Keywords: zinc removal, sequential bed adsorption column, low-cost adsorbents, Langmuir isotherm, intraparticle diffusion, aqueous solutions, Oryza sativa, rice husks
Removal of Zn(II) ions from aqueous solution using rice (Oryza sativa) husk in a sequential bed adsorption column
Batch studies carried out at varying pH, metal concentrations, temperature, particle size, and contact times indicate 75% removal of Zn2+, at pH 8 in 2.5 h for the concentration range 30-300 mgL−1. The sorption data fits to both the Freundlich and Langmuir isotherm models. Intraparticle diffusion constant and ΔG have been calculated. Column studies using sequential bed column at varying particle sizes and flow rates show that this column is relatively more effective, as compared to the vertical column under similar conditions, in terms of efficiency, cost and handling and can be used in small scale industries.