• adsorbent;
  • nickel;
  • low grade;
  • nickeliferous laterite;
  • hydrometallurgical extraction


A novel silica-based iminodiacetic acid functionalized adsorbent was fabricated and then used to nickel hydrometallurgical extraction for low-grade nickeliferous laterites. The surface morphology of the adsorbent was characterized by scanning electron microscopy. The adsorption experiment indicated a maximum nickel load capacity of about 0.45 mmol/g. Analysis of adsorption thermodynamic and kinetics revealed a spontaneous adsorption process driven by entropy increase, and limited by film diffusion. Semi-industrial scale column experiments revealed that the Ni2+ in the acidic leach liquor of low-grade nickeliferous laterites may be efficiently extracted by the iminodiacetic acid functionalized adsorbent, if the Fe3+ ions existing in the acidic leach liquor were previously reduced to be Fe2+ by sodium sulfite. This environmentally safe adsorbent may supplant the traditional solvent extraction process for low-grade nickeliferous laterites. © 2012 American Institute of Chemical Engineers AIChE J, 2012