It has been shown that coprecipitation of Ni, Mo, and Al salts in an alkaline medium with subsequent heat treatment will yield an amorphous nickel aluminomolybdate with the composition Ni left bracket Al//xMoO//4// plus //1//. //5//x right bracket , which, when heated to 973 K, crystallizes into a phase that is isostructural with beta -NiMoO//4 and is stable after cooling. In an acidic medium, a nickel heteropolymolybdate is obtained with the composition Ni left bracket AlMo//6O//2//4H//7 right bracket ; this breaks down with the segregation of NiMoO//4, Al//2(MoO//4)//3, and MoO//3 at temperatures greater than equivalent to 773 K. The double molybdate of Ni and Al that is formed upon fusion of the components breaks down upon cooling below 1178 K, with the segregation of alpha -NiMoO//4, MoO//3, and Al//2(MoO//4)//3.
|Number of pages||10|
|Journal||Kinetics and Catalysis|
|Issue number||4 pt 2|
|State||Published - 1 Jul 1986|