Adsorptive removal of oil spill from sea water surface using magnetic wood sawdust as a novel nano-composite synthesized via microwave approach.

Water pollution by oil is a serious environmental problem. Developing new generation of benign adsorbents satisfying several criteria required for real practical application is of great need. This work introduces an effort in this direction, by utilizing a facile synthesis of wood sawdust coated magnetite nanoparticles functionalized stearic acid (WSD@Fe3O4NPs/SA) as a novel nano composite along with its precursor WSD@Fe3O4NPs. SA was covalently bonded to the precursor by amide bond formation via the interaction with the silylating agent 3-aminopropyltrimethoxysilane (3-APTS). This mode of binding is more stronger than the conventional ester bond. Fourier transform infrared (FT-IR), X- ray powder diffraction (XRD), Scanning electron microscope (SEM) and Transmittance electron microscope (TEM) were employed for characterization and follow up the synthesis process. Application of the newly synthesized magnetic nano composite adsorbent under optimized parameters of contact time (min) and composite dosage (g) reveal high removal capacity values (g/g) evaluated to be 28.32 g/g, 5 min and 0.1 g for used motor oil removal and 41.22 g/g, 10 min and 0.1 g for crude oil. The high removal efficiency exhibited by WSD@Fe3O4NPs/SA was mainly argued to the long hydrocarbon chain of SA moiety and additional ـــ (CH2)3 ـــ groups incorporated 3-ATPS. Moreover, Analysis of the oil adsorption experimental equilibrium data were well fitted with Freundlish model with correlation coefficients r2 = 0.9788 and 0.9896 for used motor oil and crude oil, respectively. The kinetic data were correlated using two kinetic models and the results were in harmony with pseudo-second order. © Springer Nature Switzerland AG 2020.