Determination of Some Heavy Metals in Real Samples by FAAS after Preconcentration on 4-Nitro-2-(2-nitro-phenelazo)phenol Modified Activated Carbon

Abstract

A sensitive and simple method for determination of some heavy metals by flame atomic spectrometry after simultaneous preconcentration of trace heavy metals ions in some cereal and vegetable samples has been reported. The method is based on the adsorption of Cu 2+ , Fe 2+ , Zn 2+ and Pb 2+ on 4-nitro-2-(2-nitro-phenelazo)phenol (NNPP) loaded on activated carbon (AC). The adsorbed metals on activated carbon were eluted using 3 mL 4 mol L -1 nitric acid. The influences of the analytical parameters including pH, flow rate of sample and eluent, type and concentration of eluent, amount of adsorbent and sample volume were investigated. The recoveries of analytes were generally higher than 95%.