Adsorption of Divalent Cobalt from Aqueous Solution onto Chitosan–Coated Perlite Beads as Biosorbent

Abstract

Chitosan coated perlite beads are prepared by drop‐wise addition of a liquid slurry containing chitosan and perlite to an alkaline bath. The resulting beads are characterized using FTIR, SEM, EDXRF, and Surface area analysis and the chitosan content of the beads is 23% as determined by a pyrolysis method. Adsorption of Co (II) metal ions from aqueous solution on chitosan coated perlite beads is studied under both equilibrium and dynamic conditions. In the present investigation, a first order reversible rate equation is used to understand the kinetics of metal removal and to calculate the rate constants at different initial concentrations. The equilibrium characteristics of metal ion on newly developed biosorbent are studied and the experimental adsorption data are well fitted to Freundlich and Langmuir adsorption isotherm models and the model parameters are evaluated. The effect of pH, agitation time, concentration of adsorbate, and amount of adsorbent on the extent of the adsorption are investigated. The sorbent loaded with metal is regenerated with 0.10 mol dm−3 sodium hydroxide solution. The adsorption desorption cycles indicated that the chitosan coated perlite could be regenerated and reused to remove Co (II) from waste water.