Enhanced efficiency of polyamide membranes by incorporating cyclodextrin-graphene oxide for water purification

Abstract

Climate change, growing population, and industrial activities are exerting tremendous pressure on water quantity and quality. Pollution of water resources from high concentrations of organic and inorganic compounds makes the available water unsuitable for use by the populace and industry. An efficient water purification technique can simultaneously address many classes of pollutants. Here, a novel polymer-supported thin film nanocomposite membrane was synthesized, and its permeability and rejection of organic and inorganic contaminants over time were investigated. The fabricated multilayer membrane was characterized using field emission scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDX), atomic force microscopy (AFM), Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD) to understand the variation in the surface structural morphologies, roughness profiles, polymer and molecules interactions, mineralogical and elemental compositions of the synthesized composite membrane before and after its use for the treatment. The flux and separation tests were conducted to evaluate the permeability performance and separation capacity of the prepared composite membrane for the removal of salts, heavy metals, and organic contaminants. The results show the highest membrane flux of 100 L m-2 h-1 at 15 min, which later declined and stabilized 40 L m-2 h-1 after 4 h. Almost 100% rejection was attained to remove 1000 mg/L, 100 mg/L, and 250 mg/L of salts, heavy metals, and organic contaminants, respectively for over 5 h. These impressive and stable permeability and separation performance make the prepared GO-incorporated nanocomposite membrane as a promising membrane for the filtration and purification of wastewater and seawater.