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a b s t r a c tA bimetallic oxidation catalyst has been synthesized via wet impregnation of copper and iron over a mesoporous SBA-15 silica support. Physicochemical properties of the resulting material were characterized by XRD, N 2 physisorption, DRUVS, FTIR, Raman, SEM and HRTEM, revealing the structural integrity of the parent SBA-15, and presence of highly dispersed Cu and Fe species present as CuO and Fe 2 O 3 . The CuFe/SBA-15 bimetallic catalyst was subsequently utilized for the oxidative degradation of N,N-diethylp-phenyl diamine (DPD) employing a H 2 O 2 oxidant in aqueous solution.

Tungsten, in varying amounts, was incorporated into a SBA-16 structure via a one-pot direct synthesis method under an acidic medium using Pluronic F127 triblock co-polymer as a template and n-butanol as a co-surfactant. Tetraethyl orthosilicate (TEOS) and sodium tungstate were used as the Si and W sources, respectively. The resulting materials (denoted as W-SBA-16) are characterized for structural ordering, textural properties, and types of tungsten incorporation by techniques such as small-angle X-ray scattering (SAXS), X-ray diffraction (XRD), N2 sorption, high-resolution transmission electron microscopy (HR-TEM), diffuse-reflectance ultraviolet–visible light (DR-UV-vis) microscopy, temperature-programmed reduction in a hydrogen atmosphere (H2-TPR), and temperature-programmed desorption of ammonia (NH3-TPD). The surface area (823–354 m2/g) and pore volume (0.71–0.44 cm3/g) of the W-SBA-16 materials are found to decrease with an increase in tungsten loading (from 2.7 wt % to 30.4 wt % of the total sample). Isolated framework WO4 species and octahedrally coordinated polytungstate species are observed at all tungsten loadings, while bulk WO3 species are observed only at higher tungsten loadings. The W-SBA-16 materials display significant acidity that is tunable with tungsten loading, and they selectively catalyze the epoxidation of cyclohexene to cyclohexene oxide with H2O2 as an oxidant. The fact that bulk WO3 alone does not catalyze the reaction implies that the framework-incorporated W species and/or the polytungstate species are responsible for the observed catalysis. For this reaction, three-dimensional cubic mesostructured catalysts (W-SBA-16, W-KIT-6, and W-KIT-5) perform better than two-dimensional mesostructured (W-SBA-15) material. The problem of gradual tungsten leaching must be overcome for these catalysts to have practical utility.

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A family of copper oxide catalysts with loadings spanning 1 to 5 wt% were dispersed on a three dimensional, mesoporous TUD-1 silica through a hydrothermal, surfactant-free route employing tetraethylene glycol as a structure-directing agent. Their bulk and surface properties were characterized by N2 physisorption, XRD, DRUVS, EPR, TEM and Raman spectroscopy, confirming the expected mesoporous wormhole/foam support morphology and presence of well-dispersed CuO nanoparticles (~5-20 nm). The catalytic performance of Cu/TUD-1 was evaluated as heterogeneous Fenton-like catalysts for Bisphenol A (BPA) oxidative degradation in the presence of H2O2 as a function of [H2O2], and CuO loading. Up to 90.4 % of 100 ppm BPA removal was achieved over 2.5 wt% Cu/TUD-1 within 180 min, with negligible Cu leaching into the into the treated water.