Nickel (II) Based Metal-Organic Framework Consolidated on Nanofibers Modified Track-Etched Membrane for Dye Removal

Abstract

Metal-organic frameworks (MOFs) are promising adsorption agents with many potential applications. However, most experiments exploring the potential applications of MOFs have used powders, which limits the range of possible applications. To solve this problem, an approach to design hybrid membrane (HM) based on tracketched membrane, electrospun nanofibers and MOF based on L-tryptophan, 1,2-bis(4-pyridyl)ethylene and Ni (II) (Ni-MOF) was proposed in the current paper. An investigation of Ni-MOF morphology on hydrophilic chitosan and hydrophobic polyvinylidene fluoride nanofibers showed that the Ni-MOF tends to form superstructures — spherical conglomerates consisting of flaky crystallites on both types of nanofibers. The HMs and Ni-MOF powder were characterized by SEM and PXRD. The adsorption properties of the Ni-MOF powder towards model anionic methyl orange (MO) and cationic rhodamine B (Rh B) including kinetics and isotherm were studied. An investigation of dyes removal by HMs in dead-end filtration mode indicates the effectiveness of MO and Rh B adsorption as high as ~97 % (~380 μg/cm2) and ~9 % (~37 μg/cm2), respectively. The possibility of regeneration was also investigated. Thus, the HMs may find a potential application for advanced wastewater treatment processes to provide removal of MO in microfiltration mode.