低温催化裂化多产丙烯金催化剂构效关系和反应机理研究

纳米金粒子、金原子簇或金配合物催化不同化学反应的研究已非常活跃，而在重油催化裂化的高温和复杂混合反应物体系的研究几乎是无人问津。本项目拟在我们前期微孔微米级ZSM-5载金催化剂较低温度催化裂解柴油反应结果的基础上，利用分子筛规整孔道的限域功能定向沉积纳米金粒子及原子簇于分子筛孔道内以制备高温稳定性较好的微孔、介孔纳米和微米ZSM-5分子筛载金催化剂；以轻柴油为原料，以辛烷值较低的C8、C12,和C16的直链烷烃和烯烃为模型化合物，考察系列Au/ZSM-5催化剂在不同反应温度下的催化裂解活性、丙烯选择性和反应稳定性；通过同位素标记原位反应等现代分析方法，比照惰性载体载金催化剂的催化裂化反应结果，探索和阐明在复杂反应体系下金催化裂化多产丙烯的构效关系和反应机理，为揭示苛刻反应条件下的金催化作用机制，开发低温高裂化活性、高丙烯选择性、高稳定性的催化剂（及助剂）奠定实验和理论基础。

Nanogold particles, clusters and complexs are widely used to catalyze different types of reactions. However, up to now, there is little study for using gold catalysts in catalytic cracking process which involves high temperature and complex reactant mixture. The project proposed here is based on our recent results for gold catalysts supported on micro-/micron ZSM-5 zeolite for catalytic cracking of light diesel oil at lower temperatures. The microporous, mesoporous nano- and micron ZSM-5 zeolite are synthesized and gold nanoparticles are deposited inside of the zeolite pores by the use of confinement function, resulting in stable Au catalysts at high temperature. The light diesel is used as the feed and C8, C12,and C16 straight chain alkanes and alkenes as model compounds. The cracking activity, propylene selectivity and activity stability of Au/ZSM-5 catalyst at different reaction temperatures are evaluated. By using modern analytical technologies such as in situ reaction and isotopic labeling and by comparing the corresonding performance on Au catalyst with inert support for the cracking reaction and some of current results,the structure-reactivity relationship and reaction mechanism of nanogold catalysts at high temperature and complex system are explored and clarified. This is important not only in determining the mechanism of gold catalysis under extremely harsh reaction conditions, but also in developing novel cracking catalyst or additive with high cracking activity at low temperature, high propylene selectivity, and high stability.