Novel glycine-functionalized magnetic nanoparticles entrapped calcium alginate beads for effective removal of lead

Abstract

The magnetic Fe3O4 nanoparticles were functionalized with glycine at pH6. The glycine functionalized magnetic nanoparticles (GFMNPS) were then entrapped into alginate polymer as beads and used as adsorbent for the removal of Pb(II) ions. The developed adsorbents were characterized by Fourier transform infrared spectroscopy, vibrating sample magnetometer and scanning electron microscopic analysis. The surface of beads contain amino and carboxylate groups which make them effective adsorbents for the removal of Pb(II) ions. The adsorption of Pb(II) ions from aqueous solution was found to be highly pH dependent. 92.8% Pb(II) was removed just in 10min. The kinetic data fitted well with pseudo second order model and the equilibrium was reached in 100min with 99.8% removal of Pb(II) ions from aqueous solution. The adsorption isotherm strictly followed Langmuir model with the maximum adsorption capacity of 555.5mg/g of the adsorbent. The thermodynamic study confirmed that the adsorption was spontaneous and endothermic in nature. The adsorbent could be regenerated four times simply by 0.2M HNO3 retaining 90% of the adsorption capacity. The synthesized adsorbent was found to be eco-friendly, cost-effective, efficient and superior over other polymer based adsorbents for removal of Pb(II) ions from aqueous solution.