催化剂的传质性能影响其催化反应性能，尤其是活性中心的可接近性是催化剂表现出活性的关键。本课题拟在纳微尺度范畴内，以流化催化裂化（FCC）催化剂体系为研究对象，结合HRTEM、N2吸附、NH3-TPD、化学吸附及程序升温技术等多种手段，采用频率响应技术(FR)、智能重量分析-质谱仪（IGA-MS）系统研究烷烃、烯烃、芳烃和硫化物等分子的吸附扩散行为，并采用原位吸附不同分子尺寸碱性探针分子的红外光谱技术（in situ FT-IR），系统研究催化剂酸中心的可接近性。探讨催化剂中发生的各种传质过程及各过程间的相互影响和协调作用，考察传质过程对催化剂活性中心可接近性及不同活性中心间协调机制的影响。为新型催化材料和催化剂的进一步开发应用提供坚实的理论支持。

The mass transfer performance and the accessibility of the active sites are the key factors effecting the catalytic properties of catalysts. In this proposal, with fluid catalytic cracking (FCC) catalysts and their main components such as Y and ZSM-5 zeolites being taken as research objects, combined HRTEM, N2 adsorption, NH3-TPD, chemisorption and other temperature programmed techniques, the adsorption and diffusion behaviour of some alkanes, olefins, arenes and sulfur compounds on those catalytic materials will be investigated systematically in micro-/nano-scales by using the FR and IGA-MS techniques. Besides, in situ FT-IR spectra of adsorbed basic probe moleculars with different size will be utilized to study the accessibility of the acidic sites. Studies of the effect of the mass transfer processes on the accessibility of the catalytic active sites of the catalysts and on the synergism of the different catalytic active sites are also involved. The results will lay theoretical foundations for the development of novel catalytic materials and catalysts.