Electrospun silk nanofibers for numerous adsorption-desorption cycles on Reactive Black 5 and reuse dye for textile coloration

Abstract

Despite the fact that numerous effective adsorbents have been developed and the fact that adsorption is an appropriate technology for the removal of textile waste, cyclic adsorption-desorption and the reusability of collected waste dye have proven to be difficult to achieve thus far. Therefore, we report the fabrication of electrospun silk nanofibers (ESNFs) membranes for textile dye adsorption, desorption, and reusability. The surface morphology and chemical structure of ESNFs membranes were characterized using FE-SEM, FTIR and XPS techniques. We showed that ESNFs membranes can be efficient adsorbent for Reactive Black 5 (RB5) dye and 40 mg ESNFs have capacity to adsorb up to 98 % of RB5 (dye concentration 100 mg/L) in 5 mL volume of dye solution within 5 min at pH 5. Good physicochemical stability and physical attachment of RB5 on ESNFs membrane, enables a way for 20-time good cyclic adsorption-desorption. The experimental kinetic and isotherm data were well explained by pseudo-second order kinetic model and Langmuir adsorption isotherm model, respectively. Due to simple desorption achieved in alkaline DI water, we proposed a reusability of waste collected dye in textile coloration (cotton fabric coloration). As a result of these findings, we now know that ESNFS are an easy-to-use, cost-effective, resilient, and cyclic adsorbent that may serve as an alternative for various practical applications.