氢气还原针铁矿紫外光协同催化双氧水氧化气体中甲醛  

Synergism of hydrogen peroxide and magnetite reduced from natural goethite in the presence of UV for oxidation of formaldehyde

作　　者：陈轶[1] 陈天虎[1] 陈冬[1] 邹雪华[1] 朱承驻[1] 吴亚东[1] 

机构地区：[1]合肥工业大学资源与环境工程学院,安徽合肥230009

出　　处：《岩石矿物学杂志》2013年第6期818-824,共7页Acta Petrologica et Mineralogica

基　　金：教育部博士点基金(20110111110003);国家支撑计划项目(2013BAC01B02)

摘　　要：甲醛作为一种致畸、致癌的高毒性有机污染物,对人体健康构成威胁,如何有效去除气体中的甲醛是关注的热点问题之一。采用粒径0.84～3.35 mm的天然针铁矿矿石于300℃氢还原转化为磁铁矿纳米材料,将纳米磁铁矿固定床非均相Fenton氧化反应器与紫外光催化双氧水氧化反应器串接,对比研究了双氧水、双氧水-紫外光、磁铁矿-双氧水、磁铁矿-双氧水-紫外光4种不同反应体系中双氧水投加量、甲醛初始浓度、载气流量对甲醛净化效率的影响。通过小型质谱仪对甲醛Fenton光催化氧化产物进行在线监测及TOC碳平衡分析,探讨甲醛净化的机理。结果显示制备的磁铁矿作为催化剂去除甲醛气体效果明显,在紫外光-10%双氧水-磁铁矿协同作用下,最高去除率可达98%,且在不同气速下对气体中不同浓度的甲醛都有很好的净化效果。研究结果表明,制备的磁铁矿纳米材料催化剂在去除甲醛气体过程中起着重要作用,经紫外光均相催化的双氧水协同作用可以在常温下很好地把气体中的甲醛氧化为CO2,是一种低成本的有机废气净化技术方法。How to remove the formaldehyde from gases effectively has long been one of the hot issues due to its high toxicity in carcinogenicity and teratogenicity.In this paper,nano-magnetite with particle sizes of 0.84～ 3.35 mm was prepared by reduction of goethite at 300℃ in hydrogen.An heterogeneous oxidation reactor filled with the prepared magnetite was connected with a reactor used to catalyze hydroge peroxide （H2O2） oxidation of formaldehyde.The effects of the amount of H2O2,the initial concentration of formaldehyde and the flow rate of carrier gas on the formaldehyde removal were investigated in four kinds of reaction system,namely H2O2,H2O2ultraviolet （UV）,magnetite-H2O2,and magnetite-H2O2-UV.The mechanism of Fenton photocatalytic oxidation of formaldehyde was evaluated by the combined application of a mass spectrometer total carbon analyzer.The results show that the formaldehyde removal rate in the Fenton photocatalytic oxidation can reach 98 ％ in the situation of UV-1O％ H2O2-magnetite.The stable result can be obtained in different gas velocity effects of different concentrations of formaldehyde.It is indicated that gaseous formaldehyde could be decomposed into CO2 owing to the synergies of nanoscale magnetite catalyst and homogeneous UV-catalyzed hydrogen peroxide at room temperature,which is a low-cost purification method for gaseous organic contaminants,at least for formaldehyde.

关 键 词：甲醛 针铁矿 光催化氧化 双氧水 铁氧化物 

分 类 号：P578.497[天文地球—矿物学] P579[天文地球—地质学]