摘要
高锰酸钾(KMnO_(4))能有效降解水中有机污染物,但其氧化有机膦酸过程尚不明确。以氨基三亚甲基膦酸(NTMP)为例,采用自由基捕获实验和电子顺磁共振波谱(EPR)探究其在KMnO_(4)体系下降解的主要活性氧化物种,并考察了溶液化学性质(如pH、共存物质、实际水体等)对KMnO_(4)氧化降解NTMP的影响。结果表明:KMnO_(4)直接氧化是NTMP降解的主要途径,且NTMP降解受pH影响较大。当pH=5.0时,KMnO_(4)氧化NTMP的效果最佳,其中51.4%NTMP被氧化生成PO_(4)^(3-),远高于UV/H_(2)O_(2)和UV/过硫酸钾(PDS)体系。水体中共存物质(SO_(4)^(2-)、NO_(3)^(-)、HCO_(3)^(-)和腐植酸)对NTMP的降解抑制作用较小。此外,在实际水体中KMnO_(4)对NTMP仍有较高的降解效率,且其选择性优于自由基体系。研究结果可为实际废水中有机膦酸的高效去除提供重要参考。
Organic pollutants could be degraded by KMnO_(4),and the oxidation process of phosphonates by KMnO_(4) is still unclear.Herein,using nitrilotris(methylene phosphonic acid,NTMP)as a model pollutant,radical capture experiments and electron paramagnetic resonance(EPR)were used to explore the dominant active oxidizing species in KMnO_(4) system,and the effects of solution chemical properties(such as pH,coexisting substances,actual water body,etc.)on the degradation of NTMP by KMnO_(4) were investigated.The results showed that direct oxidation of KMnO_(4) was the dominant pathway for NTMP degradation,and its degradation was greatly influenced by pH value.The best oxidation performance of NTMP by KMnO_(4) was obtained at pH=5.0,and 51.4%of NTMP was oxidized into PO_(4)^(3-),much higher than that in UV/H_(2)O_(2) and UV/potassium persulfate(PDS)system.No obvious inhibition on the degradation of NTMP was observed in the presence of coexisting substances in water(i.e.,SO_(4)^(2-),NO_(3)^(-),HCO_(3)^(-),and humic acid).In addition,KMnO_(4) also showed a high degradation efficiency on NTMP in actual wastewater,and its selectivity was better than that of free radical systems.The results provide an important reference for the efficient removal of phosphonates from actual wastewater.
作者
彭娟娟
刘少敏
朱敬林
PENG Juanjuan;LIU Shaomin;ZHU Jinglin(School of Earth and Environment,Anhui University of Science and Technology,Huainan 232001,China)
出处
《环境工程》
CAS
CSCD
2024年第4期132-138,共7页
Environmental Engineering
基金
安徽省自然科学基金项目(2208085QB63)
安徽省高校科学研究项目(KJ2021A0442)
安徽理工大学高层次引进人才科研启动基金(2021yjrc04)。
关键词
高锰酸钾
氨基三亚甲基膦酸
直接氧化
正磷酸盐
potassium permanganate
nitrilotris(methylene phosphonic acid)
direct oxidation
orthophosphate
作者简介
第一作者:彭娟娟(1999-),女,硕士,主要从事水资源与水处理等方面的研究。3134461553@qq.com;通信作者:刘少敏(1972-),男,博士,教授,主要从事水资源与水处理等方面的研究。shmliu@aust.edu.cn。
