【作者】 吴振涛；

【导师】 金万勤； 徐南平；

【作者基本信息】 南京工业大学 ， 化学工程， 2006， 博士

【摘要】 甲烷部分氧化（POM）制合成气膜反应过程将新型、高效的膜分离技术与催化反应过程耦合在一起,通过无机致密膜的选择性渗透作用向POM膜反应器动态提供反应所需要的纯氧,并实现了对反应过程的有效控制,因而成为天然气转化路线中的关键技术之一。该技术不仅显著降低天然气转化过程的投资和操作成本,还有效提高了POM催化反应过程的稳定性和操作的安全性,被认为是解决当前能源、资源和环境等重大问题的重要新兴技术之一。作为POM膜反应器的核心,混合导体透氧膜及膜材料不仅直接影响到反应器的性能,还在纯氧制备、氧泵、富氧燃烧以及燃料电池等方面展示出广阔的应用前景,相关的研究也逐渐形成了化工、催化、新材料交叉渗透的新领域。本文以天然气转化和综合利用为背景,在课题组前期工作的基础上,基于混合导体材料的组成、结构、制备和性能之间的关系,借助多种现代材料表征手段和实验室自行组建的高温氧渗透性能、POM反应评价装置,对混合导体透氧膜材料的设计、开发、合成和应用进行了一些新的基础性的探索,研究内容主要涉及以下三个方面:1、新型混合导体透氧膜材料的合成与性能研究新型混合导体透氧膜材料的设计和开发是提高透氧膜氧渗透性能和稳定性的根本途径。本文从混合导体透氧膜材料的组成和结构入手,通过在氧渗透性能优异但稳定性较差的SrCo_0.8Fe_0.2O₃-δ（SCF）中体相掺杂性质稳定且价格低廉的Al₂O₃,开发出Al₂O₃掺杂的SrCo_0.8Fe_0.2O₃-δ（SCFA）新型混合导体材料。在系统研究SCFA材料的组成、结构和性能随Al₂O₃掺杂量（1, 3, 5, 10wt.%）变化规律的基础上,选取对SCFA3（Al₂O₃掺杂量为3wt.%）片式膜的氧渗透过程及其在POM反应中的稳定性进行了考察。研究发现:（1） Al₂O₃在SCF中的固溶限（1223K）在3-5wt.%之间,且SCFA中钙钛矿相的组成和结构在固溶限附近发生了显著的变化:掺杂量低于固溶限时,SCFA为单相组成,Al³⁺离子进入SCF晶胞的间隙位并导致晶胞的轻微膨胀;掺杂量更多还原

【Abstract】 By combining the air separation and the catalytic partial oxidation of methane （POM） to syngas into one reactor, dense ceramic reactor technology, which is considered as the key of the one of the most promising routes for methane conversion, is expected to significantly reduce the capital costs of conversion of natural gas to liquid added-value products, and enhance the reliability and performance of the POM reaction. Based on the special mixed ionic-electronic conducting （MIEC） ability at high temperatures （typically above 973K）, MIEC oxides not only showed promising possibility as the membrane materials in catalytic membrane reactor, but also had wide applications in oxygen separation, oxygen-enriched combustion and solid oxide fuel cell （SOFC）. Related researches also gather the theories and techniques of Chemical Engineering, Catalysis and Materials, and are forming a new field in membrane science.In order to meet the needs of the conversion of natural gas in the engineering applications, the present researches started with the basic relationships among the composition, structure, synthesis and property of MIEC oxides with the aid of the advanced characterization methods of materials and the high temperature oxygen permeation / partial oxidation of methane （POM） measurements in our laboratory. Most of the attentions were focused on the design, exploitation, synthesis and application of MIEC oxides, which classified the present researches into three parts:1. Synthesis and properties of a novel Al₂O₃-doped SrCo0.8Fe0.2O3-δMIEC oxides Based on the theories of the material design in our group, a new series of Al₂O₃-doped SrCo0.8Fe0.2O3-δ（SCFA） MIEC oxides were synthesized by directly doping Al3+ into the SrCo0.8Fe0.2O3-δ（SCF） phase, a perovskite-type oxide with excellent oxygen permeability but limited stability （especially in the POM reaction）. By systematically investigating the dependences of composition, structure and property of SCFA on the doping amount of Al₂O₃ （1, 3, 5 and 10 wt.%）, we found that （1） The solid solubility of Al₂O₃ in SCF was between 3-5wt.%, near which the更多还原