Abstract

Modified rice hulls system for removing Pb (II) from aqueous solutions has been investigated. Rice hulls are agricultural waste product. The experimental condition was the modification of the rice hulls (sorbent) with different concentrations of hydrogen peroxide solution. The experimental results were fitted to the Langmuir and Freundlich isotherms to obtain the characteristic parameters of each model. The Langmuir isotherm was found to well represent the results. The maximum sorption capacities of various concentrations of hydrogen peroxide modified rice hulls were 2.57, 3.15, 5.15, 8.57, 10.97 and 11.88 mg/g for 0.1, 0.3, 0.6, 0.9, 1.2 and 1.5 M hydrogen peroxide solution respectively.It was noted that increasing the concentration for modification resulted in a higher metal uptake per unit weight of the modified rice hulls.

Key words: Modified, Langmuir, Freundlich, hydrogen peroxide, rice hulls, lead.