甲烷干重整-部分氧化催化钙钛矿中空纤维膜制备与性能调控

Practical application of CO2 dry reforming of methane (DRM) is mainly disadvantaged by high energy consumption and catalyst coking inactivation. However, coupling the partial oxidation of methane (POM) with DRM in oxygen-permeable catalytic membrane reactor is a promising strategy to overcome these disadvantages and accomplish the efficient conversion of methane as well as the utilization of CO2 resources. In this project, synthesis of alkalescent mixed ionic and electronic conducting ceramic oxygen-permeable membrane materials with good resistance to CO2 toxicity, preparation of asymmetric structured hollow fiber membranes and catalytic membranes, fabrication of catalytic membrane reactors and development of mathematical model will be carried out in sequence. Detailed examination on the influence of perovskite materials composition and catalytic hollow fiber membranes structure for the DRM-POM coupled catalysis as well as in-depth research of the intrinsic mechanism for coupled catalysis in membrane reactors will be performed. Based on this project, the relationship between the composition, structure and performance of oxygen-permeable catalytic membranes, key technologies for the preparation of high performance oxygen-permeable catalytic membranes and membrane reactors, and the mechanism of the DRM-POM coupled catalysis will be revealed and clarified. In addition, precise regulation of the coupled catalysis will be achieved. The development of high efficiency, low-cost and stable membrane reactor with application prospects will provides theoretical basis and technical support for the efficient conversion of methane and the utilization of CO2 resources.

甲烷干重整（DRM）耗能大、催化剂易积炭失活，限制了其实际应用，通过耦合钙钛矿透氧膜催化甲烷部分氧化（POM）降低反应能耗并解决催化剂积炭失活问题，实现甲烷高效转化和CO2资源化利用。项目合成具有良好抗CO2毒化性能的弱碱性混合导体陶瓷透氧膜材料，制备非对称复合结构中空纤维透氧膜，负载DRM-POM催化剂制备耦合催化膜，设计制备催化膜反应器，建立催化膜反应器数学模型，详细考察钙钛矿材料组成和中空纤维催化膜结构对DRM-POM耦合催化的影响；深入研究膜反应器DRM-POM耦合催化反应的内在机理和规律。通过该项目研究，揭示透氧催化膜的组成、结构与性能的关系，掌握高性能透氧催化膜和膜反应器制备的关键技术，阐明DRM-POM耦合催化反应过程机理，实现耦合催化性能的精确调控，为甲烷高效转化和CO2资源化利用提供理论依据与技术支持。

对于优化能源结构、减少环境污染具有重要意义的甲烷部分氧化（OCM）和甲烷干转化（DRM）是天然气直接转化为合成气或者制氢的重要途径，其实际应用受热力学平衡转化率低、催化剂快速结焦失活限制。本项目研究开发一种具备优良透氧性能同时耐CO2的多功能陶瓷催化膜和膜反应器，通过分布供氧和H2分离突破反应热力学平衡限制，提高氢气产率，利用膜的透氧/水特性抑制积碳，提高稳定性。.项目首先通过一步热处理，制备了铋和锆共掺杂的BaCo0.95-xBi0.05ZrxO3-δ（x=0.00-0.20）中空纤维膜，研究了Zr掺杂和CO2对膜性能的影响。BaCo0.85Bi0.05Zr0.1O3-δ（BCBZ）膜氧渗透性能最佳，1000℃时的氧渗透通量5.07 mL min-1 cm-2。膜进料侧CO2对氧渗透毒化作用更强，CO2对膜结构的侵蚀主要发生在渗透侧。.使用多孔BCBZ材料将BCBZ中空纤维膜进行集束，同时提高膜的机械性能和氧渗透性能。利用CFD软件对陶瓷中空纤维膜组件进行了流体力学分析。当9根中空纤维膜集束时，平均机械强度最大达到120.74 MPa。渗透侧的真空度比进料压强对氧渗透的影响更显著，增加膜长度和膜的间隙，会提高氧气回收率。.在La0.6Sr0.4Co0.2Fe0.8O3-δ中空纤维膜内外表面涂覆OCM催化剂和透氧催化剂，在BaCe0.85Tb0.05Co0.1O3-δ中空纤维膜内表面负载甲烷脱氢偶联（DCM）催化剂，所制备的膜反应器的氧/氢渗透速率有所提高。氧-氢渗透和OCM、DCM之间既相互促进又相互制约。微量O2与H2、CO和C2烃可在膜反应器中共存。水蒸汽可提高甲烷转化率，增加氢气产量。.采用相转化和烧结技术制备了Fe和Sc共掺杂的BaCe0.7Fe0.3-xScxO3-δ钙钛矿陶瓷中空纤维膜，研究了材料组成对膜性能的影响。1000℃时，BCFSc20（x=0.20）膜的H2、O2和水蒸气渗透通量分别达到0.32、0.20和0.065 mL min-1 cm-2，稳定性良好。当外加电压小于1.5V时，所形成的水蒸气泵处于稳态。.通过建模和实验研究了Sm0.2Ce0.8O1.925–SrCo0.4Fe0.55Zr0.05O3-δ双相陶瓷膜的氧渗透性能。700-750°C，氧渗透主要受表面交换反应的限制。800-950°C，氧渗透同时受体扩散和表面交换反应的控制。