Use of metallic iron for decontamination of solution containing Ni[II]-citrate

The use of carbon iron and the mechanical retread of iron surface enables us to remove both Ni(II ) and citrate from solutions containing the Ni(II )–citrate complex. The duration of decontamination and the consumption of Fe and acid depend on the complex concentration, pH, load and the presence of background electrolytes. The observed pseudo first order rate constants for citrate removal using carbon steel plates were kobs = 0.42; 0.082 and 0.068 at load 200; 80 and 20 g·l⁻¹, respectively. Chemical analysis, FT-IR and XRD investigations have shown that the precipitate formed contains mainly iron oxides, which exceed the citrate content in the precipitate several times.