Magnetite-silica core–shell grafted myristic acid nanocomposites for oil adsorption from petroleum wastewater

Abstract

Removing oil content from this water is critical for meeting governmental discharge limitations and providing a large amount of clean water. In this study, a new magnetite-silica core/shell nanocomposite was synthesized and functionalized with myristic acid and designated by (Fe₃O₄/SiO₂@MA) used to remove oil from petroleum wastewater. Various analytical techniques characterize the prepared nanocomposite, such as XRD, FTIR, TEM, and SEM. The adsorption experiments were carried out in batch mode to determine the effect of the pH, amount of adsorbent, initial concentration of the emulsified oil, temperature, and contact time. The results indicate that the adequate conditions to adsorb emulsified oil onto (Fe₃O₄/SiO₂@MA) were at pH 10, at 60 °C, emulsified oil concentration of 0.5 g/L during one h of contact time. Finally, the results showed that 1 g of (Fe₃O₄/SiO₂ @ MA) can absorb 81.4% of emulsified oil. The Langmuir and Freundlich models were used to describe the adsorption isotherm equilibrium. The adsorption isotherm was best fitted well with the Langmuir model. The kinetic evaluations of oil removal by the Fe₃O₄/SiO₂@MA followed pseudo-second-order.

Graphical abstract

Keywords:

• Wastewater
• nanocomposites
• oxidation
• magnetic
• capacity
• adsorption