Preparation of ammonium phosphomolybdate polypropylene nonwovens adsorbent by radiation grafting method and its adsorption performance for Cs(I)

Glycidyl methacrylate (GMA) was grafted onto polypropylene (PP) nonwovens by electron-beam-induced pre-irradiation grafting, and ammonium phosphomolybdate (AMP) was physically loaded on the grafted polymer to prepare a composite material called PP-g-GMA@AMP. The loading rate of AMP was 5.72%, and the grafting rate of GMA was 32.41%. The maximum adsorption efficiency of Cs(I) by PP-g-GMA@AMP was 97.23% at pH=6. The adsorption kinetic behavior was in accordance with pseudo-second-order kinetic equation. The experimental results showed that the adsorption process using PP-g-GMA@AMP conforms to Langmuir adsorption model and the theoretical maximum adsorption capacity was 2.59 mg/g. PP-g-GMA@AMP showed good reusability and the adsorption capacity was reduced by only 9.91% after three repeated uses. PP-g-GMA@AMP showed excellent selective adsorption ability for Cs(I) in the presence of Na(I), Mg(II), and Ca(II). The distribution coefficient of Cs(I) on AMP was 120.45, while those of Na(I), Mg(II), and Ca(II) were 2.71, 1.23, and 1.84, respectively. According to the difference in partition coefficients, Cs(I) was separated from Na(I), Mg(II), and Ca(II) by dynamic column chromatography using a 0.5 mol/L NH4Cl eluent solution, and the Cs(I) effluent liquid was concentrated to one-fifth the volume of the injection solution.