Fe-based alkylimidazolium halide ionic liquids ([bmim]center dot FeXCl3, X = Cl and Br) were prepared by a two-step reaction. And then the ionic liquids were characterized by infrared spectroscopy, Raman spectroscopy, nuclear magnetic resonance, thermogravimetric analysis and viscosity measurements. The Hg-0 removal performance of the ionic liquid was also investigated in a gas/liquid scrubber using simulated flue gas. It was found that the ionic liquid possessed low viscosity and high thermal stability, and could be used as an absorbent for Hg-0 removal from the flue gas. The ionic liquid showed high Hg-0 removal efficiency (up to 98%) in the temperature range of 60-100 degrees C. The Hg-0 removal mechanism involved with Hg-0 oxidation by the anion of ionic liquid and the regeneration of the anion. (C) 2014 Elsevier B.V. All rights reserved.