Epoxidation of propylene with H2 and O2 in the explosive regime in a packed-bed catalytic membrane reactor

Oyama, S. Ted; Zhang, Xiaoming; Lu, Jiqing; Gu, Yu; Fujitani, Tadahiro

doi:10.1016/j.jcat.2008.04.023

Cited by 252 publications

(123 citation statements)

References 17 publications

Supporting

Mentioning

114

Contrasting

Unclassified

Order By: Relevance

“…Mass and heat transfer limitation calculations for the five catalysts investigated in the present work are shown in the supplementary information in Tables S1, S2, and S3 and indicate negligible mass and heat transfer limitations. This is in agreement with previous results reported for nanostructured heterogeneous catalytic systems, where mass and heat transfer limitations were found negligible [38][39][40][41][42]. of Pt nanoparticles with some agglomeration due to the low BET surface area (a s ) of the perovskites.…”

Section: Catalytic Activitysupporting

confidence: 93%

Promotion of Pt Nanoparticles by Lattice Oxygen in SmFeO3 Perovskite Group for Carbon Monoxide and Ethylene Oxidation

et al. 2015

View full text Add to dashboard Cite

The novel Sm 1-x Ce x FeO 3-d (x = 0, 0.01, 0.05) (SCF) perovskites with and without 1 wt% of Pt nanoparticles (NPs) were investigated for carbon monoxide and ethylene oxidation in the temperature range of 25-350°C. All perovskites were predominantly ionic conductors, with ionic conductivities two orders of magnitude higher than the electronic contribution. Furthermore, the cerium doping increases the ionic conductivity of these materials at high temperatures. The bare SCF perovskites possessed catalytic activity for both reactions; however the Pt-supported catalysts had 50-100°C lower light-off temperatures than the corresponding perovskites. More significantly, the enhancement in the catalytic activity of the Pt/SCF family with respect to other Pt-supported catalysts was shown by the lower activation energies, which were 25.7 kJ/mol over Pt/Sm 0.95 Ce 0.05 FeO 3-d and 18.3 kJ/mol over Pt/Sm 0.99 Ce 0.01 FeO 3-d for CO and ethylene oxidation, respectively. The corresponding activation energies for Pt NPs supported on conventional cAl 2 O 3 were 57.1 and 32 kJ/mol, and on ionically conductive yttria-stabilized zirconia (YSZ) were 35.8 and 22 kJ/mol for CO and C 2 H 4 oxidation, respectively. The increased activity was attributed to the high ionic conductivity (O 2-) of the perovskite supports at 100-400°C that facilitates the spontaneous backspillover of O 2-promoters from the lattice to the gas-exposed Pt nanoparticle surface. The promoters alter the adsorption strength of reactants similar to the electrochemical promotion mechanism observed under polarization.

show abstract

Section: Catalytic Activitysupporting

confidence: 93%

Promotion of Pt Nanoparticles by Lattice Oxygen in SmFeO3 Perovskite Group for Carbon Monoxide and Ethylene Oxidation

et al. 2015

View full text Add to dashboard Cite

show abstract

“…Subsequent work indicated that materials containing Ti, for example TiO 2 (anatase) [46][47][48][49][50][51][52], mesoporous titanosilicates (Ti-SiO 2 ) [53][54][55][56][57][58][59][60][61][62][63][64][65][66][67], and microporous titanosilicalites (TS-1, TS-2, and T-Beta) were indispensable as supports [68][69][70][71][72][73][74][75][76][77]. Propene epoxidation with O 2 and H 2 over Au catalysts can be evaluated by propene conversion, PO selectivity, and H 2 efficiency.…”

Section: Gold Catalystsmentioning

confidence: 99%

“…Because a mixture of O 2 and H 2 is used, the potential risk of explosion cannot be excluded. Recently, Oyama et al [72] found that membrane reactors could enable the use of high concentrations of O 2 and H 2 (40% each) that were well within the explosive range. Nijhuis et al [104] also found that propene epoxidation with O 2 and H 2 in the explosive range could proceed in a microreactor system.…”

Section: Perspectivesmentioning

confidence: 99%

Gas-phase propene epoxidation over coinage metal catalysts

2011

View full text Add to dashboard Cite

Propene oxide (PO) is a very important bulk chemical and is produced on a scale of about 7.5 million tons per year. In industry, PO is produced via multiple reaction steps in the liquid phase, using hazardous chlorine or costly organic hydroperoxides as oxidants. Accordingly, development of a simple and green process to produce PO has been desired. This paper presents an overview of one-step propene epoxidation in the gas phase over coinage metal catalysts with a mixture of O 2 and H 2 or with molecular O 2 alone as oxidant. Silver (Ag) and gold (Au) catalysts can catalyze propene epoxidation with a mixture of O 2 and H 2 , with high selectivity, whereas copper (Cu) catalysts cannot. In this reaction Au catalysts are much more active than Ag catalysts. All the coinage metals can catalyze propene epoxidation by molecular O 2 , but with selectivity usually below 60%. The valence states of Cu species and the sizes of Ag particles and Au particles are of crucial importance in PO synthesis.

show abstract

“…Phase Transfer Catalysis) [136]. Another approach is to use a membrane to continuously remove the product, or to control the contact between the different reactants [137][138][139][140]. More recently, membrane reactors have also been used as an in situ nano-filtration system for the retention of catalytic nano-particles [141,142].…”

Section: Engineering Principlesmentioning

confidence: 99%

Selective Oxidation Catalysis: Opportunities and Challenges

et al. 2009

View full text Add to dashboard Cite

This contribution discusses some aspects crucial for designing optimal and sustainable oxidation processes. The catalyst, although at the heart of the system, is only one decisive design parameter amongst many others. Indeed, an interdisciplinary approach is required to improve existing processes, but also to rationally and systematically access opportunities for oxidation research on renewable feedstock compounds.

show abstract

Epoxidation of propylene with H2 and O2 in the explosive regime in a packed-bed catalytic membrane reactor

Cited by 252 publications

References 17 publications

Promotion of Pt Nanoparticles by Lattice Oxygen in SmFeO3 Perovskite Group for Carbon Monoxide and Ethylene Oxidation

Promotion of Pt Nanoparticles by Lattice Oxygen in SmFeO3 Perovskite Group for Carbon Monoxide and Ethylene Oxidation

Gas-phase propene epoxidation over coinage metal catalysts

Selective Oxidation Catalysis: Opportunities and Challenges

Contact Info

Product

Resources

About