Investigating the effect of carbon nanotubes and graphene oxide on water/crude oil separation efficiency in polystyrene nanofiber membrane

In recent years, carbon-containing nanofibrous membranes have been used for oil separation purposes due to their superhydrophobicity, high specific area, high porosity, low basis weight, and selectivity. This work aims to study the effect of different carbon-based materials including multi-wall carbon nanotubes (MWCNT) and graphene oxide (GO) on the water/crude oil separation efficiency of electrospun polystyrene (PS) nanofibrous membrane. In the following, an experiment based on factors including the concentration of PS, the concentration of MWCNT, the concentration of GO, and the type of crude oil (heavy and light) which comes to a total sample of 32 is performed. After selecting the best combination of the factors, the optimum sample is chosen to be used as double and triple-layer membranes in the same condition as the main experiment. The results showed that the optimum membrane of 20 wt% of PS, 1.5 wt% of MWCNT, and 15 mL of either heavy or light oils can lead to about 90% separation efficacy. Furthermore, both doubled and tripled membranes showed approximately 99.99% separation efficacy. However, tripled layered membrane demonstrated lower flux (335.10 L/m2⁢h for heavy oil and 450.19 L/m^2⁢h for light oil) than doubled one (350.32 L/m²⁢h for heavy oil and 525.13 L/m^2⁢h for light oil) due to its higher thickness.