Adsorption of Pb(II) from aqueous solutions using corn straw

Large amounts of wastewater containing heavy metals are discharged from electroplating, metal finishing, textile, and other industrial plants, bringing health risks to humans and animals. There is, therefore, a growing concern to find low cost and effective ways to remove heavy metals from wastewater. In the present study, untreated corn straw was used as an adsorbent, and basic parameters for lead Pb(II) adsorption were studied. The Pb(II) adsorption was found to be dependent on contact time, pH, adsorbent dosage, initial concentration of Pb(II), and temperature. The kinetics were studied using pseudo-first order, pseudo-second order, Elovich, and Weber-Morris models, and the kinetic parameters were determined. The untreated corn straw particles showed the maximum adsorption capacity (15.0269mg/g) for Pb(II). The adsorption isotherms indicated that the heat of adsorption linearly increased as the thickness of the Pb(II) layer on the adsorbent gradually increased. The studies showed that corn straw can be used as a good adsorbent material for Pb(II) removal from aqueous solutions.