Application of Some Natural Porous Raw Materials for Removal of Lead and Zinc from Aqueous Solutions

This chapter discusses the adsorption of lead and zinc ions onto a natural zeolite (clinoptilolite) and zeolite bearing tuff (stilbite) from aqueous solution, whereby the main parameters were the effects of initial pH of solution, mass of adsorbent, and initial metal concentration in solution. The physical and chemical properties of the natural materials used are characterized by X-ray diffraction, scanning electron microscopy, energy-dispersive spectroscopy, and AES–ICP. Determination of the maximum capacity of adsorbents for lead and zinc removal under the studied conditions is the main objective of the equilibrium studies. Experimental data are fitted to the Freundlich and Langmuir adsorption models. The adsorption of lead and zinc ions from diluted solution onto natural zeolite and zeolite bearing tuff occurs efficiently. Determination of the impact of the studied parameters on the efficiency of removal of lead and zinc ions from the solution showed that in the studied range, in the case of lead ions, there were not any significant changes found, but in the case of zinc ions, removal was most effective at lower concentration of zinc ions, higher mass of adsorbents, and higher pH value of the solution