Fluffy-like amphiphilic graphene oxide (f-GO) and its effects on improving the antifouling of PAN-based composite membranes

Membrane fouling remains a significant restriction for the long-time operation. In this paper, fluffy-like amphiphilic graphene oxide (f-GO) was prepared by simple grafting silane coupling agent (KH-570) onto the graphene oxide matrix, and thus featured with good dispersion behavior in organic solution. The f-GO was further incorporated into the PAN-based (poly(acrylonitrile-methyl acrylate), P(AN-MA)) copolymer during the phase inversion process. Compared with the P(AN-MA) membrane, the resistance of the f-GO/P(AN-MA) composite membrane reduced from 4.49 × 10−12 m−1 to 1.78 × 10−12 m−1. The pure water flux increased from 200 to 326 L/m2h, while the water contact angle declined from 92.8° to 68.3°. It is worthy to note that the fouling mode changed from irreversible fouling to reversible fouling, with the total fouling rate showing a half decay. The fouling recovery rate reached 98.16% and the BSA rejection rate increased from 70.59% to 99.33% as 0.5 wt% f-GO was incorporated. The f-GO is easily scaled up and can be widely applied in other polymer matrices, showing potential application prospects in the membrane separation and purification area. The f-GO/P(AN-MA) composite membranes with excellent water flux, BSA rejection and FRR, are candidates for further employment in wastewater purification applications.