N.F.M. Salleh, A.A. Jalil, S. Triwahyono, J. Efendi, R.R. Mukti, B.H. Hameed
A new promising adsorbent, Ni supported on γ-Al 2 O 3 was prepared in a simple electrolysis system (Ni/Al 2 O 3 -E) in minutes and was compared with the sample prepared by a physical mixing method (Ni/Al 2 O 3 -PM). The adsorbents were characterized by XRD, TEM, FTIR, 27 Al MAS NMR, XPS, and VSM. The results showed that besides NiO nanoparticles, a NiAl 2 O 4 spinel was also formed in Ni/Al 2 O 3 -E during the electrolysis via the dealumination and isomorphous substitution of Ni 2+ ions. In contrast, only agglomerated NiO was found in the Ni/Al 2 O 3 -PM. Adsorption test on removal of Pd 2+ ions from aqueous solution showed that the Pd 2+ ions were exchanged with the hydrogen atoms of the surface-OH groups of both adsorbents. Significantly, the Ni/Al 2 O 3 -E demonstrated a higher adsorption towards Pd 2+ ions than Ni/Al 2 O 3 -PM due to its remarkably higher degree of magnetism, which came from the NiAl 2 O 4 . The use of 0.1 g L -1 Ni/Al 2 O 3 -E gave the maximum monolayer adsorption capacity (q m ) of 40.3 mg g -1 at 303 K and pH 5. The Ni/Al 2 O 3 -E showed high potential for simultaneous removal of various noble and transition metal ions and could be also used repetitively without affecting the high adsorptivity for Pd 2+ ions. This work may provide promising adsorbents for recovery of various metals as well as other materials for such related applications. © 2015 Elsevier B.V. All rights reserved.
Department of Chemical Engineering, Faculty of Chemical Engineering, Universiti Teknologi Malaysia, 81310 UTM Johor Bahru, Johor, Malaysia; Centre of Hydrogen Energy, Institute of Future Energy, Universiti Teknologi Malaysia, 81310 UTM Johor Bahru, Johor, Malaysia; Department of Chemistry, Faculty of Science, Universiti Teknologi Malaysia, 81310 UTM Johor Bahru, Johor, Malaysia; Department of Chemistry, Universitas Negeri Padang, Jl. Prof. Hamka Air Tawar, Padang, West-Sumatera, Indonesia; Division of Inorganic and Physical Chemistry, Faculty of Mathematics and Natural Science, Institut Teknologi Bandung, Jl Ganesha No 10, Bandung, 40132, Indonesia; School of Chemical Engineering, Engineering Campus, Universiti Sains Malaysia, Nibong Tebal, Penang, 14300, Malaysia
