The supported co-catalyst (Co, Ni)3O4/Al2O3 was prepared via co-precipitation method. Two sets
of these materials were prepared by calcination at two temperatures 500, and 600oC. Crystal structure of
the prepared materials was investigated using powder X-rays diffraction (PXRD), and specific surface area
(BET). The adsorption ability of the prepared catalyst (Co, Ni)3O4/Al2O3 was investigated by adsorption of
Bismarck brown G dye (BBG) from simulated industrial wastewaters. Equilibrium adsorption isotherms
and kinetics studies were investigated. The experimental data were analyzed according to Freundlich and
Langmuir models of adsorption. The adsorption isotherms data were fitted well to Langmuir isotherm and
the kinetic data were fitted very well with the pseudo-second-order kinetic model.