锌-铜混合纳米铁氧体催化活性对草酸镧分解动力学的影响（英文）

发布时间：2018-03-16 09:00

本文选题：混合铁氧体　切入点：尖晶石　出处：《Transactions of Nonferrous Metals Society of China》2016年03期 　论文类型：期刊论文

【摘要】：采用溶胶-凝胶法合成纳米结构锌-铜混合铁氧体。XRD分析表明,不同组分Zn_((1-x))Cu_xFe_2O_4(x=0.0,0.25,0.50,0.75)铁氧体为单相反尖晶石结构。随着铜含量的增加,晶粒尺寸增大。采用SEM表征样品的表面形貌,结果表明粒子为多孔结构。采用FT-IR和TEM分析所制备的样品。当x=0.75及催化剂为5%(摩尔分数)时,速率常数k值最高,这归因于高铜含量以及除Cu~(2+)-Cu~+和Fe~(3+)-Fe~(2+)外,由于电荷相互作用而产生的混合位Cu~(2+)-Fe~+和/或Cu~+-Fe~(2+)离子对。混合氧化物活性增加归因于通过新离子产生而增大的活性位置浓度。随着锌含量的增加,颗粒尺寸增大。铁氧体粉末催化活性的变化是因为催化活性组分价态的变化,这能氧化从草酸镧中释放的一氧化碳。
[Abstract]:XRD analysis of zinc-copper mixed ferrites prepared by sol-gel method showed that the different components ZnSZ, 1-xFe2O1-CuxFe2O4-CuxFe2O4, CuxFe2O4, CuxFe2O4, CuxFe2O4, CuxFe2O4, CuxFe2O4, CuxFe2O0, CuxFe2O0, CuxFe2O0, CuxFe2O4, CuxFe2O4, CuxFe2O0. 0. 0. 50% 0. 75) ferrite was synthesized by sol-gel method. The results show that the particles have porous structure. The samples prepared by FT-IR and TEM analysis have the highest rate constant k value when the catalyst is 5 (mole fraction), which is attributed to the high copper content and the addition of Cu~(2 ~ -Cu ~ and Fe~(3 ~ -Fe ~ (2). The Cu~(2 ~ -Fe ~ and / or Cu ~ -Fe ~ 2) ion pairs produced by the charge interaction increase the activity of the mixed oxides due to the increasing concentration of the active sites by the new ions. With the increase of the zinc content, the activity of the mixed oxides increases with the increase of the zinc content. The change of the catalytic activity of ferrite powder is due to the change of the valence state of the active component, which can oxidize the carbon monoxide released from lanthanum oxalate.
【作者单位】： Department
【分类号】：O643.36;TM277

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