论文总字数：20490字

摘 要

多孔阳极氧化铝（Porous Anodic Alumina , PAA）技术，因其拥有的金属自生长膜，被认为是可以解决整体式催化材料的催化剂涂层剥落这一瓶颈的关键技术。然而现有的PAA催化材料，孔道结构单一，比表面积较小等缺陷，限制了其在催化反应中的应用。在这背景下，本文用自制的阳极氧化装置研究了PAA孔径、膜厚和比表面积随扩孔温度、扩孔时间的变化规律，从而获得最佳的扩孔条件。在此基础上，研究了后续的水热处理（Hydro Thermal Treatment,HTT）对PAA孔结构及比表面积的影响规律。

本文以单一的草酸为电解液开始研究，分别在不同氧化时间 (2 h、4 h、8 h、10 h、16 h)下制备了有序PAA 膜，并分析了其孔径、膜厚与氧化时间的关系，发现随着氧化时间的增长，膜厚增大，孔径基本不变。同时，在40 V，8 h的草酸中制备的PAA 模板上，通过BET以及SEM 电镜技术，考察了扩孔处理（Pore Widening Treatment,PWT）和水热处理对该PAA 比表面积及孔道的影响。结果发现，水热反应后，PAA 膜的孔壁上原位相变生长出拟薄水铝石层，再焙烧处理可大幅提高PAA 膜的比表面积。但是，伴随着水热的封孔效应，丧失了PAA 膜的良好的多孔结构，为了解决这一矛盾，所制备的PAA 就需要大孔径。

关键词：多孔阳极氧化铝 阳极氧化 催化材料

Study on the hydration mechanism of porous anodic alumina catalyst support

Abstract

Porous Anodic Alumina (PAA) technology has been expected to solve the catalysts layer delamination problem for the monolith catalysts because of its in-situ growth membrane. However, the PAA is limited to the catalytic application, for its low surface area,pore structure unitary and etc.. Under this background, we studied the relationships between the pore size, the thickness of film and BET surface area of PAA to obtain the best condtions for pore widening treatment by using home-made PAA equipment. Further, the effect of hydro-thermal treatment (HTT) of prepared PAA over its pore structure and surface area was also discussed here.

With the oxalic acid as the electrolyte, at different time (2,4,8,10,16h), a series of ordered PAA was prepared. The relationship between the pore size, the thickness of the film and the oxidation time was analyzed, and the pore size and the film thickness increased with the increase of oxidation time. Further, PAA templates were prepared on at 40V in oxalic acid for 8 hours.We investigated the effects of BET surface area and pore structure of PAA by the pore widening treatment (PWT) and hot water treatment by BET and SEM. It was concluded that by calcining the in-situ growed boehmite gel on the pore surface during the hot water treatment, the surface of PAA was significantly increased. Nevertheless, the pore sealing phenomenon during the hot water treatment destroyed the porous structure of PAA. As an approach, a PAA with larger pore size will be required.

Keywords: Porous Anodic Alumina; Anodic oxidation; Catalytic materials

目 录

摘要 I

Abstract II

第一章 引言 1

1.1 整体式催化剂概述 1

1.1.1 整体式催化剂的结构及性能 1

1.1.2 整体式催化剂的特性 3

1.1.3 整体式催化剂载体的制备方法 3

1.2 多孔阳极氧化铝概述 4

1.2.1 多孔阳极氧化铝的发展 5

1.2.2 多孔阳极氧化铝的结构模型 6

1.2.3 多孔阳极氧化铝在催化中的应用 8

1.3 本文研究内容 8

第二章 PAA膜的制备 10

2.1 实验原料与设备 10

2.2 PAA样品的制备 11

2.2.1 PAA的制备 11

2.2.2 PAA在草酸中扩孔 13

2.2.3 PAA的水热反应 13

2.3 PAA树脂样 13

第三章 PAA扩孔及水热条件的优化 14

3.1 PAA模板 14

3.2 扩孔条件的优化 15

3.3 水热条件的优化 19

3.3.1 水热温度 19

3.3.1 水热时间 19

第四章 总结与展望 21

参考文献 23

致谢 27

第一章 引言

1.1 整体式催化剂概述

传统的颗粒状催化剂具有易磨损、整体效率低、难以回收、在应用过程中容易堵塞催化剂活性位甚至堵塞反应器等缺陷，整体式催化剂在某一方面不仅结合了催化剂的设计元素，更结合了反应器设计的要求，解决了传热效率低，整体效率低等根本问题。整体式催化剂具有传质传热好、床层压降低、紧凑小型、工程放大简单等优点，它兼具催化剂和反应器的特点和性能，有利于提高催化活性和选择性。近几十年来，整体式的催化剂不仅在汽车尾气处理氮氧化合物^[1]，VOCs催化燃烧等环保方面有着广泛的应用，其在多相有机合成的化工生产领域也有着应用。

1.1.1 整体式催化剂的结构及性能

整体式的催化剂一般会由规整载体、可以涂覆的涂层和起催化作用的活性组分组成。

（1）整体式催化剂的载体

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