Synthesis of mesoporous silica-pillared clay by intragallery ammonia-catalyzed hydrolysis of tetraethoxysilane using quaternary ammonium surfactants as gallery templates.
Mesoporous silica-pillared montmorillonite (MMT) materials were synthesized by intragallery ammonia-catalyzed hydrolysis tetraethoxysilane (TEOS). The reaction involved hydrolysis and condensation of tetraethoxysilane in the presence of intragallery surfactants templates. Powder X-ray diffraction (XRD), N(2) adsorption-desorption isotherms, scanning electron microscopy (SEM) and Fourier transform infra-red (FT-IR) spectra were employed to characterize the mesoporous silica-pillared montmorillonite. These novel materials exhibited reflections corresponding to a basal spacing of 4.76-5.62 nm, a uniform pore size of 3.75-4.51 nm and large surface areas of 597.2-712.4 m(2)/g. And the porous structure and physical properties of silica-pillared montmorillonite derivatives remained stable after heating for 5 h at 700 degrees C in air. Our results indicate that surfactants play a decisive role in pore formation, because they act as micelle-like template during the hydrolysis of TEOS. These mesoporous silica-pillared montmorillonite materials exhibit excellent catalytic activity and selectivity for coker gas oil cracking reaction in comparison to normal MCM-41 and Al-MCM-41.
Li
Baoshan
B
State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029, PR China. bsli@mail.buct.edu.cn
Mao
Huihui
H
Li
Xiao
X
Ma
Wei
W
Liu
Zhenxing
Z