The sorption experiments for the three single-component systems were carried out on a shaker using capped 125 ml Erlenmeyer conical bottles. In the sorption isotherm tests 0.5 g of peat was thoroughly mixed with the metal ion solution (125 ml). The concentration ranges and system studied are shown in Table 2. After shaking the bottles for 3 h, the reaction mixtures were filtered (Whatman No. 1) and the three filtrates were analysed for the concentration of copper(II), lead(II) and nickel(II), using inductively coupled plasma atomic emission spectroscopy (ICP-AES). The sample bottles were shaken in a thermostatically controlled shaking water bath at 2518C. The Analytical procedures and methods were carried out according to EPA standard methods for metal ion analysis. Previous work (Allen, 1987; Ho et al., 1994, 1995) demonstrated that under the experimental conditions used, equilibrium was reached in 2 h. The solution pH values of the initial and final solutions were measured. Initial pH values were 4.500.10 and final pH values showed some variation with initial solution concentration. The values are given in Table 3