LOW-TEMPERATURE SINTERING STUDIES OF AMMONIUM MOLYBDATE, NICKEL-HYDROXIDE AND NICKEL MOLYBDATE

The thermal decomposition of ammonium molybdate, nickel hydroxide and MoO3-NiO 50 mole % mixture were studied by means of TG and DTG non-iso thermally, in a dynamic atmosphere of N2. The activation energy of the thermal process of such samples, also, were evaluated using Maple's t heory, in isothermal condition. The variation of S(BET) with time, dur ing heating ammonium molybdate, nickel hydroxide and MoO3-NiO 50 mole % mixture at different temperatures, in the range 200 - 400-degrees-C, was monitored, and the activation energy for the sintering process of each compound were calculated from the Arrhenius plot. The final prod ucts of heating each sample at the sintering temperatures after 6 h, w ere characterized by IR and XRD analyses. MoO3 was formed clearly at 3 50-degrees-C, while Ni forms a mixture of nickel(II) and -(III) oxides at the same temperature. NiMoO4 was produced, also, at 350-degrees-C in MoO3-NiO 50 mole % mixture sample.