Catalytic oxidation of 1,2-dichloroethane over three-dimensional ordered meso-macroporous Co3O4/La0.7Sr0.3Fe0.5Co0.5O3: Destruction route and mechanism
Catalytic oxidation of 1,2-dichloroethane over three-dimensional ordered meso-macroporous Co3O4/La0.7Sr0.3Fe0.5Co0.5O3: Destruction route and mechanism
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三维有序介孔大孔Co3O4/La0.7Sr0.3Fe0.5Co0.5O3催化氧化1,2-二氯乙烷：破坏途径和机理
DOI：
10.1016/j.apcata.2018.01.013
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发表时间：
2018-03-05
影响因子：
5.5
通讯作者：
Zhu, Qing
中科院分区：
文献类型：
--
作者：
Tian, Mingjiao;He, Chi;Zhu, Qing
以1，2-二氯乙烷（1，2-DCE）为催化剂，采用PMMA为模板剂，设计并制备了三维有序介孔-大孔La0.7Sr0.3Fe0.5Co0.5O3（3DOM LSFCO）负载Co 3 O 4催化剂.采用XRD、FE-SEM、TEM、HAADF-STEM、低温N2吸附、XPS、H2-TPR、原位FT-IR等手段对样品的物化性能进行了表征。钙钛矿型氧化物的特殊3DOM结构促进了1，2-DCE分子与负载型催化剂表面吸附氧的有效和密切接触，并进一步加速了氧化还原过程。与纯LSFCO相比，所有Co_3O_4负载型催化剂均表现出上级的催化性能，反应速率从5.53 × 10 ~（-12）mol g ~（-1）s ~（-1）提高到2.29 × 10 ~（-11）mol g ~（-1）s ~（-1），E.从74.7下降到22.610 mol（-1）。其中，10 Co（3）O（4）/3DOM LSFCO催化剂由于其表面吸附氧最多，因此具有最好的催化活性、最高的抗氯中毒能力和最低的副产物浓度。CO2、CO、HCl和Cl-2是主要的氧化产物，同时也观察到一些典型的反应中间产物，如氯乙烯、1，1，2-三氯乙烷和三氯乙烯，特别是在3DOM LSFCO样品上。此外，基于气相色谱、原位红外光谱和在线质谱分析结果，提出了催化剂上1，2-DCE氧化的反应机理，认为Co 3 O 4/3DOM LSFCO是一种很有前途的氯代挥发性有机物完全去除催化剂。
Three-dimensional ordered meso-macroporous La0.7Sr0.3Fe0.5Co0.5O3 (3DOM LSFCO)-supported Co3O4 catalysts were designed and prepared via a PMMA-templating strategy for the total oxidation of 1,2-dichloroethane (1,2-DCE). The physicochemical properties of all synthesized samples were characterized by XRD, FE-SEM, TEM, HAADF-STEM, low-temperature N-2 sorption, XPS, H-2-TPR, and in situ FT-IR. The introduction of Co3O4 increases the generation rate of oxygen vacancy, playing a crucial role in adsorption and activation of oxygen species. The special 3DOM structure of perovskite-type oxide promotes 1,2-DCE molecules to effectively and intimately contact with the surface adsorbed oxygen over supported catalysts and further accelerates the redox process. Compared with pure LSFCO, all the Co3O4 supported catalysts show superior catalytic performance with reaction rate increases from 5.53 x 10(-12) to 2.29 x 10(-11) mol g(-1) s(-1) and E. decreases from 74.7 to 22.610 mol(-1). Amongst, the 10Co(3)O(4)/3DOM LSFCO catalyst exhibits the best catalytic activity, highest resistance to chlorine poisoning and lowest by-products concentration because of the largest amount of surface adsorbed oxygen. CO2, CO, HCl, and Cl-2 are the main oxidation productions, while some typical reaction intermediates such as vinyl chloride, 1,1,2-trichloroethane and trichloroethylene are also observed, especially over the 3DOM LSFCO sample. Furthermore, the reaction mechanism of 1,2-DCE oxidation over obtained catalysts was proposed based on the results of gas chromatography, in situ FT-IR, and on-line MS. It is believed that the Co3O4/3DOM LSFCO are promising catalysts for the total removal of chlorinated volatile organic compounds.