Dye removal membrane from electrospun nanofibers of blended polybutylenesuccinate and sulphonated expanded polystyrene waste

Abstract

Polystyrene (PS) is a thermoplastic polymer used in food packaging and the manufacture of trays and cups, among other applications. In this work, the preparation of a membrane by electrospinning blended sulphonated expanded PS waste and polybutylenesuccinate (PBS) is described. The fiber quality is controlled by selecting the right polymers’ ratios and solvents. Investigation of the structure of the produced membranes by Fourier transform infrared spectroscopy-attenuated total reflectance confirmed the successful sulphonation of expanded PS and the appearance of characteristic (PBS) bands in the prepared blends. Morphology study of the electrospun membranes using a scanning electron microscope revealed that the quality of the fibers is improved significantly by increasing the amount of PBS in the blend solution. Moreover, continuous and more homogenous fibers are produced by increasing the ratio of PBS to 2%. The efficiency of the prepared membranes in dye removal was tested using methylene blue. The effects of different parameters such as, pH, contact time, temperature, and dye concentration have been studied. Also, kinetic and adsorption isotherm models as well as the durability of the prepared membranes were investigated. The membrane prepared from PSS/1% PBS demonstrated the highest dye uptake (846 mol) with good regeneration efficiency. The adsorption process was found to be endothermic and fits the Freundlich isotherm and pseudo-second-order kinetic model. The values of activation energy for the adsorption process are 36.98, 30.70, and 43.40 kJ/mol over PSS, PSS/1% PBS and PSS/2% PBS, respectively.