Synthesis of matal chloride-impregnated aluminium oxide-pillared clay for acid catlyzed reations

Abstract

Iron oxide-pillared clays such as iron oxide-pillared bentonite, iron oxide- pillared hectorite and iron oxide-pillared taeniolite were synthesized by the intercalation of iron (III) chloride into clay interlayers and calcination at 300 [Celsius degree] for 5 h. Aluminium oxide-pillared bentonite was prepared by the intercalation method and calcination at 500 [Celsius degree] for 1 h. The impregnation with metal chloride (LaCl[Subscript 3], CeCl[Subscript 3], NdCl[Subscript 3], GdCl[Subscript 3], YbCl[Subscript 3] and DyCl[Subscript 3]) was carried out with calcination at 450 [Celsius degree] for 4 h. The synthesized clays and raw clays were characterized using powder X-ray diffraction, N2 adsorption-desorption, temperature programmed desorption of ammonia and Inductively Coupled Plasma Optical Emission Spectrometry techniques. These synthesized catalysts were used for acid-catalyzed reactions (1) Friedel-Crafts acylation, (2) the conversion of epoxides to acetonides, and (3) isomerization reaction. The catalytic activity of synthesized clays was compared with raw clays. The synthesized clays provided significantly higher yield than raw clays in all types of clays. The optimized conditions for acid-catalyzed reaction were disclosed. Those reactions could smoothly be proceeded in the presence of synthesized clays to furnish the corresponding products in good to excellent yield and selectivity of products in all reactions under mild conditions.