活性炭催化过硫酸钠降解金橙G动力学

采用颗粒活性炭(granular active carbon,GAC)催化过硫酸钠(sodium persulfate,PDS)产生具有强氧化性的硫酸根自由基,以偶氮染料金橙G(orange G,OG)为目标污染物,研究了其降解过程及动力学.结果表明,GAC/PDS体系能通过氧化作用有效地去除金橙G,其中氧化降解速率主要与PDS投量、GAC投加量、溶液的初始浓度及反应温度有关,升高温度和GAC投量可以显著地加快OG的降解.且在初始浓度为0.050～0.125 mmol·L-1、pH值为5.0、n(PDS)/n(OG)为10/1～160/1、GAC投量为0.1～1.6 g·L-1、温度为298～338 K的实验范围内,反应的氧化降解符合一级动力学模型且与实验值吻合良好.另外还对GAC重复使用之后的催化效果进行了初步考察.

Degradation Kinetics of Activated Carbon Catalyzed Persulfate Oxidation Orange G

The oxidation degradation of orange G(OG)in aqueous solutions by the activated carbon catalyzed peroxydisulfate(PDS) has been kinetically investigated. These processes are based on the generation of sulfate radicals, which are powerful oxidizing species found in nature. The results demonstrated that OG could be degraded by GAC/PDS reagent effectively. Moreover, the dosage of PDS and GAC, temperature and initial concentration of OG had an impact on OG oxidation, higher temperature and GAC dosage resulted in higher OG degrading rates. In addition, the empirical kinetic equation for OG oxidation by GAC/PDS combined system under the conditions of 0.050-0.125 mmol·L^-1 of OG, 5.0 of pH, 10/1-160/1 of n(PDS)/n(OG), 0.1-1.6 g·L^-1 of GAC, 298-338 K of temperature, could be reasonably represented by the first order kinetics, which was fitted very well with the experimental data. In addition, the catalytic properties of reused GAC have been investigated.