The One-Step Oxidation of Methanol to Dimethoxymethane over Nanostructure Vanadium-Based Catalysts

Abstract

The VO x -TiO 2 (VT-RC) and sulfated VO x -TiO 2 (VTS-RC) catalysts were prepared by rapid combustion method (RC) and evaluated by the one-step oxidation of methanol to dimethoxymethane (DMM). The results showed that the VT-RC and VTS-RC catalysts were consisted of nano-particles and exhibited pore structure. Compared with the coprecipitated VO x -TiO 2 (VT-CP) catalyst, the VT-RC catalyst showed more acidic sites and stronger reducibility. The addition of sulfate into VT catalyst further increased the number of acidic sites and had little effect on the reducibility. The catalytic test showed that the VT-RC catalyst exhibited high DMM selectivity (89.96% at 35% methanol conversion), which was further increased on VTS-RC catalyst (91.76% at 48% methanol conversion), and that was due to the larger number of acidic sites and stronger reducibility on these catalysts.

Effect of oxomolybdate species dispersion on direct methanol oxidation to dimethoxymethane over MoOx/TiO2 catalysts

“…Thus, a bifunctional catalyst is required, which must contain both acid and redox properties, in order to promote both the oxidation to FA and its subsequent condensation with methanol (Scheme ). Numerous research articles addressed the development of new catalysts for this reaction, whereby generally four types of catalysts were described based either on supported vanadium , ruthenium , rhenium or molybdenum . Regarding the fine‐tuning of the redox and the acid properties, several strategies can be employed.…”

Effects of reaction conditions on one‐step synthesis of methylal via methanol oxidation catalyzed by Mo:Fe(2)/ HZSM ‐5 catalyst

“…The increase in the reaction temperature is known to result in easier desorption of FA (chemisorbed on acidic sites). 39 The lowering of acidic strength additionally promoted FA desorption. The formic acid is further oxidized to form carbon dioxide and carbon monoxide.…”

Challenges and Opportunities in the Production of Oxymethylene Dimethylether

“…Both acids showed similar OME 1 selectivity of around 90 % and conversions between 41 % and 49 %. In another approach, V 2 O 5 /TiO 2 catalysts were modified with sulfur (VTiS), with rapid compression (RC) , , sol‐gel (SG) , , and mechanical grinding (MG) presenting the most efficient methodologies. More specifically, these catalysts afforded similar OME 1 selectivities; however, the conversion reached with these systems differed significantly ranging from 15 up to 49 %, respectively.…”

“…[43] The excellent oxidation properties of vanadium-based catalysts have to be combined with an acidic function, either by using an acidic support material or via the addition of acidic additives. [47,48], sol-gel (SG) [49,50], and mechanical grinding (MG) [49] presenting the most efficient methodologies. More specifically, these catalysts afforded similar OME 1 selectivities; however, the conversion reached with these systems differed significantly ranging from 15 up to 49 %, respectively.…”