Molybdenum Dopped Copper Ferrites as Active Catalysts for Alcohols Oxidative Coupling

Abstract

Copper ferrites dopped with molybdenum were studied in an oxidative coupling reaction between methanol and ethanol in the gas phase. The catalysts have been characterized by X-ray diffraction, where the presence of ferrite, magnetite, and tenorite phases was observed; scanning electron microscopy; UV-Vis spectroscopy; and Fourier-transform infrared spectroscopy, which highlighted the presence of octahedral coordination of isolated molybdena species. The catalyst with the highest activity in this reaction and with the highest selectivity to hydroxyacetone is the one that presents Lewis sites with weak acidity. The methyl and ethyl acetate selectivities are directly proportional to the Cu/Fe ratio. It has been observed that the presence of reduced copper sites is responsible for the selectivity in esters, while the presence of reduced iron and molybdenum sites is responsible for the acetol production.

Oxidative coupling of bio-alcohols mixture over hierarchically porous perovskite catalysts for sustainable acrolein production

“… 9 Another report used molybdenum dopped copper ferrite for oxidative coupling of primary alcohols, demonstrate that the aldehyde formation by dehydrogenation or by oxidation needs the presence of moderately basic sites (M 2+ –O 2− ). 37 …”

“…primary alcohols, demonstrate that the aldehyde formation by dehydrogenation or by oxidation needs the presence of moderately basic sites (M 2+ -O 2À ). 37 For selectivity, acidic sites exhibit a strong inuence on selectivity; the cross-selectivity seems to be controlled by acidity rather than basicity. On the other hand, using amphoteric catalysts as in our work, acrolein production is improved, and carbon oxides production is reduced, consequently allowing the catalyst to work at higher temperatures.…”

Magnetic Properties of Manganese-Zinc Soft Ferrite Ceramic for High Frequency Applications

“…EDS, XPS, SEM, and XRD data are presented, corroborated, and discussed with respect to the final usable composition of the material. Several similar structures and compositions are also presented and discussed elsewhere [16,17,18,19,20].…”

Microstructure and Magnetic properties of ferrite nanoparticles synthesized by Co-precipitation method

“…3, in which observe four characterizing peak between 400-4000 cm -1 . There are two most intense peaks observed in spectra such as 471cm -1 and 550cm -1 , which are corresponding to the tetrahedral and octahedral vibrational modes [38,39] respectively. Non magnetic metal like molybdenum (Mo) incorporated spinel ferrite; it shifts bands to the higher wave number.…”

“…Hence peaks amplitude/intensity decreases for the lattice parameters modi cations or crystal defects. The characteristic molybdenum (O-Mo-O) bands appear in the range 984 cm -1 [38,53,54]. The shift in the bands positions can attribute to the reduction in lattice parameters for Mo doping [39].…”