(749b) Anchoring of Iron Hydro(oxide) Particles On Activated Carbon for Removing Hexavalent Chromium From Aqueous Solutions

Adsorption processes are considered as a viable option for the removal of heavy metals from aqueous solutions. Metal oxide particles can be used for the adsorption of negatively-charged species such as hexavalent chromium but these particles cannot be packed in columns because of the high pressure and the possibility of losing these small particles in continuous operation. To overcome these shortcomings, in this research ferrous hydro(oxide) nanoparticles were anchored by forced hydrolysis at different conditions on commercial activated carbon for removing hexavalent chromium from aqueous solutions. Findings demonstrate that temperature, salt concentration as well as ageing time significantly affected the quantity of iron hydro(oxide) particles anchored to the porous activated carbon although surface area did not change notably after the forced hydrolysis process. Moreover iron-loaded activated carbon was capable of removing almost twice the quantity of hexavalent chromium per gram of adsorbent in comparison with the non-treated activated carbon. Finally, a high percentage of hexavalent chromium can be desorbed from iron-loaded activated carbon with alkaline solutions.

In conclusion, iron hydro(oxide) particles can be anchored by forced hydrolysis treatment in activated carbons increasing the removal efficiency of hexavalent chromium from aqueous solutions.