Ceramic and Metal-Composite Membranes: Synthesis, Characterization and Reaction Studies

陶瓷和金属复合膜：合成、表征和反应研究

• 批准号: 9529172
• 负责人: Arvind Varma
• 金额: $ 24.66万
• 依托单位: University of Notre Dame
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1996
• 资助国家: 美国
• 起止时间: 1996-07-01 至 2000-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9529172&HistoricalAwards=false
• 关键词: Ceramic; Metal; Composite; Membranes; Synthesis

Abstract - Varma - 9529172 The eventual successful industrial application of inorganic membranes for simultaneous reaction and separation in membrane reactors depends on the ability to produce membranes of desired structural, catalytic and permeation properties. In many cases of practical interest, the optimal distribution of catalyst is a multiple-step function within the pellet and in the membrane. In catalytic membranes, precise distribution of the active element can be obtained using sequential slip-casting of active and inert sols. In these membranes, permeation studies indicate Knudsen flow with high fluxes. Synthesis procedures have been developed to prepare permselective metal composite membranes and microporous membranes with controlled active catalyst distributions. It has been demonstrated that for the same amount of catalyst and active surface area, nonuniform pellets have a higher overall conversion than uniform pellets. The PI plans to study metal composite and microporous ceramic membranes. For the case of metal composite membranes, he will determine the mechanism of film growth during electroless plating and osmosis, derive the deposition kinetics and develop a mathematical model based on the experimental findings. The synthesis chemistry and kinetics will be correlated with the film microstructure (using computer simulation) and membrane performance. On the basis of these results, the synthesis parameters will be optimized to yield membranes of desired properties. In the case of microporous membranes, the role of synthesis parameters (sol-gel and slip-casting characteristics) on the structure, permeation and catalytic properties of membrane materials will be determined to provide an understanding of the synthesis process. Further, methods will be developed to obtain and maintain high catalyst surface area per unit reactor volume. Finally, the stability of these membranes under the severe chemical and thermal conditions encountered in practice will also be examin ed. The performance of these membranes for reaction and separation, and that of a novel thin film composite catalytic membrane, will be evaluated using dehydrogenation (ethane to ethylene, ammonia decomposition) and partial oxidation (ethylene epoxidation) as probe reactions. A successful completion of this work will enhance the fundamental understanding of the relationship between synthesis and structure, and how the structure affects the material, permeation and reaction properties of the membrane.

摘要-Varma-9529172 在膜反应器中用于同时反应和分离的无机膜的最终成功的工业应用取决于生产具有所需结构、催化和渗透性质的膜的能力。 在实际感兴趣的许多情况下，催化剂的最佳分布是颗粒内和膜中的多步函数。 在催化膜中，活性元素的精确分布可以使用活性溶胶和惰性溶胶的顺序粉浆浇铸来获得。 在这些膜中，渗透研究表明具有高通量的努森流。 合成方法已被开发用于制备具有可控活性催化剂分布的选择性渗透金属复合膜和微孔膜。 已经证明，对于相同量的催化剂和活性表面积，非均匀粒料具有比均匀粒料更高的总转化率。 PI计划研究金属复合膜和微孔陶瓷膜。 对于金属复合膜的情况下，他将确定在化学镀和渗透过程中膜生长的机制，推导出沉积动力学，并根据实验结果开发一个数学模型。 合成化学和动力学将与膜微观结构（使用计算机模拟）和膜性能相关。 在这些结果的基础上，合成参数将被优化，以产生所需性能的膜。 在微孔膜的情况下，合成参数（溶胶-凝胶和粉浆浇铸特性）对膜材料的结构，渗透和催化性能的作用将被确定，以提供对合成过程的理解。 此外，将开发获得和保持每单位反应器体积的高催化剂表面积的方法。 最后，这些膜的稳定性下，在实践中遇到的苛刻的化学和热条件下也将examin。这些膜的反应和分离的性能，以及一种新型的薄膜复合催化膜，将评估使用脱氢（乙烷到乙烯，氨分解）和部分氧化（乙烯环氧化）作为探针反应。 这项工作的成功完成将加强对合成与结构之间关系的基本理解，以及结构如何影响膜的材料，渗透和反应性能。