ZSM-5 and ferrierite synthesized by magadiite conversion method in 1, 6-hexamethylenediamine system

摘要

ZSM-5 and ferrierite have been successfully synthesized by magadiite conversion method using 1, 6-hexamethylenediamine (HMD) as structure directing agent. The binary crystallization phase diagram was obtained by various reactant ratios of H2O/SiO2 and SiO2/Al2O3 and the regular phase transformations were also demonstrated. The optimized reactant HMD/SiO2 ratio was 0.6. The high crystalline ZSM-5 was composed of coffin-shaped crystallite with length of 4 gm where as ferrierite exhibited platelike crystallite having a diameter of 8 mu m. The C-13 MAS NMR spectra revealed that the HMD which can be used as a structure directing agent in the conversion process was held tenaciously inside the pores of ZSM-5 and ferrierite. The formula of as-obtained ZSM-5 and ferrierite could be vertical bar K-2.1(C6H16N2)(4.2)(H2O)(16.9)H-8.4 vertical bar[Si85.5Al10.5O192] and vertical bar K-2.1(C6H16N2)(0.9)(H2O)(6.4)H-2.2 vertical bar[Si31.7Al4.3O72] respectively based on the compositional analysis. More over the structure of prepared ZSM-5 and ferrierite were collapsed when the temperature rose up to 1200 degrees C and 1100 degrees C respectively; both are exceptionally stable towards strong acid. (C) 2015 Elsevier Inc. All rights reserved.