Zeolite synthesis in the NH 2(CH 2) 6NH 2Al 2O 3SiO 2H 2O system at 180 °C

Abstract

Crystallisation of the reaction mixture 20 C 6DM · x Al 2O 3 · 60 SiO 2 · 3000 H 2O (C 6DM = hexane- l,6-diamine; 0< x<0.5) in stirred reactors at 180 °C has been investigated. In all cases the product has the ZSM-48 framework structure and forms as spherical agglomerates of needle-shaped crystals. The crystallisation of the “aluminium free” ( x = 0) reaction mixture was followed by X-ray powder diffraction, pH, thermogravimetric analysis, and bulk density measurements. The product was thermally stable and on calcination it formed a hydrophobic silica molecular sieve.