Fluid Cracking Catalyst (FCC) and three different modified bio-chars were tested for their thermal degradation capability of acetic acid in a custom-made continuous-flow reactor operated at 450 degrees C under nitrogen flow. The tested modified bio-chars were: switchgrass bio-char (BC), bio-char impregnated with nickel nitrate solution (BCNi), and bio-char deposited with iron oxide (BCFe). The modified bio-chars showed acetic acid degradation capability comparable to the FCC catalyst as quantified by total conversion. The total conversions were 5.55%, 17.33%, 15.21%, and 12.41% for the blank (no catalyst), modified bio-chars (BC and BCNi), and FCC catalyst, respectively while modified bio-char BCFe showed the highest conversion of 40.66%. (C) 2016 Elsevier Ltd. All rights reserved.