RESUMO
The preparation, characterization, and uranium (VI) adsorption properties of tri-amidoxime modified marine fungus material (ZZF51-GPTS-EDA-AM/ZGEA) were investigated in this study. ZGEA was synthesized by four steps of condensation, nucleophilic substitution, electrophilic addition, and nitrile amidoxime and characterized by a series of methods containing FT-IR, TGA, SEM, and BET. Contrasted with uranium (VI) adsorption capacity of original fungus mycelium (15.46 mg g-1) that of the functional material (584.60 mg g-1) was great under the optimal factors such as uranium (VI) ion concentration 40 mg L-1, solid-liquid ratio 50 mg L-1, pH of solution 5.5, and reaction time 120 min. The above data were obtained by the orthogonal method. The cyclic tests showed that ZGEA had good regeneration performance, and it could be recycled at least five adsorption-desorption processes. The thermodynamic experimental adsorption result fitted Langmuir and Freundlich models, which explored monolayer and double layers of uranium (VI) adsorption mechanism, and the kinetic adsorption results were in better consistent with the pseudo-second-order and pseudo-first-order dynamic models (R2 > 0.999).
Assuntos
Urânio/análise , Adsorção , Fungos , Concentração de Íons de Hidrogênio , Cinética , Oximas , Espectroscopia de Infravermelho com Transformada de Fourier , TermodinâmicaRESUMO
In this study, a new type of drug delivery carrier, the hollow magnetic silybin molecularly imprinted polymer (HMMIP) with a unique core-shell structure where the hollow magnetic core Fe3O4 was wrapped by mesoporous silica and imprinted layer, was prepared from methacrylic acid (MAA, functional monomer), ethylene glycol dimethacrylate (EGDMA, cross-linker), and silybin (a drug template) by reverse atom radical transfer polymerization method (RATRP), and characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray diffractometer (XRD), vibrating sample magnetometer (VSM), thermo-gravimetric analysis (TGA), transmission electron microscopy (TEM), and Brunauer-Emmett-Teller analysis (BET). Its adsorption performance was evaluated by the isotherm/kinetic models and the selectivity for silybin with 15.40â¯mgâ¯g-1 of adsorption capacity and 2.13 of selectivity factor α, respectively. The drug release experiment showed the prepared polymer had the properties of silybin sustained release agent, because it could last to release silybin for 36â¯h in the medium of pH 2.0 at physiological temperature. In addition, the resuability experiment indicated the imprinted material had the good stability and reproducibility. So HMMIP should be of the potential value applied in drug delivery in the future.