Separation of Ni and Co by D2EHPA in the Presence of Citrate Ion

• Published in: Metallurgical and materials transactions. B, Process metallurgy and materials processing science Process metallurgy and materials processing science, 2017-10, Vol.48 (5), p.2751-2758
• Main Authors: Nadimi, Hamed, Haghshenas Fatmehsari, Davoud, Firoozi, Sadegh
• Format: Article
• Language: English
• Subjects: Characterization and Evaluation of Materials; Chemistry and Materials Science; Cobalt; Coordination compounds; Economic conditions; Electronic waste; Extraction; Fourier transforms; Infrared spectroscopy; Ions; Materials recovery; Materials Science; Metallic Materials; Metallurgy; Nanotechnology; Nickel; Separation; Structural Materials; Surfaces and Interfaces; Thin Films
• ISSN: 1073-5615; 1543-1916
• DOI: 10.1007/s11663-017-1008-7

Recycling processes for the recovery of metallic content from the electronic wastes are environmentally friendly and economical. This paper reports a method for the recovery and separation of Ni and Co from the sulfate solution by the use of D2EHPA. In this regard, the influence of citrate ion, as a carboxylate ligand, was examined in the separation conditions of Ni and Co via D2EHPA (a poor selective extractant for Ni and Co separation). It was found that the Δ pH 0.5 Ni-Co (the difference between pH values corresponding to 50 pct extraction of metallic ion) increases to 1.5 at the citrate concentration of 0.05 M; this Δ pH 0.5 Ni-Co value is much higher than that obtained in the absence of citrate ion (0.1). Fourier Transform Infrared Spectroscopy (FT-IR) indicated that the citrate ion is co-absorbed during the metallic ions absorption by D2EHPA meaning that the metal–organic complexes contain Co/Ni and citrate ion. Also, the stoichiometric coefficients of the Ni and Co extraction reaction were proposed by applying the slope analysis method.