新型烷烃脱氢制烯烃催化剂及循环流化床反应器基础研究

Catalytic dehydrogenation of light alkanes is beneficial to the comprehensive utilization of oil and gas because it can not only convert alkanes effectively to high value alkenes, but also provide cheap hydrogen for the hydrogenation processes. However, expensive Pt-based catalysts and poisonous chromia-based catalysts have restricted the widely application of dehydrogenation technologies. Sulfide nickel catalysts, relatively inexpensive, possess high activity and selectivity to the corresponding alkenes in dehydrogenation processes. In this project, the work will mainly focus on the following aspects: investigating the relationship between the structure of the catalysts and the performance of isobutane dehydrogenation over supported nickel-based catalysts, identifying the active phase of sulfide catalysts, studying the deactivation mechanisms and regeneration measures of the catalysts, comparing the interactions between the catalysts and alkane or alkene molecules before and after sulfidation, and carrying out the basic engineering researches concerning the circulating fluidized bed reactor suited to the sulfide catalyst. This program will not only provide practical guidance for the development of novel technology for alkane dehydrogenation, but also fill up domestic blank in alkane dehydrogenation technology. Therefore, it is of great significance.

发展低碳烷烃脱氢制高附加值低碳烯烃，还可为炼厂提供廉价的氢源，提高油气资源的综合利用水平。铂基催化剂价格昂贵，三氧化二铬催化剂对环境污染严重，制约了异丁烷脱氢技术的推广。硫化型Ni基催化剂用于烷烃催化脱氢过程，价格相对低廉，脱氢活性和烯烃选择性高。本项目拟开展：负载型Ni基催化剂组成、结构与异丁烷脱氢反应性能关系的研究，并确定硫化后催化剂的活性物种；催化剂的失活机理与再生方法的研究；探索硫化型Ni基催化剂可提高异丁烷脱氢制异丁烯选择性的原理；在以上研究基础上开发一种具有高效催化异丁烷脱氢制异丁烯性能的硫化型Ni基催化剂，并开展与之配套的循环流化床反应器的工程化基础研究工作。本项目对于指导烷烃脱氢制烯烃新技术的开发，填补我国在这方面的技术空白，具有重要的意义。

烷烃脱氢作为合理利用丰富低碳烷烃资源、制备高附加值低碳烯烃的一条重要途径，日益受到人们的重视。目前已工业化的脱氢技术均采用催化脱氢路线，所用催化剂非Pt即Cr2O3。前者价格昂贵，后者污染环境，制约了烷烃脱氢技术的推广。本项目对新型低价硫化型Ni基催化剂用于烷烃催化脱氢的作用机制及其配套循环流化床反应器的工程化基础研究工作取得了系列重要研究结果。主要包括以下几个方面：（1）对比研究了硫引入前后Ni基催化剂的脱氢反应性能，构建了负载型Ni基催化剂组成、结构与异丁烷脱氢反应性能之间的关系，并确定了硫化后催化剂的活性物种；（2）采用原位红外测定了异丁烷和异丁烯在硫化前后Ni基催化剂上的吸附状态，利用在线质谱建立了高温瞬变脱附热测定方法，明确了硫化型Ni基催化剂可提高异丁烷脱氢制异丁烯选择性的原理；（3）开发了具有高效催化异丁烷脱氢制异丁烯性能的硫化型Ni基催化剂；（4）开展了与硫化型Ni基催化剂配套的循环流化床反应器的工程化基础研究工作，根据反应和冷模实验结果确定合适的反应器结构和催化剂的理想流化状态，解决了原料与催化剂高效、均匀接触的问题。项目执行期间发表论文21篇，SCI收录19篇。申请专利12项，授权7项。本项目拓宽并加深了人们对催化脱氢反应规律的认识，对于指导新型烷烃脱氢催化剂及其技术的开发具有重要的意义。