RUB-13分子筛的合成及其甲醇制烯烃催化性能

采用水热法合成RUB-13分子筛，探讨了有机模板剂（OSDA）、硅源、晶化温度和水硅比等制备条件对RUB-13分子筛晶体结构的影响，考察了RUB-13分子筛在甲醇制烯烃（MTO）反应中的催化性能。结果表明，采用1，2，2，6，6-五甲基哌啶（PMP）为有机模板剂、白炭黑为硅源，在晶化温度为170℃的条件下，选择H₂O/Si比为100和80时可分别合成出高纯度的低硅铝比（Si/Al=100）和高硅铝比（Si/Al=200）的RUB-13分子筛晶体，且晶粒呈棒状形貌。H-Al-B-RUB-13（Si/Al=200）分子筛用于催化甲醇制烯烃反应时，在400℃下表现出高的低碳烯烃选择性（C_2-5⁼选择性达97.8%，丙烯选择性为54.5%），优于传统的H-SAPO-34和H-ZSM-5分子筛催化剂。

Synthesis of RUB-13 zeolite and its catalytic performance in the conversion of methanol to olefins

RUB-13 zeolites were synthesized by hydrothermal method. The effect of organic structure-directing agent (OSDA), silica source, crystallization temperature and Si/H₂O ratio on the crystal structure was investigated and the catalytic performance of H-RUB-13 in the conversion of methanol to olefins (MTO) was evaluated. The results indicate that with 1,2,2,6,6-pentamethylpiperidine (PMP) as OSDA and fumed silica as silica source, pure and highly crystalline RUB-13 zeolites with a Si/Al ratio of 100 or 200 can be successfully synthesized by crystallization at 170 ℃, with a H₂O/Si ratio of 100 or 80 in the synthesis gel, respectively. The crystals of the synthesized RUB-13 zeolites display a thin rod-like morphology. As a catalyst in MTO, the high-silica H-Al-B-RUB-13 (Si/Al=200) zeolite exhibits unprecedentedly high selectivity to light olefins at 400 ℃ (54.5% to propene and 97.8% to C_2-5⁼), much better than the traditional H-SAPO-34 and H-ZSM-5 zeolites under similar conditions.