The solubility of carbon dioxide (CO2) in a new low-viscosity and non-fluorinated ionic liquid, 1-hexyl-3-methylimidazolium tetracyanoborate ([hmim][TCB]), has been studied experimentally using a synthetic method. Bubble point pressures (up to 12.34 MPa) of the system CO2 + [hmim][TCB] are reported for CO2 concentrations ranging from 10.09 to 70.16 mol% and within a temperature range of 283.56-364.04 K. The experimental values of the density, the viscosity and the surface tension of [hmim][TCB] are also reported. The results obtained are compared to available CO2 solubility data and physicochemical properties of other 1-hexyl-3-methylimidazolium based ionic liquids in order to study the effect of the type of anion. It is found that [hmim][TCB] shows higher CO2 absorptive capacity (higher solubility) as well as faster CO2 mass transfer kinetics (lower viscosity), which makes this ionic liquid an attractive solvent for gas separation processes. (C) 2012 Elsevier B.V. All rights reserved.