A mat based on PVA doped with TiO2 nanoparticles for removal of methylene blue dye from aqueous solution and improving the carbon footprint

Abstract

Water supply is the great challenge for climate change and overpopulation. A Nanofiber mat consisting of Poly vinyl alcohol (PVA), nanoTiO_2, and citric acid (PTC) was prepared using an electrospinning technique at a constant flow rate (0.5 ml/h). The morphology of the mat was detected using (FESEM) technique and image J software; they show that the mat has a Nanofiber morphology with an average diameter of 170 nanometers. This mat was used to remove methylene blue (MB) from water in two ways, the adsorption process and by photodegradation using UV light. The kinetic study of the adsorption of methylene blue MB on a PTC mat was carried out. results show that the pseudo-second order is best to describe the adsorption, of MB and the Intra- particle diffusion is the rate determining step. Seven isotherm models; four of two-parameters and three of three-parameters were used to examine the adsorption experimental data by applying linear and non-linear regression method using six error functions. The results showed comparable data between linear and non-linear regression methods for two parameters isotherms, and the best isotherm fitting with the data were Freundlich and Temkin models. On the contrary, three parameters isotherms showed distracted data between linear and non-linear regression methods. In addition, the results appear that the best predictive error function was ꭓ².