HETEROPOLY-ACIDS, AND THEIR PRODUCTION AND USE

摘要

HETEROPOLY-ACIDS, AND THEIR PRODUCTION AND USE A heteropoly-acid of the formula: H3+x(PMo12-xVxO40).nH2O wherein x and n are numbers satisfying respectively the equations: 0A?xA?3 and nA?6, and comprising phosphorus as the central atom and molybdenum or molybdenum and vanadium as the coordinating atoms, or its reduction-form product, which is in a cubic crystal structure having diffraction lines at lattice spacings (d) of at least 8.4, 6.8, 5.9 4.8, 4.2 and 3.4 in the X-ray powder diffraction. Such heteropoly-acids are useful as catalysts.