Greater concentration showed enhanced adsorption in all three
cases. High surface area and strong adsorption properties of the
coated graphenic layers generate this effect. Additively, oxygenated
carbon in CeO, formed due to presence of oxygen functionality,
facilitates adsorption. These adsorption experiments do not require
external energy sources as in photocatalysis. Regeneration and
reuse of adsorbent is possible by washing it with acetone
(Sreeprasad et al., 2013). River sand as substrate stabilizes the
graphenic layers hence making this process feasible for flowing
water conditions also.