Phase cooperation between tin and antimony oxides in selective oxidation of isobutene to methacrolein I. Mechanical mixtures of SnO2 and $alpha;-Sb2O4

Weng, Lt.; Spitaels, N.; Yasse, B.; Ladrière, Jean; Ruíz, Patricio; Delmon, Bernard

doi:10.1016/0021-9517(91)90152-t

Cited by 45 publications

(4 citation statements)

References 25 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Antimony is widely used as a key element in mixed oxide catalysts for selective oxidation of hydrocarbons, such as Fe−Sb−O, − Sn−Sb−O, − V−Sb−O, ,− Mo−Sb−O, − and Re−Sb−O. − Many studies on the mixed oxides except for Re−Sb−O have demonstrated that excess antimony at surfaces is a clue to high selectivity to partially oxidized products. Allen and Bowker investigated propene oxidation on FeSbO 4 catalysts and reported that the catalyst surfaces were covered by antimony rich thin layers under the selective oxidation conditions .…”

Section: Introductionmentioning

confidence: 99%

Reversible Structure Transformation of Antimony Oxides on SiO₂Relevant to Selective Catalytic Oxidation of Ethanol

2003

View full text Add to dashboard Cite

Sb/SiO2 catalysts were prepared by chemical vapor deposition of Sb(OEt)3 on a SiO2 surface followed by water vapor admission and calcination. The catalysts were characterized by X-ray diffraction, X-ray photoelectron spectra, and X-ray absorption fine structure and by catalytic performance for selective oxidation of ethanol. At low loadings (2−4 wt %) Sb(OEt)3 reacted with surface OH groups on the SiO2 surface to form surface-attached Sb(III) species. At high Sb loadings (>5 wt %), in addition to the attached Sb(III) species, crystalline Sb2O3 species were formed after exposure to water vapor. The amount of crystalline Sb2O3 species increased with Sb loading, and 30−50% of Sb species existed as crystalline Sb2O3 at 7−12 wt %. Most of the Sb(III) species remained trivalent after calcination. On the other hand, the crystalline Sb2O3 was oxidized to Sb(V) and spread on the SiO2 surface. The spread antimony oxide species were active for selective catalytic oxidation of ethanol through a redox mechanism. When the spread antimony oxide species were reduced with ethanol, they were reversibly transformed to crystalline Sb2O3 species. This paper shows a dynamic structure change that occurs under the ethanol selective oxidation reaction conditions.

show abstract

Section: Introductionmentioning

confidence: 99%

Reversible Structure Transformation of Antimony Oxides on SiO₂Relevant to Selective Catalytic Oxidation of Ethanol

2003

View full text Add to dashboard Cite

show abstract

“…This phenomenon is of particular importance for oxidation reactions and can be easily followed by measuring the electrical properties in operando conditions. SnO 2 is among the oxides frequently used as a gas sensors and as a component of oxidation catalysts [1][2][3][4][5][6]. However, its activity is limited by its regularly low surface area.…”

Section: Introductionmentioning

confidence: 99%

Electrical and catalytic properties of SnO2/TiO2 measured in operando conditions

Munteanu

Căldăraru

Brătan

et al. 2011

Reac Kinet Mech Cat

View full text Add to dashboard Cite

The electrical conductivity and the catalytic activity of SnO 2 loaded TiO 2 (anatase) particles were investigated in operando conditions. SnO 2 depositions over commercial TiO 2 samples (Sigma Aldrich and Rhone Poulenc) were obtained by the impregnation method. The samples were characterized by XRD, SEM/EDX and BET-N 2 adsorption techniques. The AC electrical conductivity of the samples were measured between 25 and 400°C under various atmospheres. The effect of the reactant mixture on the electrical conductivity and the catalytic performances of the samples were tested in propene oxidation. The results showed that the conductivity of SnO 2 /TiO 2 samples depends strongly on the surface area of TiO 2 support. The reducing effect of propene is more evident for higher surface area catalysts, these one showing also higher activity. On the other hand, the SnO 2 deposition results in an increase of catalytic performances.

show abstract

“…Methyl methacrylate (MMA) as a very important chemical feedstock is widely used in the field of optical elements, aviation units, optical fibers, optical mirrors, robots, and transistor fabrication. − Meanwhile, methylacrolein (MAL) is the key stock for synthesis of MMA through selective oxidation followed by esterification or direct oxidative esterification with methanol. − Until now, the approaches to MAL are mainly focused on selective oxidation of isobutene or isobutane − and sec -amine-catalyzed Mannich reactions between propanal and formaldehyde, − which are summarized in Scheme .…”

Section: Introductionmentioning

confidence: 99%

“…In addition, a new crystal phase of α-Bi 2 Mo 3 O 12 , which was the source of cooperation effects, would form when the reaction temperature exceeded 400 °C. Under the optimal condition, the conversion and selectivity could reach up to 90 and 87%. , Except for these published papers, a lot of international patents have been applied and granted in the research area of Mo–Bi catalysts, and the conversion and selectivity changes from 95.4 to 99.5% and 83.3 to 97.1%, respectively, at the temperatures of 300–365 °C. − Also, further experimental studies in combination with theoretical calculation revealed the cooperation interaction existing among the composite oxides, which significantly affects the conversion and selectivity, and the catalytic sites formed through an oxygen spillover. − In addition to Mo–Bi catalysts, other bicomponent oxides and noble metal-supported catalysts are reported. Liu synthesized a series of Re–Sb–O compounds, which were active for oxidation of isobutylene to MAL with 83% selectivity at 350–450 °C, but the conversion was only 15% .…”

Section: Introductionmentioning

confidence: 99%

Synergistic Effects between Acid and Base Sites and Kinetic for Synthesis of Methylacrolein on the Cs-P/γ-Al₂O₃ Catalyst

Wang

Cai

2020

Ind. Eng. Chem. Res.

View full text Add to dashboard Cite

Methylacrolein (MAL) is traditionally synthesized from propanal and formaldehyde via the Mannich reaction instead of the aldol reaction in homogeneous catalytic systems due to the undesired self-condensation of propanal. Herein, the direct synthesis of MAL from propanal and trioxane via the aldol reaction was realized on an acid−base bifunctional Cs-P/γ-Al 2 O 3 catalyst, which exhibited good catalytic stability and could be prepared in a large scale with 54.5% yield and 100% selectivity. The influence of P elements on the structure and acid− base properties of Cs-P/γ-Al 2 O 3 and even on the selectivity of MAL, compared with Cs/γ-Al 2 O 3 , was elucidated through FT-IR, XRD, XPS, and CO 2 -and NH 3 -TPD characterizations in combination with catalytic activity evaluation. The synergistic effects between acid and base sites on MAL production were unveiled where the decomposition of trioxane into a formaldehyde unit followed by condensation between the formaldehyde monomer and propanal proceeded on the acid and base sites. Kinetics studies revealed that the trioxane decomposition into formaldehyde was zero-order-dependent on trioxane concentration and the condensation step conformed to the Langmuir−Hinshelwood mechanism, with activation barriers of 72 ± 0.2 and 65 ± 0.5 kJ/mol, respectively.

show abstract

Phase cooperation between tin and antimony oxides in selective oxidation of isobutene to methacrolein I. Mechanical mixtures of SnO2 and $alpha;-Sb2O4

Cited by 45 publications

References 25 publications

Reversible Structure Transformation of Antimony Oxides on SiO₂Relevant to Selective Catalytic Oxidation of Ethanol

Reversible Structure Transformation of Antimony Oxides on SiO₂Relevant to Selective Catalytic Oxidation of Ethanol

Electrical and catalytic properties of SnO2/TiO2 measured in operando conditions

Synergistic Effects between Acid and Base Sites and Kinetic for Synthesis of Methylacrolein on the Cs-P/γ-Al₂O₃ Catalyst

Contact Info

Product

Resources

About

Phase cooperation between tin and antimony oxides in selective oxidation of isobutene to methacrolein I. Mechanical mixtures of SnO2 and $alpha;-Sb2O4

Cited by 45 publications

References 25 publications

Reversible Structure Transformation of Antimony Oxides on SiO2Relevant to Selective Catalytic Oxidation of Ethanol

Reversible Structure Transformation of Antimony Oxides on SiO2Relevant to Selective Catalytic Oxidation of Ethanol

Electrical and catalytic properties of SnO2/TiO2 measured in operando conditions

Synergistic Effects between Acid and Base Sites and Kinetic for Synthesis of Methylacrolein on the Cs-P/γ-Al2O3 Catalyst

Contact Info

Product

Resources

About

Reversible Structure Transformation of Antimony Oxides on SiO₂Relevant to Selective Catalytic Oxidation of Ethanol

Reversible Structure Transformation of Antimony Oxides on SiO₂Relevant to Selective Catalytic Oxidation of Ethanol

Synergistic Effects between Acid and Base Sites and Kinetic for Synthesis of Methylacrolein on the Cs-P/γ-Al₂O₃ Catalyst