Chemoselective catalytic oxidation of glycerol with air on platinum metals

Garcia, Régis; Бессон, М.; Gallezot, P.

doi:10.1016/0926-860x(95)00048-8

Cited by 323 publications

(293 citation statements)

References 27 publications

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“…35,34 This finding contrasts with earlier studies, which erroneously compared similar loading Pt and Pd catalysts possessing different dispersions, and hence unfairly concluded that palladium was far 50 superior to platinum. 45,46 Comparison with Pd/silica analogues 35,34 reveals significantly higher levels of C=C hydrogenation over platinum, consistent with the latter's performance in liquid phase alkene hydrogenation. 47 Styrene formation during cinnamyl alcohol 10 selox over Pd/silicas is indicative of the presence of palladium metal, 35 and by analogy, may reflect in-situ reduction of surface PtO2 under our reaction conditions.…”

Section: Cinnamyl Alcohol Selective Oxidationmentioning

confidence: 59%

Tunable Pt nanocatalysts for the aerobic selox of cinnamyl alcohol

et al. 2013

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The selective aerobic oxidation of cinnamyl alcohol over Pt nanoparticles has been tuning via the use of 5 mesoporous silica supports to control their dispersion and oxidation state. High area two-dimensional SBA-15, and three-dimensional, interconnected KIT-6 silica significantly enhance Pt dispersion, and thus surface PtO 2 concentration, over that achievable via commercial low surface area silica. Selective oxidation activity scales with Pt dispersion in the order KIT-6 ≥ SBA-15 > SiO 2 , evidencing surface PtO 2 as the active site for cinnamyl alcohol selox to cinnamaldehyde. Kinetic mapping has quantified key 10 reaction pathways, and the importance of high O 2 partial pressures for cinnamaldehyde production.

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Section: Cinnamyl Alcohol Selective Oxidationmentioning

confidence: 59%

Tunable Pt nanocatalysts for the aerobic selox of cinnamyl alcohol

et al. 2013

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“…Doping of noble metal catalysts with oxygen donors such as Ce [122] or Bi [132] was also found very effective in promoting their oxidation power. The donor atoms preferentially crystallise in the vicinity of the noble metal particles creating a high number of contact points that ensure both an excellent oxygen transfer and protection of the noble metal surface against over-oxidation [122].…”

Section: Preparation and Characterisationmentioning

confidence: 99%

Carbon materials and catalytic wet air oxidation of organic pollutants in wastewater

et al. 2005

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“…19 Metal-supported catalysts are usually employed in the glycerol oxidation, producing many compounds, such as glyceric, mesoxalic and hydropyruvic acid. 20,21 Dehydration of glycerol is known to occur under acid-catalyzed conditions, following two pathways: dehydration of the primary hydroxy group affords hydroxy-acetone or acetol as the main product, whereas dehydration of the secondary hydroxy group produces 3-hydroxypropanal, which can be subsequently dehydrated to acrolein (Scheme 2), an important chemical used in the industrial production of acrylic acid and amino-acids such as methionine. The economic importance of glycerol dehydration to acrolein was recently addressed in a short review, 22 which also discussed the use of different catalytic systems.…”

Section: Introductionmentioning

confidence: 99%

Oxidative dehydration of glycerol to acrylic acid over vanadium-impregnated zeolite beta

Pestana¹,

Guerra²,

Ferreira³

et al. 2013

J. Braz. Chem. Soc.

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A desidratação oxidativa do glicerol a ácido acrílico foi estudada com o uso de zeólita Beta impregnada com vanádio. Os catalisadores foram preparados por impregnação úmida do metavanadato de amônio sobre a zeólita Beta na forma amoniacal, seguida de calcinação em ar a 823 K. A impregnação reduziu a área superficial específica, mas não afetou significativamente a acidez (Brønsted e Lewis) da zeólita. A avaliação dos catalisadores foi realizada num reator de leito fixo usando ar como gás de arraste e injetando o glicerol por meio de uma bomba seringa. Acroleína foi o principal produto formado, tendo também sido observados acetaldeído e hidróxi-acetona (acetol). O ácido acrílico foi formado em aproximadamente 25% de seletividade a 548 K sobre as zeólitas impregnadas. O resultado pode ser explicado por análises de XPS (espectroscopia fotoeletrônica de raios X), que mostraram uma boa dispersão de vanádio nos poros da zeólita.The oxidative dehydration of glycerol to acrylic acid was studied over vanadium-impregnated zeolite Beta. Catalysts were prepared by wet impregnation of ammonium metavanadate over ammonium-exchanged zeolite Beta, followed by air calcination at 823 K. Impregnation reduced the specific surface area, but did not significantly affected the acidity (Brønsted and Lewis) of the zeolites. The catalytic evaluation was carried out in a fixed bed flow reactor using air as the carrier and injecting glycerol by means of a syringe pump. Acrolein was the main product, with acetaldehyde and hydroxy-acetone (acetol) being also formed. Acrylic acid was formed with approximately 25% selectivity at 548 K over the impregnated zeolites. The result can be explained by XPS (X-ray photoelectron spectroscopy) measurements, which indicated a good dispersion of the vanadium inside the pores.Keywords: glycerol, acrylic acid, zeolite, dehydration, oxidation IntroductionGlycerol is usually found in combination with fatty acids of natural occurrence forming the triglycerides. Today, the major source of glycerol is the transesterification of oils and fats to produce biodiesel. 1 In this reaction, a molecule of triglyceride reacts with three molecules of methanol, under base catalysis conditions, to afford three molecules of fatty acid methyl esters (the biodiesel) and a molecule of glycerol (Scheme 1). In recent years, the growing concern about global warming has motivated the use of biofuels. Biodiesel, together with bioethanol, is one of the most important biofuels used nowadays.For each 90 m 3 of biodiesel produced by transesterification, about 10 m 3 of glycerol are obtained. The worldwide glycerol production will reached 2 approximately 1.2 million tons in 2012 and most of this production will come from the biodiesel industry. In Brazil, for instance, there is a mandatory blend of 5% of biodiesel in the petrodiesel, which represents an annual glycerol production of approximately 300,000 tons. The traditional markets for glycerol are cosmetics, soaps, pharmaceuticals and personal care products. However, with the increasing ...

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Chemoselective catalytic oxidation of glycerol with air on platinum metals

Cited by 323 publications

References 27 publications

Tunable Pt nanocatalysts for the aerobic selox of cinnamyl alcohol

Tunable Pt nanocatalysts for the aerobic selox of cinnamyl alcohol

Carbon materials and catalytic wet air oxidation of organic pollutants in wastewater

Oxidative dehydration of glycerol to acrylic acid over vanadium-impregnated zeolite beta

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