Nickel substituted tungstophosphoric acid supported on Y-ASA composites as catalysts for the dehydration of gas-phase glycerol to acrolein

We report a series of nickel-substituted tungstophosphoric acid on Y-ASA (NixH3-2xPW/Y-ASA, x = 0, 0.5, 1.0, 1.5), prepared by a (co)impregnation method, which are efficient catalysts for dehydration of gas-phase glycerol to acrolein. Characterization including FT-IR, TEM-EDS and XRD demonstrated that the NixH3-2xPW nanoparticles were successfully immobilized onto the Y-ASA support. Pyridine IR (Py-IR) and H2-TPR studies reveal that the acidity and reducibility of NixH3-2xPW/Y-ASA catalysts are Ni content-dependent. The total acid content, pore size and reducibility were improved for NixH3-2xPW/Y-ASA (x = 0.5, 1.0, 1.5) as compared to H3PW/Y-ASA. The elaborately fabricated Ni1.0HPW/Y-ASA has a maximum acid content and an optimized reducibility. Accordingly, Ni1.0HPW/Y-ASA exhibits the best catalytic performance when examined as catalysts for the dehydration of gas-phase glycerol to acrolein, showing the highest selectivity to acrolein of 74.5% as 81.8% of glycerol was converted.