Non-aqueous preparation of LaPO4 nanoparticles and their application for ethanol dehydration

Abstract

Nanodispersed single phase monoclinic and hexagonal LaPO₄ materials have been prepared in polar non-aqueous solvents at room temperature, by means of precursor salts metathesis. The morphology and phase composition strongly depend on the nature of the non-aqueous solvent. Reaction in propylene carbonate produced hexagonal LaPO₄ nanorods; formamide gave a monolith gel with a monoclinic phase, whereas reaction in ethylene glycol led to the formation of a stable colloidal suspension of M-LaPO₄. The outstandingly high specific surface areas of the materials allow their use as soft acidic catalytic materials for highly selective dehydration of ethanol. Comparison of the catalytic properties reveals the importance of the phase polymorph, with hexagonal LaPO₄ demonstrating better catalytic performance than the monoclinic phase.