Degradation of orange G by Fe2+/peroxydisulfate system with enhance of EGCG
BI Chen1,2, SHI Zhou1,2, ZHOU Shi-qing1,2, BU Ling-jun1,2
1. College of Civil Engineering, Hunan University, Changsha 410082, China;
2. Key Laboratory of Building Safety and Energy Efficiency, Ministry of Education, Hunan University, Changsha 410082, China
As a kind of green tea extract with reducing and chelating properties, epigallocatechin-3-gallate (EGCG) was introduced into Fe2+-activated peroxydisulfate (Fe2+/PDS) system to accelerate the transformation fromFe3+ to Fe2+ and enhance the degradation of orange G (OG). The effect of PDS dosage, initial concentration of OG, initial solution pH, Fe2+ dosage, EGCG dosage, and co-existing anions on degradation of OG was investigated. The results demonstrated that Fe2+, EGCG, PDS alone, and EGCG/PDS, Fe2+/EGCG system showed poor effectiveness on degradation of OG, while the involvement of EGCG into Fe2+/PDS system enhanced OG degradation significantly:from 30.89% to 83.71%. Besides, the degradation efficiency of OG increased along with the dosage of PDS and Fe2+, and decreased with the increase of initial OG concentration. An optimum dosage of EGCG was found at 40 μmol/L and the degradation efficiency of OG performed well in a wide pH range of 2.0~7.0. The degree of inhibition from strong to weak follows the order of PO43- > CO32-> Cl-. Furthermore, by adding two typical radical scavengers (TBA and MeOH), hydroxyl radical and sulfate radical were identified to be responsible for OG degradation and SO4·- made the predominant contribution.
毕晨, 施周, 周石庆, 卜令君. EGCG强化Fe2+/过硫酸盐体系降解金橙G的研究[J]. 中国环境科学, 2017, 37(10): 3722-3728.
BI Chen, SHI Zhou, ZHOU Shi-qing, BU Ling-jun. Degradation of orange G by Fe2+/peroxydisulfate system with enhance of EGCG. CHINA ENVIRONMENTAL SCIENCECE, 2017, 37(10): 3722-3728.
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