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Ordered mesoporous sulfonic acid functionalized ZrO2/organosilica catalysts (SO42−/ZrO2‐PMO‐SO3H) bearing tunable Brønsted, and Lewis acid site distributions were prepared by a P123‐directed sol‐gel co‐condensation route followed by ClSO3H functionalization. As‐prepared catalysts were applied in the conversion of glucose to ethyl levulinate in ethanol medium. The SO42−/ZrO2‐PMO‐SO3H‐catalyzed target reaction followed a glucose‐ethyl glucoside‐ethyl fructoside‐5‐ethoxymethylfurfural‐ethyl levulinate pathway dominated by the synergistic effect of the super strong Brønsted acidity, and moderate Lewis acidity of the catalysts. Additionally, by combining the advantages of the considerably high Brønsted (696 μeq g−1), Lewis acid site density (703 μeq g−1), optimal Brønsted/Lewis molar ratio (0.99), and excellent porosity properties, the SO42−/ZrO2‐PMO‐SO3H1.0 obtained at an initial Si/Zr molar ratio of 1.0 exhibited the highest ethyl levulinate yield (42.3 %) among the various tested catalysts. Moreover, the SO42−/ZrO2‐PMO‐SO3H can be reused three times without obvious changes in activity, morphology, and chemical structure. Super sweet for the super strong: SO42−/ZrO2‐PMO‐SO3H catalysts with super strong Brønsted acidity, and moderate Lewis acidity exhibit high yield of ethyl levulinate from glucose conversion. [ABSTRACT FROM AUTHOR]

Abstract: New and efficient heterogeneous photocatalytic materials, H3PW12O40/TiO2 and H6P2W18O62/TiO2, with anatase crystalline phase, dual-pore structures (micro- and meso-porosity), and nanometer sizes (average particle size of 6nm) were prepared by combination of the methods of sol–gel and hydrothermal treatment at a lower temperature (200°C, 2°C/min). Compositions, structures, physicochemical properties, and surface morphology of the composites were characterized by inductively coupled plasma atomic emission spectrum (ICP-AES), X-ray diffraction (XRD) patterns, UV diffuse reflectance spectroscopy (UV/DRS), 31P magic-angle spinning (MAS) NMR, Raman scattering spectra, nitrogen adsorption/desorption determination, and transmission electron microscopy (TEM), respectively. It indicated that the primary Keggin or Dawson structure remained intact after immobilization of the unit into TiO2 network, and hydrogen bonding and chemical interactions between the unit and the anatase network existed in the composites. Both of the composites exhibited visible-light photocatalytic activity to degradation of an aqueous organophosphorus pesticide, parathion-methyl, and the deactivation of the catalysts was hardly observed after five times catalytic cycling. [Copyright &y& Elsevier]

Given that industry is the major source of carbon emissions, clarifying the carbon transfer regularity triggered by industry production linkage is of great importance in realizing the synergistic development of industry to reduce pollution and carbon emissions. Based on the perspective of responsibility allocation, the study accounted for the industry carbon emissions and constructed a carbon transfer weighted directed network model and applied the social network analysis method to explore the structure of the industry carbon transfer network and its evolution characteristics from 2005 to 2020. The results showed that： ① The overall carbon emissions of industries from 2005 to 2020 presented a rapid growth trend and large differences occurred in emissions between industries. ② The scale of the carbon transfer network was expanding rapidly and the characteristics of the small-world network were significant. ③ The community structure of the carbon transfer network was obvious, including four optimal associations： high carbon emission, carbon transmission, carbon endogenous, and high spillover. ④ The construction industry and the metal smelting and rolling processing industry were the core of the carbon transfer network structure, with strong network control. In view of the above characteristics, we proposed countermeasures and suggestions in terms of implementing the allocation of carbon emission reduction responsibilities and differentiated emission reduction measures for associations as well as focusing on the management of core nodes of the network, with the intent of providing cross-sectoral synergistic emission reduction ideas for the development of sustainable low-carbon transformation in China's industry sector.

Morphology evolution of sulfonic acid functionalized organosilica nanohybrids (Si(Et)Si-Pr/ArSO3 H) with a 1D tubular structure (inner diameter of ca. 5 nm), a 2D hexagonal mesostructure (pore diameter of ca. 5 nm), and a 3D hollow spherical structure (shell thickness of 2-3 nm and inner diameter of ca. 15 nm) was successfully realized through P123-templated sol-gel cocondensation strategies and fine-tuning of the acidity followed by aging or a hydrothermal treatment. The Si(Et)Si-Pr/ArSO3 H nanohybrids were applied in synthesis of alkyl levulinates from the esterification of levulinic acid and ethanolysis of furfural alcohol. Hollow spherical Si(Et)Si-Pr/ArSO3 H and hexagonal mesoporous analogues exhibited the highest and lowest catalytic activity, respectively, among three types of nanohybrids; additionally, the activity was influenced by the -SO3 H loading. The activity differences are explained in terms of different Brønsted acid and textural properties, reactant/product diffusion, and mass transfer rate, as well as accessibility of -SO3 H sites to the reactant molecules. The reusability of the nanohybrids was also evaluated., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)