Optimization and design of a continuous biosorption process using brown algae and chitosan/PVA nano-fiber membrane for removal of nickel by a new biosorbent

In this study, nickel ions adsorption from zinc ingot factory wastewater by brown algae (Sargassum glaucescens) and chitosan/polyvinyl alcohol nano-fiber membrane at continuous system was studied. The continuous process included a biosorption reactor and fixed-bed reactor that were optimized by predicting two batch steps with response surface modeling, based on the Box-Behnken in the novel approach. Nano-biosorbent characterized by scanning electron microscopy, Brunauer-Emmett-Teller and Fourier transform infrared spectrometer analysis. Maximum biosorption in this continuous system was at pH 6, biosorbent doses 8 g L-1 S. glaucescens and 0.48 g L-1 nano-fiber. The study of the reaction rate showed kinetic data best fitted by pseudo-first-order model with R (2) > 0.95 than pseudo-second-order and intraparticle diffusion models. Biosorption equilibrium data were performed using Langmuir isotherm and Freundlich isotherm, Langmuir isotherm fit better with equilibrium data.