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

FABIOLA JULIETA ALVAREZ; DANIEL MIGUEL PASQUEVICH; ANA ESTER BOHÉ

International Journal of Hydrogen Energy

John Sheffield-ELSEVIER

Año: 2008 vol. 33 p. 3438 - 3441

0360-3199

In the current work the separation of nickel from alumina is proposed when it is present in the following mixtures: 10 wt% Ni + 90 wt% Al2O3, 12 wt% NiO + 88 wt% Al2O3, making use of a tubular reactor, with a flow of 2 l/h of gaseous chlorine and from 500º to 800 ºC. The final products of the reaction, extracted from the hottest zones of the reactor where characterized as NiCl2 y NiCl2.6H2O, and the predominating phase of alumina condensed with NiCl2 up to 700ºC was ã.Al2O3. Thermogravimetric measurements (TG) of were carried out in a mixed flux of Cl2 and Ar in non-isothermal conditions up to 950ºC. The beginning of the reaction in the first mixture was detected at 384ºC and close to 653ºC the volatilization of NiCl2 started. Besides, NiO reacts at 473ºC and NiCl2 volatilizes at 577ºC. There is no reaction with Cl2 and no phase transition of ã.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.