Synthesis of MWW-type zeolite through seed-assisted interzeolite transformation from FAU zeolite
摘要
Developing the novel green routes for synthesis of important aluminosilicate zeolites is of significant for theoretical research and practical application. In this work, MCM-22 zeolite with MWW-topology was synthesized through seed-assisted interzeolite transformation from FAU zeolite without using additional organic template. The key influence factor to the synthesis process was investigated and the zeolite products were characterized by a series of modern techniques. It has been shown that not only the presence of MCM-22 seed, but also the appropriate SiO2/Al2O3 and Na2O/SiO2 molar ratio of starting synthesis gel with were crucial to synthesize pure MWW zeolite. The hexamethyleneimine template occluded in seed also played a key role in successful interzeolite transformation, but did not participate structure-directing of MWW product. Although the zeolite synthesized by interzeolite transformation showed lower surface area and pore volume compared with MCM-22 zeolite prepared by conventional route, the Pt modified sample exhibited promising catalytic performance in hydroisomerization of n-heptane.
Graphical Abstract