Adsorptive mixed matrix membrane incorporating graphene oxide-manganese ferrite (GMF) hybrid nanomaterial for efficient As(V) ions removal

Abstract

Millions of people in the world are exposed to arsenic-contaminated drinking water, causing them to have serious health problems. Compared to the conventional treatment method that uses nanoparticles to eliminate arsenic from water, emerging membrane technology, i.e., adsorptive mixed matrix membrane (MMM) offers unique features including one-step treatment, high reusability and effective even for extremely low concentration of contaminant. In the present study, hybrid nanomaterial namely graphene oxide-manganese ferrite (GMF) was self-synthesized followed by incorporation into polymeric membrane matrix to produce MMM for arsenate (As(V)) ion removal via adsorption-filtration method. The synthesized nanomaterial was characterized using Brunauer, Emmett and Teller (BET) analyzer, Fourier transform Infrared (FTIR) spectroscope, X-ray diffraction (XRD) analyser and transmission electron microscope (TEM), while the developed MMMs were characterized using scanning electron microscope (SEM) equipped with energy dispersive X-ray (EDX) spectroscope and contact angle goniometer before being used in adsorption-filtration process. The maximum adsorption capacity (qmax), adsorption isotherm and kinetic properties of the MMMs were determined by batch adsorption studies, while the adsorption-filtration experiment was conducted to evaluate the MMMs ability with respect to As(V) removal in cross-flow system and regeneration capability. The best performing MMM could achieve maximum adsorption capacity of 75.5 mg/g at pH 4 and uphold permeates level below the drinking water standard for up to 4 h in a cross-flow filtration process. These findings indicated that the newly developed MMMs are potential to be used as single-treatment method for As(V) ion removal.