HKUST-1 was impregnated effectively on millimeter-sized mesoporous γ-Al 2 O 3 beads under hydrothermal conditions, resulting in formation of a composite material HKUST-1@γ-Al 2 O 3 that features high specific surface area, remarkable enhanced mechanical strength, chemical and thermal stability, and low cost. The composite material exhibited excellent performance with the adsorptive desulfurization capacity of 59.7 mg S/g MOF (versus 49.1 mg S/g MOF for bare HKUST-1) for a model oil composed of dibenzothiophene (with the initial S-content being 1000 ppmw S ) and n-octane. Experimental results also revealed that HKUST-1@γ-Al 2 O 3 could reduce 35 ppmw S sulfur content of the model oil lower than 9.6 ppmw S at a ratio of HKUST-1@γ-Al 2 O 3 to oil over 30 wt %, indicating effectiveness for deep adsorptive desulfurization. The Gibbs free energy for DBT adsorption by HKUST-1@γ-Al 2 O 3 was found smaller than that by HKUST-1 due to efficient utilization of active centers, shorter diffusion channels and larger specific surface area of nanosized HKUST-1 particles formed under confined environment of γ-Al 2 O 3 channels/pores. Remarkably, the used HKUST-1@γ-Al 2 O 3 beads can easily be regenerated by acetone washing and the adsorptive desulfurization capacity just slightly decreased after experiencing five recycles. The results indicate that the as-synthesized HKUST-1@γ-Al 2 O 3 beads have great potential as an adsorbent for adsorptive desulfurization in practical applications.

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The photocatalytic potential of a derivative family of the Keplerate type nano-porous Mo-O based polyoxometalates with general formula [Mo 72 VI Mo 60 V O 372 (L) 30 (H 2 O) 72 ] nÀ (L ¼ CH 3 COO À , SO 4 2À ) (denoted Mo 132 ) has been evaluated by a prototype photocatalytic decoloration reaction of aqueous rhodamine B. The Mo 132 anions are found to be photocatalytically active centers, however they are unstable and subjected to decomposition in the solution form. The introduction of organic counter cations such as tetrabutylammonium (n-Bu 4 N + ) and dioctadecyldimethylammonium (DODA + ) can endow significant stability to the giant anions during the catalytic process. TOC changes and GC/MS measurements were done to identify the degradation products. Among the derivatives, compound 2composed of n-Bu 4 N + and Mo 132 (L ¼ CH 3 COO À ) has been found to be the most active one towards the photocatalytic decoloration of RhB solution. The analytical mechanism indicates that both OH radicals and 1 O 2 participate in the photo degradation process.

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