Fabrication of hydrophilic special sandwich structure of PAN/GO/SiO2 electrospun membrane decorated with SiO2 nanoparticles for oil/water separation

In this paper, a special sandwich structure of the PAN/GO/SiO2 microfiltration membrane was developed using the electrospinning/electrospraying method for efficient oil/water separation. The results of morphological and structural studies confirmed that spraying SiO2 nanoparticles (NPs) to the outer surface of PAN/GO nanofibers (NFs) increased the surface roughness and decreased the water contact angle value, which is responsible for the improved hydrophilicity. Moreover, the addition of SiO2 NPs to the middle layer enhanced the porosity and the membrane flux up to 78 % and 423.7 ± 7.1 (L/m2.h), respectively. The values of oil/water rejections indicated the good performance of the PAN//GO-SiO2(1:1)//PAN-SiO2 membrane. Results supported that the presence of SiO2 NPs with a hydrophilic nature led to optimum oil/water separation with rejection over 98 %, obtained under the driving of gravity for free-surfactant Toluene emulsion, and above 97 % for the other types of oils (Pump oil and sunflower oil).