Adsorptive potential of sulfonated poly(glycidylmethacrylate)-grafted cellulose for separation of lysozyme from aqueous phase: Mass transfer analysis, kinetic and equilibrium profiles

. The operational lines along with the theoretical number of stages for the adsorption of LYZ onto PGMA-g-Cell-SO 3H. [Display omitted] ► Chemical modification of cellulosic materials, followed by functionalization, is a promising technique to improve the adsorption potential as well as to prevent the solubility in acidic and basic medium. ► A novel sorbent, Poly(glycidylmethacrylate)-grafted cellulose having sulfonate functional group (PGMA-g-Cell-SO 3H) was synthesized by graft copolymerization of glycidylmethacrylate (GMA) onto cellulose followed by the introduction of sulfonic acid. ► Adsorption characteristics of LYZ onto PGMA-g-Cell-SO 3H were investigated under different optimized conditions of pH, contact time, initial LYZ concentration, adsorbent dose and temperature. ► Regeneration experiments were tried for several cycles. ► The results of this study suggest that adsorbent exhibits significant potential as an adsorbent in the adsorption of LYZ from aqueous solutions. Lysozyme (LYZ) adsorption onto poly(glycidylmethacrylate)-grafted cellulose having sulfonate functional group (PGMA-g-Cell-SO 3H) was investigated. PGMA-g-Cell-SO 3H was prepared by graft copolymerization of glycidylmethacrylate (GMA) onto cellulose in the presence of ethyleneglycoldimethacrylate as cross linker using α,α′-azobisisobutyronitrile as initiator followed by the introduction of sulfonic acid groups through ring opening reaction of epoxide group in grafted GMA with sodium sulfite–isopropanol–water mixture. The adsorbent was characterized by means of FTIR, SEM, XRD and BET analysis. The maximum value of LYZ adsorption was found to be 74.93 and 96.21 mg/g for an initial concentration of 150 and 200 mg/L, respectively, at pH 6.0. The batch adsorption process followed pseudo-second-order kinetics and the equilibrium was achieved within 3 h. The kinetic data were also analyzed using external and intraparticle diffusion models. The intraparticle mass transfer diffusion model gave a better fit to the experimental data. Equilibrium isotherm data were well fitted with the Langmuir isotherm with maximum adsorption capacity of 141.67 mg/g at 30 °C. Thermodynamic study revealed an endothermic adsorption process. All of the adsorbed LYZ was eluted completely by 0.2 M CH 3COOH solution. Results obtained from repeated adsorption/desorption process showed that PGMA-g-Cell-SO 3H can be used for the separation of LYZ from aqueous solutions.