In this study, the synergistic adsorption behavior of palladium [Pd(II)], molybdenum [Mo(VI)], and zirconium [Zr(IV)] in simulated high-level liquid waste was systematically investigated based on various factors, such as the contact time, concentration of nitric acid , adsorption amount, and temperature using a silica-based adsorbent impregnated with N,N′ -dimethyl- N,N′ -di-n-hexyl-thiodiglycolamide (Crea) and 2, 2′, 2′ -nitrilotris[ N,N -bis(2-ethylhexyl)acetamide] (TAMIA-EH). The adsorption rates of Pd(II), Mo(VI), and Zr(IV) in this synergistic adsorption system were high; thus, equilibrium states could be obtained in only 1 h with high uptake percentages of more than 90%. The adsorption abilities of Pd(II), Mo(VI), and Zr(IV) were only slightly affected by variation in the concentration of nitric acid in the range of 0.1–5 M and solution temperature in the range of 288–313 K. Selective stripping of the adsorbed Re(VII), Pd(II), Zr(IV), and Mo(VI) was successfully achieved under elution with 5 M HNO 3 , 0.2 M Tu (pH 1), 50 mM DTPA (pH 2), and 50 mM DTPA dissolved in 0.5 M Na 2 CO 3 (pH 11) solutions using the chromatography method. In addition, the adsorption performance in solid-state was studied using the particle-induced X-ray emission (PIXE) method; the obtained results were in good agreement with the results obtained via column separation.
Targeting CO 2 capture application, a new strategy for building multiple adsorption sites in metal-organic framework MIL-101(Cr) was constructed through the incorporation of diethylenetriamine-based ionic liquid (DETA-Ac) via a post-synthetic modification approach. The DETA-Ac, with multi-amine-tethered cation and acetate anion, could not only provide additional binding sites, but also enhance the affinity of framework surfaces toward CO 2 . Simultaneously, the high surface area and large cage size of MIL-101(Cr) ensured the better dispersion of IL, thus exposing more active sites for CO 2 adsorption. In addition, enough free space was still retained after functionalization, which facilitated CO 2 transport and allowed the Cr(III) sites deep within the pores to be accessed. The multiple adsorption sites originating from IL and MOF were found to synergistically affect the CO 2 capture performance of the composite. The adsorption capacity and selectivity of DETA-Ac@MIL-101(Cr) for CO 2 were significantly improved. The higher isosteric heats of adsorption (Q st ) evidenced the stronger interaction between the composite and CO 2 molecules. Moreover, a possible two-step mechanism was proposed to reveal the manner in which CO 2 bound to the IL-incorporated frameworks. Despite the relatively high initial Q st value, the DETA-Ac@MIL-101(Cr) could be easily regenerated with almost no drop in CO 2 uptake during six cycles.
危险品化学品经营许可证（带存储）