Cuban zeolite for lead sorption: application for water decontamination and metal quantification in water using nondestructive techniques

Abstract

In the present paper, a Cuban clinoptilolite-type zeolite was used as lead sorbent. The effect of chemical conditioning with 1 mol L−1 NaCl, NaOH and NH3 solutions at room temperature on the ion exchange capacity for lead uptake by clinoptilolite has been investigated. According to the batch experiments, NH3-treated clinoptilolite exhibited the highest sorption capacity. For this material, the effect that contact time, solid-to-liquid ratio and pH have on the removal of lead from aqueous solutions was comprehensively analyzed, and the most suitable values for these parameters were selected afterward. The pseudo-second-order kinetic model was appropriate for the description of the kinetic performance of the sorption. The Langmuir and Freundlich isotherm models were applied to describe sorption process, and the best fit was reached by using the Freundlich model. The nondestructive techniques, namely particle-induced X-ray emission and X-ray fluorescence, have successfully been evaluated for determining lead concentration in water by its concentration in zeolite. In addition, the more traditional flame atomic absorption spectrometry determination of lead in water was also improved.