Catanionic-surfactant templated synthesis of organized mesoporous γ-alumina by double hydrolysis method

Abstract

Organized mesoporous γ-alumina samples were prepared by cationic-anionic double hydrolysis (CADH) method using the mixture of cationic and anionic surfactants as template. The intermediate aluminum oxyhydroxides were characterized by XRD, SEM, TEM, FT-IR and TG. Boehmite could easily form under the given synthetic conditions, where an increase in the crystallization temperature favored the formation of well-crystallized boehmite. After the calcination, organized mesoporous γ-Al2O3 was obtained by dehydroxylation between AlOOH octahedron structures. After being characterized by N2 adsorption–desorption, the obtained γ-Al2O3 was of excellent textural properties, i.e., large pore volume (0.79 cm3 g−1), and large pore size (12.1 nm) with narrow pore size distribution which can be used as good candidates for catalyst support in the processing of heavy petroleum. In this modified CADH method, the mixture of cationic and anionic surfactants plays a key role in the formation of relatively large mesopore.