Waste tyre rubber-magnetic nanoparticle composites as sorbents for oil removal from water

Abstract

Increases of waste tyre rubber (WTR) and there is not suitable disposal method for this waste. Several tons of WTR degrade slowly. For another environmental issue, oil spill is a worldwide problem. This work used composites between WTR and magnetic nanoparticles (MNPs) as sorbents to remove oil on water surface for easy disposal of sorbent out of water by mean of magnetic separation. The MNPs were synthesized by thermal decomposition of iron-oleate complex in order to control the sizes of MNPs. The WTR/MNPs composites were synthesized in different solvents including n-hexane, ethyl acetate, toluene, chloroform, benzene and acetone. Effects of reaction times and concentrations of MNPs in solvent on the properties of the composites were studied. Fourier transforms infrared spectrometer (FT-IR), Scanning electron microscope (SEM) and thermogravimetric analysis (TGA) were used for characterization. It was found that chloroform is the best solvent for incorporating MNPs into WTR at the concentrations of MNPs of 0.04-0.06 g/mL, resulting in the composites with 28.10% w/w of MNPs. The composites prepared using chloroform had highest capacity for diesel sorption at 2.14 ± 0.05 g·g⁻¹, while the composites using toluene in the preparation exhibited highest capacity for gasoline sorption at 2.02±0.08 g·g⁻¹. Both composites were efficiently removed after used by magnetic separation.