Highly stable functionalized PAN/Zr Nanofibrous mats for removal of Ultra low Concentrations of Hg (II)

Abstract

Abstract Nanofibrous mats of polyacrylonitrile loaded with zirconia (PAN/Zr) have been fabricated and reported for the first time for effective removal of Hg (II) from water. The formation, morphology and adsorption characteristics of the composite nanofibrous mats were determined using scanning electron microscopy, Fourier transform infrared spectroscopy, x-ray diffraction and x-ray photoelectron spectroscopy. The thermal behavior of the prepared nanofibrous mat was studied using thermogravimetric analysis (TGA) and differential scanning calorimetry. The adsorption behavior of the nanofibers was studied as a function of time, pH, dose and concentration of the Hg solution. The Langmuir isotherm of the developed material indicates that it is very effective at removing low concentrations of Hg (even <50 ppb) in water. Kinetic data were fitted to first- and second-order kinetics, and the material was successfully regenerated by an acid solution and reused three times while retaining 80% removal efficiency for Hg. As the PAN/Zr/composite nanofibers are chemically and thermally stable, they can be easily regenerated and reused for effective removal of Hg(II), as per WHO/Environmental Protection Agency requirements.