A solid acid of tungsta-niobia more active than aluminosilicates for decompositions of cumene, ethylbenzene, and toluene

A solid acid of tungsten-niobium oxide was obtained by evaporating the water from a mixed solution of ammonium metatungstate and niobium ammonium oxalate in water in the ratio 7:1 of W to Nb, followed by calcining in air at 400 °C. The catalytic activity of the solid acid for decompositions of toluene, ethylbenzene, and cumene was higher than those of tungstated zirconia, mordenite, and silica-alumina. The chief ingredient of Nb in the mixture was less effective. The acid strength was estimated by the heat of Ar adsorption to be 18.1 kJ mol−1, the value being coincident with that of H-mordenite (18.3 kJ mol−1).