CGO-SCYb无机陶瓷膜的制备、气体渗透性能及甲烷芳构化反应研究

Inorganic ceramic gas permeable has a wide and promising application in the field of chemical engineering. In order to solve the problems of low yield and carbon deposition in catalytic aromatization of methane, a CGO-SCYb composite ceramic dense membrane will be developed to inhibit carbon deposition and break the limitation of reaction thermodynamics and kinetics. In specific, the permeation fluxes of composite membranes with different ratio of CGO and SCYb will be measured at different temperature and atmosphere conditions to study the effect of two compositions on structure, sintering, conductivity and stability. Through optimization process, an high-efficiency and stable oxygen-hydrogen permeable CGO-SCYb dual phase membrane will be obtained. After the investigation and optimization on the influence of catalytic coating on membrane stability and permeation performance, methane aromatization will be carried out by the composite membrane reactor. The effects of temperature, methane concentration in feed, steam flowrate in permeate side on reaction conversion and product yield will be investigated respectively, so as to study the reaction mechanism in composite membrane reactor. The development of oxygen-hydrogen permeable membrane reactor and its application on methane aromatization reaction will be promote the research of methane conversion technology, and conducive to the effective utilization of natural gas, coal-bed gas, shale gas and so on.

无机陶瓷气体渗透膜在化工领域具有广阔的应用前景，针对甲烷芳构化反应中芳烃收率低和催化剂易失活的问题，本项目拟开发一种Ce0.9Gd0.1O2-δ-SrCe0.95Yb0.05O3-δ (CGO-SCYB)既透氧又透氢的陶瓷致密膜，从而较好的结合甲烷无氧芳构化和有氧芳构化各自的优点，进而提高芳烃产率，又减缓催化剂积碳。通过考察不同CGO和SCYb组成的陶瓷膜在不同条件下的渗透通量，阐明CGO和SCYb对膜的结构和混合电导率的影响，优化组成，获得渗透性能好、结构稳定的透氧透氢陶瓷膜。研究催化涂层对陶瓷膜渗透性能和稳定性的影响，获得最优催化膜反应器，并应用在甲烷芳构化反应，考察温度、甲烷浓度等对反应转化率和收率的影响，探索透氧透氢陶瓷膜反应器实现甲烷芳构化的反应机制，丰富甲烷芳构化反应的研究，对天然气、煤层气、页岩气等资源的有效利用带来帮助。

无机陶瓷气体渗透膜在化工领域具有广阔的应用前景，然而目前常见的透氢或者透氧膜材料存在着渗透性能较低或者催化反应条件下的稳定性较差的问题，针对该难题，本项目开发了高稳定性和高渗透通量的透氧/透氢致密陶瓷膜(CGO-SCYb、CGO-SCF和CPO-PSF)。通过考察不同相组成对CGO膜材料的微观结构和渗透性能的影响，获得了渗透性能较高的透氧和透氢陶瓷膜，其在 940℃温度下的透氢量和透氧量分别达到1.08mL·min-1·cm-2和0.75mL·min-1·cm-2。随后考察了不同催化反应条件对致密陶瓷膜的稳定性影响，发现该类陶瓷膜材料具有较高的抗CO2稳定性和抗还原稳定性，并考察了该类陶瓷膜在催化反应条件下的长期稳定性，最后研究了膜材料CGO的加入对甲烷芳构化反应性能的影响，研究发现CGO材料的加入不仅可以提高甲烷转化率和芳烃产率，而且减缓了催化剂Mo/HZSM-5积碳，提高了催化剂的稳定性，与未添加陶瓷膜材料相比，700oC时，甲烷转化率提高了71%，同时在反应100min后，甲烷转化率依然保持在10%，芳烃产率提高了2倍，丰富了甲烷芳构化反应的研究，对天然气、煤层气、页岩气等资源的有效利用带来帮助。