Synthesis of MCM-22 Molecular Sieve Using Piperidine as an Organic Template
1.Shanghai Key Laboratory of Green Chemistry and Chemical Processes, Department of Chemistry, East China Normal
University, Shanghai 200062, China; 2.Shanghai Research Institute of Petrochemical Technology, Shanghai 201208, China
Abstract For synthesizing MCM-22 molecular sieves with different silica-alumina ratio, the effects of ingredient SiO2 to A12O3 ratio, alkali concentration, and the amount of organic template and crystallization-supporting agent, on the molecular sieves were studied systematically. The obtained MCM-22 samples were characterized by X-ray diffraction, scanning electron microscopy, inductively coupled plasma-atomic emission spectrometry, X-ray photoelectron spectroscopy and N2 adsorption-desorption. The results show that, MCM-22 molecular sieves with silica-alumina ratio of 25-500 could be successfully synthesized under this condition: using piperidine (PI) as the organic template and boric acid (BA) as the crystallization-supporting agent, n(OH-)/n(SiO2) of 0.03-0.20, n(PI)/n(SiO2)﹥0.03 and n(BA)/n(SiO2)﹥0.05. Moreover, the obtained molecular sieves using PI as the template have a smaller particle size and a larger specific surface area than those using hexamethyleneimine as the template.
