纳米磁铁矿催化降解邻苯二甲酸二丁酯

Oxidative Degradation of Dibutyl Phthalate by Nano-magnetite

文章通过共沉淀法合成了纳米磁铁矿,并利用XRD、TEM、VSM以及XAS对其形貌结构及磁性能进行表征,考察其在有氧条件下对邻苯二甲酸二丁酯(DBP)的催化活性。结果显示,向pH值为6.5的废水中加入过量磁性纳米材料,第1天在无氧条件下放置,第2天分2次共曝气30 min后,DBP的去除率达到64%,在反应期间磁铁矿被部分氧化成磁赤铁矿。通过液相色谱-质谱联用仪(UHPLC-MS/MS)鉴定了DBP的降解产物,推测了DBP可能的降解途径。同时,文章解释了该反应的反应机理,利用乙醇猝灭实验,提供了羟基自由基(HO·)参与了DBP的氧化降解反应的证据。该研究说明纳米磁铁矿是一种具有潜在优势的催化剂,能用于催化降解土壤和废水中的难降解有机污染物。

Nano-magnetite was synthesized through coprecipitation method,and the material was characterized by XRD, TEM,VSM and XAS.The oxidative capacity of nano-magnetite (Fe3O4)was investigated,and the composite was used as the heterogeneous Fenton-like catalyst for the removal of dibutyl phthalate (DBP).Results show that nearly 64% of DBP was eliminated after 30 min (two times)exposure to air bubbling in solution with pH value 6.5 in the presence of an excess of nano-magnetite.A partial oxidation of magnetite was also found to maghemite during the reaction.The intermediate products of DBP were identified by liquid chromatography-mass spectroscopy (UHPLC-MS/MS).At the same time,the mechanism of the reaction was explained.The evidence was provided that hydroxyl radicals (HO-)were involved in the oxidative degradation of DBP,as indicated by the quenching of the degradation reaction in the presence of ethanol.This study points out the promising potentialities of nano-magnetite for the treatment of soils and wastewater contaminated by organic pollutants.