Radiation crosslinked magnetized wax (PE/Fe3O4) nano composite for selective oil adsorption

•A microcrystalline polyethylene wax containing iron oxide magnetite (Fe3O4) nanoparticles were manufactured.•The magnetic moment of Fe3O4 in order to change orientation and crystallinity increases of LDPE wax pellets.•(LDPE/Fe3O4) wax irradiated by γ-rays at dose 50 kGy under ambient conditions.•Introducing 30% of Fe3O4 increasing the melting point of pellets from 107 °C to 111 °C.•Quickly absorb floating oils on the water surface, it was found that the amount of oil removal was 98% after 130 s.

Pellets of polyethylene wax are prepared from pellets of low density polyethylene (LDPE) by a sequence of radiolysis and thermolysis processes. The (LDPE) pellets are irradiated by gamma rays at a dose of 50 kGy in water and then thermally decomposed at 350 °C. To acquire magnetic property, the pellets of PE wax are composite with 30 wt% of (Fe3O4) nanoparticles by a molten process. The pellets of (PE/Fe3O4) wax are re-irradiated by γ-rays at a dose of 50kGy under ambient conditions. Effect of gamma radiation and the Fe3O4 content on the melting point (Tm) of PE wax was investigated by differential thermal analysis (DTA). The results shown the gamma radiation causing an increase in the melting point of the PE wax free Fe3O4 from 106 °C to 107 °C, while 30% of Fe3O4 increase the melting point from 107 °C to 111 °C. The transmission electron microscope (TEM) revealed that the Fe3O4 nanoparticles were relatively well dispersed in PE wax matrix with size ranged from 10 to 12 nm. The scanning electron microscopy (SEM) shows the rough surface with some cavity of the irradiated (PE/Fe3O4) wax. For this it could be used for oil/water separation. The crucial fuel oil produced from the automobile engine contaminated with water as an example. The magnetized wax can be used for crucial fuel oil /water separation, which can be collected by an external magnet to be reuse. It was found that the magnetic PE wax shows a good removal of oil with a total amount 98% after 130 s.