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Fabio Rainone

Bio: Fabio Rainone is an academic researcher from École Polytechnique Fédérale de Lausanne. The author has contributed to research in topics: Partial oxidation & Catalysis. The author has an hindex of 9, co-authored 9 publications receiving 369 citations.

Papers
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Journal ArticleDOI
TL;DR: In this paper, surface vanadia species formed on vanadia/titania catalysts consisting of 0.2-2.6 monolayers of VOx have been characterized by FT-Raman spectroscopy under controlled atm., temp-programmed redn. in hydrogen (TPR), and soly. in dild.

103 citations

Journal ArticleDOI
19 Jul 2001-Langmuir
TL;DR: In this paper, the influence of potassium on the formation of surface vanadia species on V/Ti oxide catalysts contg. from 0.2 to 5 monolayers of vanadia (K/V at. surface ratio?1) has been investigated by temp. programmed redn.
Abstract: The influence of potassium on the formation of surface vanadia species on V/Ti oxide catalysts contg. from 0.2 to 5 monolayers of vanadia (K/V at. surface ratio ?1) has been investigated by temp. programmed redn. in hydrogen and by FT-Raman spectroscopy under dehydrated conditions. In the pure catalysts, monomeric and polymeric (metavanadate-like) species, qamorphousq and bulk cryst. V2O5 were detected depending on the surface vanadia loading. In the K-doped catalysts, vanadia species formed on the surface depend also on the K/V at. ratio. Even at small K/V ratios, K inhibits the formation of the polymeric species in favor of the qK-dopedq and/or qK-perturbedq monomeric species. These species possess lengthened V:O bonds with respect to the monomeric species in the undoped V/Ti oxides. At K/V = 1, the qK-dopedq monomeric species and qamorphousq KVO3 are mainly present on the surface. Redn. of vanadia forms in the K-doped catalysts takes place at higher temps. than in the catalysts where potassium was absent. The monomeric and polymeric species, which are the active sites in partial catalytic oxidn., have the lowest redn. temp. Vanadia species formed on the com. titania, contg. K, were also elucidated. The catalysts were characterized via XPS, high-resoln. transmission electron microscopy, and Brunauer-Emmett-Teller surface area measurements. [on SciFinder (R)]

58 citations

Journal ArticleDOI
TL;DR: In this article, a series of mesoporous ma-terials with pore dimensions greater than 20A have been synthesized using structure-directing templates and they have been found to be active for the vapourphase oxidation of toluene with molecular oxygen.
Abstract: Thesynthesesofthermallystablechromium-incorporatinghexagonalmesoporousaluminophosphateandcubicCr-MCM-48have been reported. Characterization of the catalysts was made using low angle XRD, N 2 adsorption, UV-VISDRS, thermalanalysis, ICP-AES and ESR. Mesoporous Cr-AlPO 4 and Cr-MCM-48 catalysts have been found to be active for the vapourphase oxidation of toluene with molecular oxygen. Mesoporous Cr-AlPO 4 is found to exhibit both acidic and redox propertiesand hence oxidation as well as dealkylation reactions are taking place in a concerted manner, whereas, the cubic silicateanalogue acts as a pure redox catalyst.© 2002 Elsevier Science B.V. All rights reserved. Keywords: Chromium; Aluminophosphates; Mesoporous materials; Partial oxidation 1. IntroductionAluminophosphate materials, recently developed ascrystalline microporous materials are of potential useincatalysis[1].Flanigenetal.[2]reportedtheincorpo-ration of various elements into the framework sites ofaluminophospahtes and the resulting systems are ac-tiveforvariouscatalytictransformations.However,thepore dimensions of these materials are not sufficient toaccommodate a broad spectrum of organic moleculesin their cavities. With the first discovery of M41S bythe Mobil researchers, a series of mesoporous ma-terials with pore dimensions greater than 20A havebeen synthesised using structure-directing templates

45 citations

Journal ArticleDOI
TL;DR: In this paper, the role of vanadia species (monomeric, polymeric, bulk) in catalytic toluene partial oxidation has been investigated using FT-Raman spectroscopy and TPR in H2.

39 citations

01 Jan 2003
TL;DR: In this article, pure and K-doped vanadia/titania catalysts were characterized by FT-Raman spectroscopy, TPR, TPD of pyridine and XPS.
Abstract: Pure and K-doped vanadia/titania catalysts have been studied by transient response method and in situ DRIFTS during toluene partial oxidn. They were characterized by FT-Raman spectroscopy, TPR, TPD of pyridine and XPS. In order to elucidate the role of different vanadia species for catalysis, the study was carried out in aerobic and anaerobic conditions. Monolayer species (monomeric and polymeric) are responsible for the catalytic activity and selectivity. Bulk V2O5 present in the catalysts with high concn. of vanadia supplies oxygen for the monolayer species easily reducible by toluene. This oxygen is necessary for the products formation and desorption in the absence of gaseous oxygen. Potassium at low concn. diminishes the total rate of toluene oxidn. and suppresses deactivation provided by cocking. This is due to transformation of the polymeric species to the not active K-doped monomeric ones. [on SciFinder (R)]

37 citations


Cited by
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Journal ArticleDOI
TL;DR: Theoretical work on catalyst precursors, resting states, and elementary steps, as well as model reactions complemented by spectroscopic studies provide detailed insight into the molecular mechanisms of oxidation catalyses and pave the way for preparative applications.
Abstract: Although catalytic reductions, cross-couplings, metathesis, and oxidation of CC double bonds are well established, the corresponding catalytic hydroxylations of CH bonds in alkanes, arenes, or benzylic (allylic) positions, particularly with O2, the cheapest, “greenest”, and most abundant oxidant, are severely lacking. Certainly, some promising examples in homogenous and heterogenous catalysis exist, as well as enzymes that can perform catalytic aerobic oxidations on various substrates, but these have never achieved an industrial-scale, owing to a low space-time-yield and poor stability. This review illustrates recent advances in aerobic oxidation catalysis by discussing selected examples, and aims to stimulate further exciting work in this area. Theoretical work on catalyst precursors, resting states, and elementary steps, as well as model reactions complemented by spectroscopic studies provide detailed insight into the molecular mechanisms of oxidation catalyses and pave the way for preparative applications. However, O2 also poses a safety hazard, especially when used for large scale reactions, therefore sophisticated methodologies have been developed to minimize these risks and to allow convenient transfer onto industrial scale.

225 citations

Journal ArticleDOI
TL;DR: Significant enhancement of the response and selectivity to o-xylene and toluene is attributed to the decrease in the hole concentration in NiO and the catalytic oxidation of methyl groups by Cr doping.
Abstract: Ultraselective and sensitive detection of xylene and toluene with minimum interferences of other indoor air pollutants such as benzene, ethanol, and formaldehyde is achieved using NiO hierarchical nanostructures doped with Cr. Pure and 1.15–2.56 at% Cr-doped NiO flower-like hierarchical nanostructures assembled from nanosheets are prepared by a simple solvothermal reaction and their gas sensing characteristics toward o-xylene and toluene gases are investigated. The 1.15 at% Cr-doped NiO hierarchical nanostructures show high responses to 5 ppm of o-xylene and toluene (ratio of resistance to gas and air = 11.61 and 7.81, respectively) and negligible cross-responses to 5 ppm of benzene, formaldehyde, ethanol, hydrogen, and carbon monoxide. However, pure NiO nanostructures show low responses to 5 ppm of o-xylene and toluene (ratio of resistance to gas and air = 2.01 and 1.14, respectively) and no selectivity toward any specific gas is observed. Significant enhancement of the response and selectivity to o-xylene and toluene is attributed to the decrease in the hole concentration in NiO and the catalytic oxidation of methyl groups by Cr doping.

221 citations

Journal ArticleDOI
TL;DR: New strategies of low-temperature synthesis from biomass may lead to the utilization of formic acid for the production of fuel additives, such as methanol; upgraded bio-oil; γ-valerolactone and its derivatives; and synthesis gas used for the Fischer-Tropsch synthesis of hydrocarbons.
Abstract: Formic acid is a widely used commodity chemical. It can be used as a safe, easily handled, and transported source of hydrogen or carbon monoxide for different reactions, including those producing fuels. The review includes historical aspects of formic acid production. It briefly analyzes production based on traditional sources, such as carbon monoxide, methanol, and methane. However, the main emphasis is on the sustainable production of formic acid from biomass and biomass-derived products through hydrolysis and oxidation processes. New strategies of low-temperature synthesis from biomass may lead to the utilization of formic acid for the production of fuel additives, such as methanol; upgraded bio-oil; γ-valerolactone and its derivatives; and synthesis gas used for the Fischer-Tropsch synthesis of hydrocarbons. Some technological aspects are also considered.

218 citations

Journal ArticleDOI
TL;DR: In this paper, the mechanism of toluene oxidation at room temperature over Mn/HZSM-5, Ag/HzSM-6, and Mn-Ag/HazSM-7 catalysts was investigated by in situ DRIFTS.

183 citations

Journal ArticleDOI
TL;DR: In this article, two major chemical processes, acidobasic and redox, track the adsorption mechanism on metal oxides and can be understood as acid-base processes.

143 citations