Adsorption Behavior of Lead(II) by Crosslinked Polyacrylonitrile and Its Application in Trace Analysis

A new method for the determination of Pb2+ in environmental water sample using crosslinked polyacrylonitrile as a solid-phase extractant and flame atomic absorption spectrometry(FAAS) as a sensitive detector has been developed.The adsorption of Pb2+ by crossslinked polyacrylonitrile and factors affecting the adsorption capacity were studied by AAS.The experimental results showed that at optimal adsorption conditions,e.g.,pH of adsorbate solution was 5.4,static adsorption time was 1.5 h and adsorption procedure was carried at room temperature,polyacrylonitrile as adsorbent has high adsorption capacity for Pb2+ which can reach 49.6 mg/g.Adsorption rate was 90% during the 1.5 h static adsorption time.Using 0.10 mol/L chloride acid as the desorption solvent to desorb the adsorbates,the enrichment factor and the recovery were 50 times and 97% respectively.Under enrichment factor of 50 times,the detection limits(3σ) was 5.3 μg/L and the relative standard deviation(RSD) was 2.1%.The established method was extended to the determination of environmental samples and the results were satisfactory(recovery was 92.9%～97.6%).These results indicate that the polymer has good regenerate capability.