Cation removal behaviour by cross-linked sodium alginate-PVA beads: characterisation, kinetics and equilibrium studies

Abstract

Novel adsorbent materials were prepared from sodium alginate and polyvinyl alcohol (AL-PVA) in 5 different ratios to evaluate their adsorption capacities for Pb(II), Cu(II) and Zn(II) in a multicompo-nent solution of 10 mg/L of each metal, then they were tested with wastewater from a glass industry to remove these heavy metals. The adsorption tests with the materials of different AL-PVA ratios showed that the most efficient material was the one with the ratio 50/50, this composite was characterized by SEM and FTIR spectra before and after the adsorption process; the zero-point charge, swelling kinetics and acid resistance tests were determined. The experimental multicomponent adsorption kinetics data fitted best the pseudo-first-order model according to the R2 values and the similar-ity between the experimental adsorption capacity and the calculated one, the adsorption isotherm data of Pb(II) fitted best to the linear model and those of Cu(II) and Zn(II) to the Langmuir model. The adsorbent material shows a high potential for the removal of Pb(II), Cu(II) and Zn(II).