Removal of heavy metal by using biomass.

In this study, removal of lead (II) and cadmium (II) ions from aqueous solutions by using blacktorn (Paliurus spina-christi MILL.) as a biomass was investigated. To clarify the biosorption process, the biomass was characterized by FT-IR (Fourier Transform Infrared Spectroscopy) spectra, SEM (Scanning Electron Microscope)images and EDX (Energy Dispersive X-ray ) analyses. The effect of parameters such as particle size, pH, biomass dosage, contact time and initial metal ion concentration on the biosorption yield was investigated. At the biosorption of both metals onto biomass, particle size of 150 µm and temperature of 40 oC were found to be the optimum values. Highest biosorption yield was obtained at pH 5.5 and at the the biomass dosage of 2 g/L at Pb (II) biosorption while the pH 5 and the 6 g/L were the optimum values at Cd (II) biosorption. Biosorption equilibrium was approached within 50 min. at Pb (II) but within 60 min. at Cd (II). Experimental data was applied to the Langmuir and Freundlich isotherm models to determine the best fitting model and the maximum biosorption capacity was found to be 231,7 mg/g and 36,84 mg/g for Pb (II) and Cd (II), respectively. Biosorption kinetic parameters were also studied and for both of the metals pseudo-second-order kinetic model was determined as applicable. As a result it was decided that blacktorn (Paliurus spina-christi MILL.) could be used as an effective biomass at the biosorption of Pb(II) and Cd(II).