High-performance reverse osmosis nanocomposite membranes containing the mixture of carbon nanotubes and graphene oxides

Polyamide reverse osmosis membranes containing carbon nanotubes with acidic groups (CNTa), graphene oxide (GO), and both CNTa and GO (CNTa-GO) were prepared by the interfacial polymerization of trimesoyl chloride solutions in hexane and m-phenylenediamine aqueous solutions containing carbon nanomaterials. All of the polyamide membranes containing the carbon nanomaterials showed considerably improved membrane performances, such as water flux, chlorine resistance, long-term durability, and mechanical properties, compared to the polyamide membrane without any of the carbon nanomaterials due to the advantageous properties of the CNT and GO as the filler materials. The largest improvement of membrane performances was observed in the polyamide membrane with CNTa-GO (the mixture of CNTa and GO). CNTa-GO can be more well-dispersed in the aqueous solution than the one-component carbon nanomaterials, such as CNTa and GO, due to the surfactant effects of GO, and then, the polyamide membrane with CNTa-GO can contain the largest amount of the carbon materials among the membranes and show the best membrane performances.