Amine-functionalized Polyacrylonitrile Solid Phase Extraction Method for On-line Separation and Enrichment of Copper and Lead in Environmental Water

A new type of amine functionalized polymer adsorption material was synthesized by using polyacrylonitrile as the raw material and triethylenetetramine (TETA) as the modified group. The morphology and structure of polymer materials were characterized by scanning electron microscope (SEM) and Fourier transform infrared spectrometer (FT-IR) . A fast on-line analysis method integrating separation , enrichment and determination was established by combining with a home-made solid phase extraction column and inductively coupled plasma mass spectrometry technology. The effects of pH, flow rate, volume and coexisting interfering ions on the separation and preconcentration of copper and lead were investigated. Under the conditions of pH 7, flow rate of 5 mL/min and sample volume of 50 mL, the adsorption efficiency of the metal ions could reach 95% within 10 min, and the interfering ions in real environmental water could be ignored. The dynamic adsorption saturation capacities of copper and lead were 15. 1 and 22. 5 mg/g, respectively. At a flow rate of 1 mL/min, 1% HNO3 solution was adopted to quantitatively elute the trace elements, and high enrichment factors were obtained. The limits of detection (LODs) of the method for copper and lead were 1. 7 and 2. 5 mu g/L, respectively, and the relative standard deviation (RSD %) was less than 3. 5%. Finally, the environmental Certified Reference Material GSB07-3186-2014 (CRM) was selected to verify the feasibility and accuracy of the on-line method. The prepared amine functionalized polyacrylonitrile had many advantages such as low cost, environmental friendliness, high adsorption efficiency and reusability. The online integrated method had the merits of easy to operate, fast, stable, and was suitable for the analysis of trace copper and lead in real environmental water samples.