Gold supported iron oxide–hydroxide derived from iron ore tailings for CO oxidation

Iron ore tailing, a waste material of iron ore industry, has been used to prepare iron oxide–hydroxide support for anchoring nano-gold particles. FeOOH was prepared from iron chloride solution obtained from acid digestion of iron ore tailing. Precipitation deposition method was used to prepare Au supported FeOOH. The samples were characterized by XRD, TEM, TG-DTA and FTIR. The XRD studies have confirmed the FeOOH phase and the TEM studies reveal the anchoring of gold particles on FeOOH whose size is about 5 nm. FTIR spectra showed the vibration mode of metal–oxygen bond and the presence of hydroxyl group in FeOOH and Au/FeOOH. TG-DTA results confirmed dehydration of FeOOH and the process is retarded by the presence of Au particles. The catalytic conversion of carbon monoxide by Au/FeOOH was around 55% but the catalyst became inactive after pretreatment at 300 °C in presence of oxygen which led to agglomeration of Au particles and removal of hydroxyl groups from the surface of FeOOH.