铁元素作为环境广泛存在的元素,由于多价态特征而被广泛应用于催化氧化降解有机污染物,主要有零价铁和铁硫化物.以可溶性淀粉为碳源,FeSO4为铁源,通过碳热还原法合成多孔碳负载纳米零价铁和Fe0.96S的复合催化剂.利用X射线衍射(XRD)和扫描电子显微镜(SEM)探索铁元素的形态和形貌在碳热还原中的变化规律,研究其催化活化过硫酸钾(KPS)氧化降解水中染料刚果红(CR)的活性,分析影响活化KPS氧化降解CR效率的主要因素.结果表明,在碳化温度为800 ℃时,得到一种多孔碳负载纳米零价铁和Fe0.96S的复合催化剂.当CR初始质量浓度为500 mg/L、催化剂投加量为1 g/I时,30 min内CR的降解率可达约100%.CR降解过程会产生大量的小分子有机酸中间产物,导致反应过程溶液的pH逐渐降低至约3.因此,通过碳热还原法能获得多孔碳负载纳米零价铁和Fe0.96S的复合催化剂,可广泛应用于催化氧化去除水中有机污染物.
Iron,as one of the environment friendly and compatible elements,was widely used for catalytic oxidation of organic pollutants due to the variety valence.The catalytic species contained zero valent ion and Fe.In this work,a kind of porous char supported iron catalyst containing zero valent ion and Fe0.96S were prepared under carbothermal reduction process,in which the soluble starch and FeSO4 were conducted as carbon and iron precursors,respectively.The micromorphology and phase of the iron during carbothermal reduction process were characterized by XRD and SEM analysis.The catalytic activity of KPS activation for Congo red(CR)degradation was conducted in a batch experiments.The main factors determined the CR degradation efficiency was reported.A kind of porous char supported zero valent iron and Fe0.96 S was prepared under 800℃.The CR degradation efficiency attained to about 100%within 30 min in the presence of the catalyst with a dosage of 1 g/L and the initial CR concentration of 500 mg/L.Organic acid with small molecular was formed during the CR degradation,resulting in the decreased pH value to about 3.Therefore,the porous char supported zero valent iron and Fe0.96 S catalyst could be successfully prepared for activating KPS to degrade the CR with favorable activity,which is also promising in catalytic degradation of organic pollutants in wastewater.