Tungsten compound
1.A new type of polymetalatosilicate which contains three different metals-tungsten,molybdenum and vanadium-has been prepared. The compound β-Na9 [HSiW9O34 ]·23H2O which has vacant addend sites was first prepared by the reaction of Na2WO4·2H2O and Na2SiO3·9H2O. Then appropriate amounts of molybdate and vanadate were added to form products of precise Keggin structure.
