Crosslinked Egg White as Eco-Friendly, Reusable, and Cost-Effective Biosorbent for Rapid Removal of Indigo Carmine

Abstract

In the present study, crosslinked egg white is used as a low-cost biosorbent for removal of a toxic dye, indigo carmine. The biosorbent preparation is easy and only N, N'-methylenebisi(acrylamide) is added for crosslinking. The characterization of the prepared material is done with scanning electron microscopy and IR spectroscopy. The surface charge is determined with point of zero charge method. The prepared biosorbent is used for removal of indigo carmine. The experimental parameters i(e. g., pH of solution, initial dye concentration, time) are optimized to achieve quantitative removal. The biosorption data of indigo carmine on crosslinked egg white is fitted with the Langmuir model with a Qmax value of 67.56mg g(-1). The kinetic data are treated with pseudo-first-and second-order models. The second-order model best explains the kinetic behavior of the process. The quantitative extraction of indigo carmine is achieved for 25 mgg(-1) of IC within 30 min at pH 2. The crosslinked egg white can be used several times after regeneration.