含氟体系对SAPO-31分子筛结构与表面性质的影响

Effects of Fluorine System on Structure and Surface Properties of SAPO-31 Molecular Sieve

双功能催化剂催化的加氢异构化反应是生物柴油制备工艺的关键步骤。作为载体和提供酸性中心,分子筛对催化剂的催化性能至关重要。在含氟体系下,合成了SAPO-31分子筛,并利用XRD、SEM、29Si MAS NMR、N2物理吸附以及TPD-NH3等分析手段,对合成分子筛的结构与表面性质进行了表征。探讨了含氟和无氟体系下合成SAPO-31的形成机理。

The hydroisomerization reaction catalyzed by bifunctional catalysts is a key step in the preparation of biodiesel. As a carrier and an acidic center, the molecular sieves are critical to the catalytic performance of catalysts. The SAPO-31 molecular sieves arc synthesized with the reac- tion system containing HF, and the structure and surface properties of as-prepared SAPO-31 are characterized by XRF, XRD, SEM, 29Si MAS NMR, N2 physical adsorption and TPD-NH3 analysis method. The formation mechanism of SAPO-31 with fluorine and fluorine-free system is discussed.