Microwave – Assisted production of hydrophilic carbon-based magnetic nanocomposites from saw-dust for elevating oil from oil field waste water

The current study aimed at developing new advanced, environmentally friendly and cost-effective materials in order to facilitate oil/water separation. In this study, novel synthesis of activated carbon was achieved from saw-dust which is considered as an environmentally hazardous waste. Moreover, it was further modified by the incorporation of magnetite nanoparticles. Moreover, hydrophilic nanomaterials i.e. silica and bismuth oxide nanoparticles, were added and the fabricated nanocomposites were referred to as MAC/SiO2 and MAC/Bi2O3. The prepared nanocomposites were synthesized via green microwave-assisted pyrolysis of saw-dust followed by incorporation of nanomaterials via co-precipitation method. Characterization of the prepared nano materials was achieved by using several analytical techniques including; FESEM, HR-TEM, DLS and Zeta potential, TGA, FTIR, and XRD. A column separator was designed for oil water recovery by the prepared nanocomposite materials. Different parameters which affect the oil-separation process were studied including; amount of nanocomposites, initial oil concentration, pH and water salinity. This was performed by the response surface methodology (RSM). An optimal design of experiment (ODOE) was employed to investigate the effect of the individual and the interaction between the studied parameters. It was designed at 95% confidence. Afterwards, the simulation of oil-recovery efficiency by nanocomposites were optimized and modulated under these operational parameters assisted by ANOVA analysis. The data were fitted with polynomial equation with R2 value of ≈0.99 and low error analysis was obtained between the experimental results and the predicted values. High oil recovery with oil separation rate was attained at optimum conditions even after 5 cycles and reached 99.4% for MAC/SiO2,93.9% for MAC and 90.6% for MAC/Bi2O3. •AC/magnetite/SiO2 and AC/magnetite/Bi2O3 were prepared using dip coating method.•Application of AC/magnetite/SiO2 in oil/water separation.•The amphoteric MAC/SiO2 has excellent affinity with oil-water separation.•MAC/SiO2 could be reused several times up to 5 times.