Al₂ O₃ -Phosphated green catalysts with high selectivity to ecological gasoline C=₈by dimerization of isobutene

In this paper, phosphated-alumina prepared from boehmite and phosphoric acid (1, 4, and 6 mmol of PO^3-₄ ) is proposed as a good alternative catalyst to obtain ecological gasoline by the reaction of dimerization of butenes in gas phase using a flow reactor and mild conditions (60° C and a C₄ /C= ₄ molar ratio = 1). XRD spectra of the samples showed the formation of the gamma-alumina phase in the solids. BET specific surface area values of the bare alumina were not notably modified when these materials were phosphate, from 180-m² /g to 170 m² /g. All the solids are mesoporous structured materials. FTIR pyridine-adsorption spectra showed the formation of strong Lewis acid sites, which remains stable even at desorption temperatures above 300° C. Bronsted acid sites were not observed on the materials.