Synthesis of poly(N-aminoethyl)acrylamide chelating fiber and properties of concentration and separation of noble metal ions from samples

摘要

A new kind of poly(N-aminoethyl)acrylamide chelating fiber was synthesized from nitrilon (an acrylonitrile-based synthetic fiber) and used for the concentration and separation of traces of noble metal ions from solution. The results showed that 16-80ng ml~(-1) of Au(III), Pt(IV), Pd(IV), Ir(IV), Ru(III) and Rh(III) can be quantitatively concentrated by the fiber up to a flow rate of 20 ml min~(-1) at pH 3, and can be desorbed quantitatively with an eluting agent from the fiber column with recoveriesof 96-100%. For a fiber reused 10 times, the recoveries of these ions were still over 94%, and a 100-1000 times excess of Fe(III), Al(III), Ca(II), Mg(II), Ni(II), Co(II), Cu(II) and Zn(II) caused no interference in the determination of these ions by inductively-coupled plasma atomic emission spectrometry. The capacities of the fiber for the analytes were in the range 0.80-2.62 mol g~(-1). The relative standard deviation of the method was between 0.02% and 2.6%. Recoveries of a standard added to a realsample were 96.8-99.2%. The average error for the analysis by this method for a powder sample was < 3.5%. The IR spectra of the analyte-bearing fiber showed that these ions coordinated to nitrogen sites in the fiber.