负载型颗粒活性炭催化过硫酸钠氧化降解橙黄G

通过在颗粒活性炭(GAC)上负载氧化铁,并以此作为催化剂(Fe/GAC)在常温常压下催化过硫酸钠(PS)产生硫酸根自由基降解偶氮染料橙黄G。研究了体系pH、氧化剂浓度、催化剂浓度对橙黄G去除率的影响,并且对催化剂的重复使用性能进行了测试。结果表明,在Fe/GAC/PS体系中,[OG]0=0.2 mmol/L,[GAC]=1 g/L,[PS]0=2 mmol/L,降解2 h后OG去除率为99%,且有较高的矿化率;随着氧化剂浓度和催化剂浓度的增加,OG的去除效率提高;催化剂有较好的重复使用性。利用扫描电镜(SEM)对催化剂进行了表征,可以看出在活性炭上成功负载氧化铁。利用化学分子探针竞争实验鉴定催化反应中的活性物种SO4-·和OH·。

Degradation of orange G catalyzed by Fe/GAC in the presence of persulfate

This laboratory study was designed to investigate the degradation performance of modified GAC by Fe(NO3)3 in the presence of persulfate at ambient temperature and pressure.The effects of initial pH, initial concentration of persulfate, catalyst dosage on the reaction were discussed, in addition, the catalytic properties of reused catalyst were investigated.The results demonstrated that the OG removal efficiency was 99% under the optimum condition ([PS]0=2 mmol/L, [OG]0=0.2 mmol/L and [GAC]0=1.0 g/L) in 2 h reaction time.The degradation efficiency of OG enhanced as the catalyst and PS increased.The ferric oxide was found on the surface of GAC successfully by scanning electron microscopy(SEM).The catalytic reaction mechanism of producing sulfate radical and hydroxyl radical in Fe/GAC/PS system was discussed by molecular probes (methanol and nitrobenzene) methods.