多孔二氧化钛薄膜的制备及其负载镍基甲烷化催化剂的性能研究

发布时间：2018-03-05 03:32

  本文选题：多孔　切入点：二氧化钛薄膜　出处：《太原理工大学》2017年硕士论文　论文类型：学位论文

【摘要】：微反应器通道狭小,传统催化剂在其中易团聚、堵塞。因此,将催化剂以薄膜形式负载并进行催化反应是解决该问题的有效方法。为了研究膜状催化剂的催化性能,本文选用制备方法较为成熟的多孔二氧化钛薄膜负载在铝丝基体表面,并使用浸渍法负载活性组分Ni,进行较为环保的CO甲烷化催化反应。其中分别研究了模板剂用量、陈化时间、热处理温度等制备条件对多孔二氧化钛薄膜的影响以及以该薄膜为催化剂载体制备的Ni基甲烷化膜催化剂的催化活性和稳定性研究。主要研究结果如下:(1)采用包含溶剂挥发诱导自组装的溶胶凝胶法与浸渍提拉镀膜技术,以嵌段共聚物F127为模板剂,在预处理的铝丝基体表面制备出了多孔二氧化钛薄膜。研究结果表明,在一定的溶胶配比(15mL乙醇、1mL去离子水、1mL盐酸、5mL钛酸丁酯和0.2mL乙酰丙酮)中,当F127的用量为1.0g、陈化时间为24h、热处理温度为400℃时制备的多孔二氧化钛薄膜具有均匀的多孔结构和最佳的结构特性,比表面积和孔容可分别达到127 m2·g-1和0.2139 cm3·g-1。(2)采用嵌段共聚物F127与P123为混合模板剂制备多孔二氧化钛薄膜可以优化薄膜的孔结构、增大比表面积和孔容。其中,当F127与P123用量为1.0g,质量比为3:1时,制备的二氧化钛薄膜具有更高的比表面积和孔容,可分别达到154m2·g-1和0.3031cm3·g-1。(3)通过该方法制备的二氧化钛薄膜在300℃、400℃、500℃热处理温度下均呈现出锐钛矿相,且模板剂的种类对其晶相不产生影响;在该溶胶凝胶体系中,模板剂的分解温度约为312℃。(4)以最优配比的混合模板剂制备的多孔二氧化钛薄膜作为催化剂载体,使用浸渍法负载活性组分Ni,形成Ni/TiO2甲烷化膜催化剂。在质量空速为3000 mL·g-1·h-1的条件下对催化剂的催化活性及其稳定性进行评价。研究结果表明:多孔二氧化钛薄膜表面成功负载活性组分Ni并制备了Ni/TiO2甲烷化膜催化剂,且还原前活性组分主要以NiO形式均匀负载在多孔薄膜表面;通过H2-TPR表征可以发现NiO能够与TiO2载体产生了强烈的相互作用,并形成NiTiO3;在反应温度超过400℃条件下,CO的转化率高于99%且其对CH4的选择性接近80%,并且在长达60h的稳定性评价中也具有良好的催化稳定性。
[Abstract]:The channel of microreactor is narrow and the traditional catalyst is easy to agglomerate and clog in it. Therefore, it is an effective method to solve this problem by loading the catalyst in the form of film and performing catalytic reaction. In this paper, porous titanium dioxide thin films with mature preparation method were used to support aluminum wire substrate, and the active component Ni was loaded by impregnation method to carry out the environmentally friendly methanation of CO. The amount of template was studied. Aging time, The effect of preparation conditions such as heat treatment temperature on porous titanium dioxide film and the catalytic activity and stability of Ni based methanation film prepared with the film as catalyst carrier were studied. The main results are as follows: 1). Sol-gel method with solvent volatilization induced self-assembly and dipping Czochralski coating, Porous titanium dioxide films were prepared on the surface of pretreated aluminum wires with block copolymer F127 as template. The results showed that in a certain ratio of 15 mL ethanol to 1 mL deionized water, 1 mL butyl titanate hydrochloride and 0.2 mL acetylacetone were prepared. When the dosage of F127 is 1.0 g, the aging time is 24 h and the heat treatment temperature is 400 鈩，

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