Al−MCM-41 adsorbents with different SiO2/Al2O3 molar ratios (100, 50, and 30) were synthesized and used for desulfurization of a commercial diesel fuel (sulfur content = 1786 ppmw) at 373 K. The adsorbents were characterized by means of X-ray diffraction, N2 adsorption isotherm, Fourier transform infrared, and high-resolution transmission electron microscopy techniques. The adsorption capacity for sulfur-containing compounds was found to follow the order:  Al−MCM-41(50) > Al−MCM-41(30) > Al−MCM-41(100) (the number in parentheses is the SiO2/Al2O3 ratio hereafter). The efficiency of sulfur removal is 95% over Al−MCM-41(50) at the initial state and still above 75% after a cumulative effluent volume of 17 mL. The effect of the adsorption temperature on the adsorption capacity of Al−MCM-41(100) was investigated. The results indicate that high temperature is disadvantageous for desulfurization. After the regeneration of a spent Al−MCM-41(100) sample (calcined at 823 K for 6 h), there is good recovery of the adsorption capacity. In addition, with the presence of Cu+ ions in Al−MCM-41, there is enhancement in the adsorption capacity and sulfur removal efficiency at 373 K and the effect can be related to the formation of π complexation between sulfur-containing compounds and Cu+ ions.

A series of La 2 O 3 -V 2 O 5 /MCM-41 catalysts with high specific surface area were prepared by means of incipient wetness impregnation for the dehydrogenation of ethylbenzene to styrene using CO 2 as oxidant. At 600°C, the conversion of ethylbenzene and selectivity to styrene over 10La15V/MCM-41 after an on-stream time of 4 h was about 86.5 and 91.0%, respectively. The properties of the catalysts before and after the reaction were characterized using techniques such as X-ray diffraction, specific surface area, Fourier transform infrared spectroscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, temperature-programmed desorption, and oxidation. The high catalytic activity and stability of 10La15V/MCM-41 during dehydrogenation of ethylbenzene is attributed to an optimized La/V atomic ratio. The accumulation of amorphous carbon species on the external surface of La 2 O 3 -V 2 O 5 /MCM-41 is the cause for catalyst deactivation.

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