Natural Analcime Zeolite Modified with Neothorin for Preconcentration and Determination of Trace Amounts of Lead by Flame Atomic Absorption Spectrometry

An analytical method using natural Analcime Zeolite modified with Neothorin for preconcentration of lead, in a column system, and their sequential determination by flame atomic absorption spectrometry (FAAS), was developed. In this work, lead was adsorbed onto natural Analcime Zeolite modified with Neothorin and then was recovered by 5.0 mL of 2 M nitric acid. Solution of lead passed through a glass column packed with 100mg of the sorbent material, at pH 5.0, and lead eluted with 2 M HNO3 at a flow rate of 2.0 mL min-1. A 4.11ppb detection limit for the preconcentration of aqueous solution of lead was obtained. The relative standard deviation (RSD) for eight replicate determination at the 5μg mL-1 lead level was 4.8%.The calibration graph using the preconcentration system was linear from 0.1 to30 μg mL-1 in final solution with a correlation coefficient of 0.9994.This method was successfully applied for determination of lead in various samples.

Keywords:

Lead determination , Preconcentration , Modified silica gel , Atomic absorption spectrometry