Thermodynamics and Kinetics study of Lead Ions Adsorption on Iraqi Bentonite

Abstract

Evaluation of adsorption parameters of Iraqi bentonite for lead ions (Pb2+) was investigated in a temperature range (10 – 50 oC) and pH values range (2-10). The method was based on the calculation of Langmuir adsorption maximum (b), and the bonding energy term (KL). The parameters were the outcome of well – established linear relationships of Ce/Q versus Ce (Ce, equilibrium concentration and Q, amount of lead adsorbed). The Q values increased with temperature and pH increasing. Kinetics study was conducted by using Lagergreen equation and a first order equation was obtained at time ranging from 5 mints to equilibrium time, and the rate constant of adsorption was calculated. The study included the adsorption of lead ions attached to EDTA as a complex (Pb – EDTA) on bentonite.