Toluene, as a strong carcinogen, is widely found in the newly renovated rooms, shopping malls, and workshops. Photocatalytic oxidation has great superiority and application prospects for the degradation of toluene. However, low photocatalytic efficiency under visible-light irradiation arising from easy agglomeration of the solid catalysts hinders their photodegradation of toluene gas. In this work, heterostructured TiO 2 /WO 3 photocatalysts were fabricated via an electrospinning technology combining the hydrothermal treatment. The special microstructure and composition allowed the photogenerated electrons quickly transfer from the TiO 2 nanofibers to the WO 3 nanorods, and thus effectively reduced the recombination of photogenerated electrons and holes. Coupling TiO 2 with the narrow band-gap WO 3 broadened the spectral response range of TiO 2 . The heterostructured TiO 2 /WO 3 photocatalysts exhibited a remarkably higher degradation rate of toluene gas than that of the bare TiO 2 nanofibers under visible-light irradiation. The photocatalysts were deposited onto the inner walls of the photoreactor and some nylon meshes. The meshes were also placed in the photoreactor in a direction perpendicular to the air flow. The meshes increased the contact between photocatalysts in solid phase and toluene in gas phase, and about 85.3% of the toluene had been degraded in the experimental conditions.

ABSTRACT3-(N,N-dimethyldodecylammonium) propanesulfonic acid hydrogen sulfate [HSO 4 ]), a Brønsted acidic-surfactant-combined ionic liquid, was successfully prepared from cheap materials and applied to catalyze the esterification synthesis of ethyl oleate using oleic acid and ethanol as precursors. The produced condition of oleic acid ethyl ester was optimized including the amount of catalyst, reaction time, molar ratio and content of water. Under optimal condition (ethanol to oleic acid molar ratio, 3:1; amount of the catalyst, 5 wt% (based on the mass of oleic acid); reaction time, 3 h; reaction temperature, 78°C; and content of water, 0.4 wt%), the conversion of oleic acid was over 97%. Due to the reverse micelles formed by [HSO 4 ], the microreactor not only promoted the esterification toward the desired side of the ester, but also avoided the hydrolysis of ester. Moreover, the [SB3-12][HSO 4 ] could be reused by a simple decantation separating process and noticeable loss of catalytic activity was not observed even after being recycled for five cycles. The green system offers several advantages, such as excellent yield, efficient catalytic activity, free-solvent and simple operational procedure. ARTICLE HISTORY

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The densities and viscosities of binary mixtures of 1-ethyl-3-methylimidazolium heptachlorodialuminate and tetrachloroaluminate ionic liquids with different molar compositions were measured by high-precision vibrating tube densimeter and automated microviscometer from 293.15 to 353.15 K. On this basis, the excess molar volumes and excess viscosities of binary mixtures were also calculated for the first time. All the experimental data were well fitted by the empirical equations. According to the results of computational calculations, enhanced molecular symmetry and molar concentration of heptachlorodialuminate anion usually lead to higher density. The hydrogen bonding among ions is confirmed as one of the most important structural parameters in determining the viscosity of ionic liquids. It shows that Lewis acidic 1-ethyl-3-methylimidazolium chloroaluminate can be treated as the classic binary mixtures of heptachlorodialuminate and tetrachloroaluminate ionic liquids. Looser packing and/or weaker interionic interaction probably occurs after the formation of binary mixtures. The results and conclusions of this work will help to promote future research and application of chloroaluminate ionic liquids.