Selectivity in Propene Dehydrogenation on Pt and Pt<sub>3</sub>Sn Surfaces from First Principles

Nykänen, L.; Honkala, Karoliina

doi:10.1021/cs400566y

Cited by 145 publications

(147 citation statements)

References 36 publications

(93 reference statements)

Supporting

Mentioning

142

Contrasting

Unclassified

Order By: Relevance

“…In the mean‐field approximation, the adsorbed species are distributed randomly over the surface and there is no interaction between the adsorbates. Hence, in the previous studies over transition‐metal catalysts, 68,69,74 the adsorbed propyl and H are thought of as widely separated species and H has no effect on the kinetics of the subsequent dehydrogenation reactions. However, as we know, the mean‐field approximation tends to be valid when the adsorbates repel one another and when the surface coverage is low.…”

Section: Resultsmentioning

confidence: 99%

Dual‐function catalysis in propane dehydrogenation over Pt₁–Ga₂O₃ catalyst: Insights from a microkinetic analysis

Chang

Wang

et al. 2020

AIChE Journal

View full text Add to dashboard Cite

The kinetics of propane dehydrogenation over single‐Pt‐atom‐doped Ga2O3 catalyst has been examined by combining density functional theory calculations and microkinetic analysis. The doping of Pt not only can improve the selectivity of the Ga2O3 catalyst by hindering the deep dehydrogenation reactions but also helps to achieve a long‐term stability by improving the resistance of Ga2O3 to hydrogen reduction. Microkinetic analysis indicates that upon Pt doping the turnover frequency for propane consumption is increased by a factor of 2.8 under typical operating conditions, as compared to the data on the pristine Ga2O3 surface. The calculated results suggest that the Pt1–Ga2O3 catalyst shows a bifunctional character in this reaction where the Pt–O site brings about dehydrogenation while the Ga–O site is active for desorbing H2, which provides a beautiful explanation for the previous experimental observation that even trace amounts of Pt can dramatically improve the catalytic performance of Ga2O3.

show abstract

Section: Resultsmentioning

confidence: 99%

Dual‐function catalysis in propane dehydrogenation over Pt₁–Ga₂O₃ catalyst: Insights from a microkinetic analysis

Chang

Wang

et al. 2020

AIChE Journal

View full text Add to dashboard Cite

show abstract

“…As a second reaction example, we will consider light alkane dehydrogenation, a reaction with ample industrial interest for which Pt is a major catalysts and which is operated a high temperature (360-600 °C). [63][64][65][66][67] The reaction produces light alkenes, that are very important intermediates for the production of bulk chemicals and polymers. The catalyst deactivates by coke formation and in many processes hydrogen is co-fed with the alkane in order to reduce the deactivation.…”

Section: Methane Activation On Pt 13 and Pt 13 H 26 Clustersmentioning

confidence: 99%

Metastable Structures in Cluster Catalysis from First-Principles: Structural Ensemble in Reaction Conditions and Metastability Triggered Reactivity

2018

View full text Add to dashboard Cite

Reactivity studies on catalytic transition metal clusters are usually performed on a single global minimum structure. With the example of a Pt cluster under a pressure of hydrogen, we show from first-principle calculations that low energy metastable structures of the cluster can play a major role for catalytic reactivity and that hence consideration of the global minimum structure alone can severely underestimate the activity. The catalyst is fluxional with an ensemble of metastable structures energetically accessible at reaction conditions. A modified genetic algorithm is proposed to comprehensively search for the low energy metastable ensemble (LEME) structures instead of merely the global minimum structure. In order to reduce the computational cost of density functional calculations, a high dimensional neural network potential is employed to accelerate the exploration. The presence and influence of LEME structures during catalysis is discussed by the example of H covered Pt clusters for two reactions of major importance: hydrogen evolution reaction and methane activation. The results demonstrate that although the number of accessible metastable structures is reduced under reaction condition for Pt clusters, these metastable structures can exhibit high activity and dominate the observed activity due to their unique electronic or structural properties. This underlines the necessity of thoroughly exploring the LEME structures in catalysis simulations. The approach enables one to systematically address the impact of isomers in catalysis studies, taking into account the high adsorbate coverage induced by reaction conditions.

show abstract

“…Hence, a periodic catalyst regeneration step is important in the above-mentioned industrial operations [19]. Many efforts have been made in improving the catalytic performance, including the addition of a second metal such as Sn, In, or Ga into Pt-based catalysts [20][21][22][23][24][25][26][27][28][29][30], or the modification of Cr-catalysts with alkali additives [31][32][33][34].…”

Section: Introductionmentioning

confidence: 99%

Catalytic propane dehydrogenation over In2O3–Ga2O3 mixed oxides

Tan

Gil

Subramanian

et al. 2015

Applied Catalysis A: General

View full text Add to dashboard Cite

A series of ternary mixed metal oxides containing Group III A elements (In, Ga, Al) is prepared by means of an alcoholic co‐precipitation method. Specifically, oxide catalysts with a molar composition of In/Ga/Al=5:15:80, 10:10:80, and 15:5:80 are reported. The chemical composition, redox properties, and catalyst structures are fully characterized, with the results suggesting that the indium, gallium, and aluminum moieties are well‐dispersed in the catalysts. The catalysts are evaluated for propane dehydrogenation (PDH) at 570 and 600 °C under 1 atm total pressure. The most effective catalyst with a composition of In/Ga/Al=5:15:80 provides 17 % conversion and approximately 86 % C3H6 selectivity with an initial activity of 4.6 mmol h−1 gcat−1 and 24.1 μmol h−1 m−2. The intrinsic activity on an active metal (i.e. indium and gallium) basis is approximately 3 times that of the In2O3–Ga2O3 family and approximately 3–9 times that of the In2O3–Al2O3 family. The catalyst deactivates with time on stream, and regeneration tests show that removal of surface coke and recovery of an In2O3 state helps to regain the initial activity, whereas reducing In2O3 domains into In0 does not allow for recovery of the performance. Raman analysis of the carbonaceous species deposited on the catalyst indicates catalysts with higher gallium content give more graphitic carbon, which correlates with higher C3H6 selectivity, whereas catalysts with more disordered coke are associated with lower selectivity. However, higher gallium content causes more coke formation, which leads to faster deactivation. This initial study of this family of mixed oxides suggests that an ideal In/Ga ratio may exist whereby catalyst properties may be optimized.

show abstract

Selectivity in Propene Dehydrogenation on Pt and Pt₃Sn Surfaces from First Principles

Cited by 145 publications

References 36 publications

Dual‐function catalysis in propane dehydrogenation over Pt₁–Ga₂O₃ catalyst: Insights from a microkinetic analysis

Dual‐function catalysis in propane dehydrogenation over Pt₁–Ga₂O₃ catalyst: Insights from a microkinetic analysis

Metastable Structures in Cluster Catalysis from First-Principles: Structural Ensemble in Reaction Conditions and Metastability Triggered Reactivity

Catalytic propane dehydrogenation over In2O3–Ga2O3 mixed oxides

Contact Info

Product

Resources

About

Selectivity in Propene Dehydrogenation on Pt and Pt3Sn Surfaces from First Principles

Cited by 145 publications

References 36 publications

Dual‐function catalysis in propane dehydrogenation over Pt1–Ga2O3 catalyst: Insights from a microkinetic analysis

Dual‐function catalysis in propane dehydrogenation over Pt1–Ga2O3 catalyst: Insights from a microkinetic analysis

Metastable Structures in Cluster Catalysis from First-Principles: Structural Ensemble in Reaction Conditions and Metastability Triggered Reactivity

Catalytic propane dehydrogenation over In2O3–Ga2O3 mixed oxides

Contact Info

Product

Resources

About

Selectivity in Propene Dehydrogenation on Pt and Pt₃Sn Surfaces from First Principles

Dual‐function catalysis in propane dehydrogenation over Pt₁–Ga₂O₃ catalyst: Insights from a microkinetic analysis

Dual‐function catalysis in propane dehydrogenation over Pt₁–Ga₂O₃ catalyst: Insights from a microkinetic analysis