甲烷在新型透氧膜反应器中直接转化制乙烯/芳烃耦合作用研究

Ethylene/aromatics production by the methane oxygen-free direct conversion is an innovative route for the highly efficient utilization of natural gas, however, the scientific and technological problems (ultra-high temperature activation, strongly endothermic process, and thermodynamic limit, etc.) encountered currently in the above-mentioned process seriously hinder the further explore and research on this reaction route. To decrease the reaction temperature, and to improve the methane conversion and ethylene/aromatics yield as well, using the novel mixed-conducting oxygen-permeable ceramic membranes as core assembly for the simultaneous in-situ oxygen supply and methane to ethylene/aromatics production shall be a scientific and novel solution. This project will rationally design and synthesize the novel cobalt-free oxygen-permeable membrane materials, and the oxygen permeability/permeation mechanism of the oxygen-permeable ceramic membranes will be investigated. The intrinsic relationships between the material compositions/microstructure and the structural stability/oxygen permeation properties will also be studied deeply. The membrane catalysis performance, kinetic characteristics, and stability for the integrated oxygen-permeable membrane reactors will be studied systematically. The structure-property relationships and coupling effect about the membrane separation/reaction process involved the oxygen distributed supply and methane to ethylene/aromatics production will be elucidated. The suggested membrane-based reactors with oxygen permeability and improved catalysis performance can couple in-situ oxygen distributed supply and methane to ethylene/aromatics reaction into such a highly integrated process. The proposed novel concept of the catalytic membrane reactors for methane to ethylene/aromatics production would be quite attractive and promising in the field of the highly efficient conversion of natural gas, and furthermore the theoretical and experimental fundamentals for the methane direct conversion in the mixed-conducting oxygen-permeable ceramic membrane reactors will also be established properly by the implementation of this project.

甲烷无氧直接转化制乙烯/芳烃是实现天然气高效利用的一条创新路径，但其所面临的科学与技术难题（如超高温活化、强吸热反应和热力学限制等）阻碍了对此过程的深入探索。采用以混合导体陶瓷透氧膜为核心组件的催化膜反应器从空气中原位供氧进行甲烷直接转化制乙烯/芳烃反应能为该过程提供新颖的科学解决方案。本项目设计合成新型的无钴透氧膜材料并探讨膜材料组成/微结构与其稳定性/透氧性能之间的内在科学关联。进一步构建新型催化膜反应器并深入研究甲烷直接转化制乙烯/芳烃分离与反应耦合过程的膜反应性能、动力学特性与稳定性，明确膜分离与反应一体化过程的构效关系及其耦合作用规律。这种具有膜分离与反应耦合及简洁工艺特点的新型催化透氧膜反应器对实现甲烷直接转化制乙烯/芳烃具有非常重要的科学价值和应用前景，并为天然气未来的高效直接转化利用奠定理论与实验基础。

当前随着富含甲烷的页岩气、生物沼气和天然气水合物等资源被大规模发现与开采，如何以储量丰富且价格低廉的天然气替代石油生产液体燃料和基础化学品成为学术界和工业界研究与开发的重点。甲烷无氧直接转化制乙烯/芳烃是实现天然气高效利用的一条创新路径，但其所面临的科学与技术难题阻碍了对此过程的深入探索及可能的应用潜力。本项目采用了以混合导体陶瓷透氧膜为核心组件的催化膜反应器从空气中原位供氧进行甲烷直接转化制乙烯/芳烃反应，为该过程提供新颖的科学解决方案。本项目设计并合成了一系列新型透氧膜材料，深入探讨了膜材料组成/微结构与其稳定性/透氧性能之间的科学关联，并成功构建了新型催化透氧膜反应器并深入研究了甲烷直接转化的分离/反应过程的膜反应性能、动力学特性与操作稳定性能，基本明确了膜分离与反应一体化过程的构效关系及其耦合相互作用的规律和本质。本项目已经取得了大量有价值的数据并解决了实验过程中面临的部分科学难题，建立在这些相关工作的基础上，已发表SCI论文6篇，申报发明专利5项，并获多项论文成果奖励，圆满完成了基金任务书的目标和要求。这种具有膜分离/反应耦合的催化膜反应器对实现甲烷直接转化具有重要的科学价值，并为天然气未来的高效转化利用奠定了基础，进一步的深入研究还很有必要。