Kinetics of the recovery of nickel from depleted catalysts used in the reforming of methane

Thermogravimetric (TG) measurements were carried out in a mixed flux of Cl2 and Ar in non-isothermal conditions up to 950 °C. The beginning of the reaction in the first mixture was detected at 384 °C and close to 653 °C the volatilization of NiCl2 started. Besides, NiO reacts at 473 °C and NiCl2 volatilizes at 577 °C. There is no reaction with Cl2 and no phase transition of γ-Al2O3. In order to find out the reaction rates, mass changes of the reactants were measured under the same gaseous flow and in isothermal conditions.