Abstract:

In view of the increasingly serious herbicide pollution, atrazine（ATZ）, as the target pollutant, was degraded by using ferrate to activate sulfite. The effects of sulfite concentration, ferrate concentration, ATZ concentration, pH and sulfite dosing ways on the removal of ATZ were investigated. The results show that under the conditions of pH 7, ferrate concentration of 100μmol/L, sulfite concentration of 400μmol/L, and ATZ concentration of 5μmol/L, 95% of ATZ can be removed within 10 seconds. The free radical quenching experiment was used to identify the active substances in the system. The results indicate that the main radicals in the ferrate-sulfite system are sulfate radicals (SO{}_{\mathrm{4}}^{·-}) and hydroxyl radicals (·OH), which accounts for 53% and 36%, respectively. By changing the sulfite dosing ways, the self-consumption of SO{}_{\mathrm{4}}^{·-} was reduced, and the degradation of ATZ in ferrate-sulfite system was improved. These experimental results are helpful for practical water treatment applications of ferrate-sulfite systems.

Key words: ferrate, sulfite, oxidation, activation, radical

摘要：

针对目前日益严峻的农药污染问题，本文以阿特拉津（ATZ）为目标污染物，利用高铁酸盐活化亚硫酸盐的方式对其进行降解。探究了亚硫酸盐浓度、高铁酸盐浓度、ATZ浓度、pH以及亚硫酸盐投加方式对ATZ去除率的影响。研究结果表明，在pH为7、高铁酸盐浓度为100μmol/L、亚硫酸盐浓度为400μmol/L、ATZ的浓度为5μmol/L的条件下，10s时间内可以去除95%的ATZ。利用自由基淬灭实验对体系中的活性物质进行鉴定，结果表明，高铁酸盐-亚硫酸盐体系中起主要作用的是硫酸根自由基（SO{}_{\mathrm{4}}^{·-}），其对ATZ降解的贡献约占53%；其次是羟基自由基（·OH），约占36%。通过改变亚硫酸盐投加方式，减少了SO{}_{\mathrm{4}}^{·-}的自我消耗，提高了高铁酸盐-亚硫酸盐降解ATZ的效率。这些实验结果有助于高铁酸盐-亚硫酸盐体系的实际水处理应用。

关键词: 高铁酸盐, 亚硫酸盐, 氧化, 活化, 自由基