Waste Engine Oil Sorption Capacity of Calcium Oxide Nanoparticle Synthesized Biologically with Eugenia Uniflora Leaf Extract

Biomolecules present in plant extracts can be used as capping and stabilizing agents which reduce metal ions or metal oxide ions to metal nanoparticles in a single-step green synthesis process. In this study, calcium oxide nanoparticle was synthesized using Eugenia uniflora leaf extract in order to ascertain its oil sorption capacity. The characterization of the calcium oxide nanoparticle through UV-vis spectroscopy revealed that maximum absorption was obtained at 207nm indicating surface plasmon absorption of calcium oxide nanoparticle. FTIR results of the Eugenia uniflora leaf extract before and after the synthesis of the calcium oxide nanoparticle indicated the absence of the O-H functional group of alcohol with peak at 3306.1 cm-1 and C-C functional group of alkane with peak at 1449.9 cm-1 indicating their responsibility for the reduction and capping of the synthesized calcium oxide nanoparticle. The morphology of the cacium oxide nanoparticle indicated no definite shape with smooth surface on magnification. The XRD pattern showed that the calcium oxide nanoparticle formed are crystalline in nature with average crystallite size of 3.25 to 4.76 nm. Effect of contact time on the oil sorption capacity of calcium oxide nanoparticle revealed highest sorption capacity at a shorter time (20 min). Kinetically, oil sorption capacity of CaO nanoparticle fitted the Pseudo-second-order model with R2 close to unity (i.e. 0.996). Mechanism of sorption is by chemisorption. Therefore oil sorption capacity of calcium oxide nanoparticle proved to be effective especially at low contact time can be used to clean oil polluted water.