Ionic liquid functionalized egg residues as efficient biosorbents for anionic orange G dye

Abstract

ABSTRACT Ionic liquid functionalised egg residues were tested for their biosorption ability towards water soluble anionic ‘orange G’ dye. Egg residues after ionic liquid treatment were characterised via FTIR, SEM and TGA. Adsorption process was optimised by evaluating different experimental parameters including effect of adsorbent dose, contact time, agitation speed, temperature and pH. Modified egg shell membrane (MESM) exhibited higher efficiency for orange G dye adsorption followed by unmodified egg shell membrane (ESM) and powdered egg shell (PES). Equilibrium states were achieved in 1 hour for the different studied initial dye concentrations at acidic pH, 120 rpm and 30°C. Under optimum conditions >95% dye is removed with 27 mg/g adsorption capacity of MESM for 80 ppm dye solution. Study was further extended to find the best-fitted kinetic and isothermal model. It was found that the process follows pseudo-second-order kinetics and Langmuir isothermal model. Adsorbent was regenerated and reused without significant loss of efficiency. This research work presented that ionic liquid modified egg shell membrane is highly efficient with regard to its ecological perspective and cost effectiveness for the removal of toxic dye from wastewater.