Abstract

ROJAS-VARGAS, Armando et al. Remoción de níquel del sistema Ni(II)-NH3-CO2-SO2-H2O por electrocoagulación a escala de banco. Parte I. RTQ [online]. 2022, vol.42, n.1, pp. 114-130.  Epub Apr 30, 2022. ISSN 2224-6185.

The nickel removal from the Ni(II)-NH3-CO2-SO2-H2O system was studied by bench-scale electrocoagulation in a stirred cylindrical reactor, with a useful capacity of 25 L and two pairs of Al/Al electrodes. Effluent liquor from the distillation process of the nickel-producer plant in Punta Gorda, Cuba, and synthetic liquor prepared in the laboratory was used. The operating parameters were: pH 8,6, density of current 8,3 mA/cm2, 40 min of electrolysis, 60 ºC and initial concentration of dissolved nickel between 300 and 652 mg/L. An average removal efficiency of 99,67 (+/-0,06) % was obtained for the effluent liquor, resulting a maximum equilibrium concentration of 7 mg/L. The analysis of the reaction kinetics suggests that the removal is determined by the simultaneous contribution of the resistance of the mechanisms: nucleation, external diffusion, the chemical reaction and a possible autocatalytic effect by the Roginskii-Shultz equation.

Keywords : kinetic; electrocoagulation; nickel.