Ceramic Membranes for Catalytic Liquid Reaction Application

陶瓷膜具有良好的孔径均匀性、良好的热性能和力学性能。它们可以在高温(1000℃)和化学工业中常见的腐蚀性环境中使用。它们还有一个额外的优点，那就是可以进行热处理(500℃)、蒸汽清洗和灭菌。由于不利的热力学、产物抑制或不良副反应，许多工业催化反应表现出较低的转化率和/或产率。这反过来又需要更苛刻的操作条件(这反过来需要更高的催化剂替换率)和昂贵的分离操作。催化膜反应器是膜是反应器不可分割的一部分，在单一单元操作中将反应和分离结合在一起。这种单元的优点在于，膜提供了与反应并行的对一个或多个产物和/或稳定中间体的选择性去除，从而推动反应连续地朝向产物侧，并导致更高的转化率。随着转化率的提高，该过程可以在较低的压力和温度下运行，从而延长催化剂寿命，减少回收，并减少下游分离要求。该膜还可以控制表面浓度，从而控制选择性和产物分布。测试陶瓷膜反应器技术在石油和沥青质加氢加工领域的适用性是该工业大学合作研究(IUCR)项目的主要目标。本文将研究两种氧化铝陶瓷膜：铝阳极氧化膜和溶胶-凝胶法制备的氧化铝陶瓷膜。这两种膜具有几乎单峰的孔径分布，并显示出良好的分离功能。它们具有不同的表面性质和不同的孔结构，因此可以具有不同的能力和/或用途。

Ceramic membranes have good pore size uniformity, and good thermal and mechanical properties. They can be used at high temperatures (1000>C) and in the corrosive environments often found in the chemical industry. They have the additional advantage that they can be thermally treated (500>C), steam cleaned and sterilized. Many industrial catalytic reactions show low conversion and/or yields due either to unfavorable thermodynamics, product inhibition or undesirable side reactions. This in turn necessitates more severe operating conditions (which in turn require higher catalyst replacement rates) and costly separation operations. Catalytic membrane reactors, units in which the membrane is an integral part of the reactor, combine reaction and separation in a single unit operation. Such units have the advantage that the membrane provides for selective removal of one or more products and/or stable intermediates in parallel with the reaction, thus driving the reaction continuously towards the product side and resulting in higher conversions. With higher conversion, the process can be run at lower pressure and temperature, resulting in longer catalyst life, reduced recycle, and reduced downstream separation requirements. The membrane also enables control of surface concentrations and therefore selectivity and product distribution. It is the primary goal of this Industry University Cooperative Research (IUCR) project to test the applicability of ceramic membrane reactor technology in the area of oil and asphaltene hydro processing. Two types of alumina ceramic membranes will be studied, membranes prepared by anodic oxidation of aluminum and membranes prepared by the Sol-Gel technique. Both kinds of membranes have a virtually unimodal pore size distribution and show excellent separatory functions. They have different surface properties and different pore structures and could therefore have different capabilities and/or uses.