4 dye and total organic carbon (TOC), approximately 80–90% of RB4 dye was found to be degraded at 0.30–0.90 A and 13.4 ± 0.1 V in 6 h under recirculation batch mode of operation (flow rate, 1.8 Lh⁻¹). The dye removal due to adsorption on carbon was ∼9–10% under the same experimental conditions but excluding applied current. The apparent Faradic efficiency and electrical energy consumption were estimated to be 2.8% and 16.0 kWh kg⁻¹ RB4 at the optimum current and voltage (0.6 A, 13.3 V). Further, the adsorption of the dye on GAC bed, cyclic voltammetric response of RB4, SEM and FT-IR characterization of original and spent carbon and ion chromatographic analysis of inorganic intermediates were carried out to elucidate the mechanism of dye degradation. It appears that the dye degradation takes place by ready scission of SO₃H groups, and oxidation of mainframe chromophore (anthraquinone group). The chlorotriazine group resists to the electrooxidation and remains as the final reaction product.

制备了包括不锈钢阴极/颗粒活性炭（GAC）床//碳阳极// GAC床//不锈钢阴极构型的固定床电化学反应器，并测试了其对活性蓝4水溶液（RB4）的降解。根据测得的残留RB4染料和总有机碳（TOC）的浓度，在循环分批操作模式下，在6小时内在0.30-0.90 A和13.4±0.1 V的条件下，大约80-90％的RB4染料被降解。 （流速，1.8 Lh ^-1）。在相同的实验条件下，但不包括施加的电流，由于吸附在碳上而导致的染料去除率约为9-10％。表观法拉第效率和电能消耗估计为2.8％和16.0 kWh kg ^-1RB4处于最佳电流和电压（0.6 A，13.3 V）。此外，进行了染料在GAC床上的吸附，RB4的循环伏安响应，原始碳粉和废碳粉的SEM和FT-IR表征以及无机中间体的离子色谱分析，以阐明染料降解的机理。看来染料降解是通过立即切断SO ₃ H基团和大型发色团（蒽醌基团）的氧化而发生的。氯三嗪基团抗电氧化，并保留为最终反应产物。