Selective Oxidation of Methanol to Dimethoxymethane over Mesoporous Al‐P‐V‐O Catalysts

Abstract

The synthesis and application of bifunctional mesoporous Al‐P‐V—O catalysts with both acidic and redox sites for selective oxidation of methanol to dimethoxymethane (DMM) is described. The catalysts were characterized by N2 adsorption/desorption, X‐ray diffraction, temperature‐programmed desorption, X‐ray photoelectron spectroscopy, and infrared spectroscopy. It is shown that porosity; redox property and surface acidity of the catalysts were greatly influenced by the Al/V/P ratio. The synergistic effect of phosphorus and vanadium was investigated. Al‐P‐V—O catalysts exhibited good catalytic activity because of the controlled reducibility and the acidic sites. © 2013 American Institute of Chemical Engineers AIChE J, 59: 2587–2593, 2013

Coupling reaction between methanol dehydrogenation and maleic anhydride hydrogenation over zeolite‐supported copper catalysts

“…The NH 3 desorption peaks for Cu/ZSM-5(260) and Cu/ZSM-5(360) catalysts shifted to high temperatures compared to those for Cu/ZSM-5(25) catalysts, meaning that the acidity of the acid site became stronger with increasing silica content. For the Cu/b (25) catalysts, three NH 3 desorption peaks were observed in their NH 3 -TPD profiles, showing that the Cu/b(25) catalysts had weak-, medium-, and strong-strength acid sites. The acidities of the Cu/zeolite catalysts were calculated according to the areas of their NH 3 desorption peaks.…”

“…Then, MF was formed by the reaction between formaldehyde and methanol . The formation of MF from formaldehyde was rapid, and the formation of formaldehyde was the rate‐controlling step, which appeared to be a plausible explanation for the absence of formaldehyde in the products . Besides, DME could be produced by the intermolecular dehydration of methanol over acid sites.…”

“…The released water could react with formaldehyde to produce formic acid, resulting in the formation of CO 2 via formic acid decomposition. Furthermore, the intermediate formaldehyde could be converted to other products, such as dimethoxymethane and polymer . The formation of CO was through MF decomposition .…”

“…[11,12] The formation of MF from formaldehyde was rapid, and the formation of formaldehyde was the rate-controlling step, which appeared to be a plausible explanation for the absence of formaldehyde in the products. [25] Besides, DME could be produced by the intermolecular dehydration of methanol over acid sites. The released water could react with formaldehyde to produce formic acid, resulting in the formation of CO 2 via formic acid decomposition.…”

Alternative Liquid Fuels from Renewable Resources

“…Several reports on vanadium‐based catalysts have been published and exemplarily, three examples will be considered in the following. A mesoporous bifunctional catalyst with the general composition Al‐P‐V‐O has been reported by Chen et al . It could be shown that there is a synergetic effect of phosphorous and vanadium, which has a significant influence on the redox and acid properties of the catalyst.…”