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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.

Petroleum hydrocarbons can have adverse impacts on the environment and human health especially when they exist in the form of emulsion and aqueous solution. Nonwovens prepared by melt-blown method are a potential candidate for the removal of petroleum hydrocarbons. In this study, the processing-structure-oil sorption relationships of the PP (polypropylene) melt-blown nonwovens were investigated. Besides, the kinetics and mechanism of toluene sorption in simulated fire-fighting wastewater on the optimized prepared PP melt-blown nonwovens were studied at the static and dynamic conditions. The results showed that the web structure can be effectively controlled by adjusting the hot air temperature, metering pump speed and distance of collector to die to obtain an average fiber diameter of 3.0-10.5 μm, surface area of 0.5-1.5 m/g and porosity of 71.0-99.0 %. The sorption capacity for pure BTX medium increased with the decreasing fiber diameter and increasing porosity. The pseudo-second-order kinetic model better fitted the experimental data to describe the sorption of emulsified and dissolved form of toluene at static and dynamic conditions. The toluene sorption can be a combination of adsorption and capillarity, the contribution of which was about 1:14. [ABSTRACT FROM AUTHOR]