Ce-PbO2/C电极的制备及其去除水中酸性红B

采用电沉积法制备铈修饰的PbO2/C电极,通过SEM、XRD、XPS及循环伏安对PbO2/C、Ce-PbO2/C电极进行表征,结果表明,Ce-PbO2/C电极比PbO2/C颗粒细小,表面均匀致密,电化学氧化能力较强,修饰电极中Ce以CeO2的形态存在。以Ce-PbO2/C为工作电极,电解浓度为1 000 mg/L的高盐酸性红B模拟活性染料废水,考察了电压、pH、电解质浓度、极间距对脱色率、氨氮去除率及COD去除率的影响。确定适宜工艺条件为:初始酸性红B溶液浓度为1 000 mg/L,pH值为6,电压10 V,电解时间1 h,电极间距1.5 cm,该条件下脱色率、氨氮去除率和COD去除率分别为99.98%、97.23%和90.17%。通过UV-Vis及GC-MS初步分析了降解过程可能存在的中间产物及降解途径。

Preparation of Ce-PbO2/C and its application in removing Acid Red B from water

Graphite-lead dioxide electrodes doped with rare earth Ce were prepared by electrodeposition. Then the PbO₂/C electrode and Ce-PbO₂/C electrodes were characterized by SEM, XPS, XRD and cyclic voltammetry. The results showed that the Ce-PbO₂/C electrode surface is more dense and uniform and the crystal size is smaller, and its ability of catalytic oxidation is stronger than that of PbO₂/C. Ce in the modified electrode exists in CeO₂ morphology. The modified electrode was used as working electrode to treat high salinity simulative dyeing wastewater containing Acid Red B (1 000 mg/L),and the effects of different factors(voltage, pH, electrolyte concentration and electrode distance) on the removal efficiency of COD, colour and ammonia nitrogen were investigated. The optimum conditions are achieved as follows: the initial Acid Red B concentration of 1 000 mg/L, initial pH value of 6, the voltage of 10 V, electrolytic time of 1 h and electrode spacing of 1.5 cm. Under such conditions, the removal efficiency of colour, ammonia nitrogen and COD can reach up to 99.98%, 97.23% and 90.17%, respectively. The possible intermediates and degradation pathways of Acid Red B were monitored by UV-Vis spectra and GC-MS.