NOM组分对O3降解水中微污染有机物的影响

Effect of different natural organic matter fractions on the ozonation of micropollutants

摘要:

采用一系列不同截留分子量的超滤膜将提取的天然有机物(NOM)滤分为6种组分(NOM>10K、NOM5K-10K、NOM3K-5K、NOM1K-3K、NOM500-1K、NOM<500)组分,并研究了这6种NOM组分对臭氧(O3)氧化降解水中两种典型微污染有机物(双酚A和硝基苯)的影响.结果表明:对于与O3反应活性较高的有机物双酚A(BPA),NOM各组分的引入使得O3去除BPA效能有所下降;对于与O3反应活性较低的有机物硝基苯(NB),高分子量范围的NOM组分(NOM>10K、NOM5K-10K、NOM3K-5K、NOM1K-3K)的存在能强化O3的自由基链式分解反应,从而促进O3对硝基苯的去除.低质量浓度的NOM对O3氧化降解水中有机物的影响与NOM的特性(所含的官能团的类型和数量)以及目标有机物与O3的反应活性有关.

Abstract:

By fractioning natural organic matters (NOM) sourced from Songhua River with series of ultra membranes, the effect of each fraction on the degradation of BPA and NB by ozonation was investigated. It was found that the introduction of NOM fractions exept for NOM5K-10K and NOM3K-5K slightly decreased the removal efficiency of BPA which is highly reactive with ozone. On the contrary,for the refractory organic pollutant NB,NOM fractions,especially the fractions with high molecular weight (NOM>10K,NOM5K-10K,NOM3K-5K,and NOM1K-3K),promoted its degradation due to the enhancement of chain reaction which is accompanied by the formation of hydroxyl radical,and the extent of promotion depended on the types and amounts of functional groups contained in NOM fractions.