Conversion of butanol to propene in flow: A triple dehydration, isomerisation and metathesis cascade

Shi, Yiping; Weller, Andrew S.; Blacker, A. John; Dyer, Philip W.

doi:10.1016/j.catcom.2022.106421

Cited by 5 publications

(3 citation statements)

References 32 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Accordingly, it should be possible to fit the results from this model to the kinetics for other catalysts. With some extensions, the microkinetic modeling strategy employed in this work may also yield useful models for other metathesis reactions with mixed macromolecular reactants. ,,,,, …”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

A Microkinetic Model for Isomerizing Ethenolysis

Chen,

Sadow,

Peters

2024

ACS Catal.

View full text Add to dashboard Cite

In isomerizing ethenolysis, tandem double bond isomerization and olefin metathesis catalysts convert polyethylene and ethylene coreactants into propylene. Isomerizing ethenolysis is particularly interesting among polymer upcycling strategies because of its potentially high selectivity to a specific valueadded product. Following a theoretical analysis by Guironnet and Peters [J. Phys. Chem. 124, 3935 (2020)], Conk et al. [Science, 377, 1561(2022] demonstrated isomerizing ethenolysis in experiments using an iridium pincer dehydrogenation catalyst, a dimeric Pd(I) bromide isomerization catalyst, and a second-generation Hoveyda−Grubbs metathesis catalyst. This paper compares model predictions to the two-stage dehydrogenation and isomerizing ethenolysis experiments of Conk et al. In a model that accounts for the initial dehydrogenation and subsequent evolution of the chain length distribution, we show that the experimental propylene generation rates are consistent with an isomerizing ethenolysis rate that is zeroth order in the concentration of long chain ends. In contrast, Guironnet and Peters assumed a first order dependence on chain ends. To understand the discrepancy, we developed and solved a microkinetic model for the isomerizing ethenolysis reaction. Rate parameters in the microkinetic model are estimated from prior experiments and known equilibria. We find that the experiments of Conk et al. are performed near conditions of the theoretical maximum propylene production rate, where the kinetics are saturated with respect to both chain end and ethylene concentrations. For long chains, not preshortened by initial dehydrogenation and ethenolysis steps as in Conk et al., the model predicts lowered chain end concentrations and smaller propylene production rates that can become inhibited by high ethylene pressure.

show abstract

Section: Discussionmentioning

confidence: 99%

“…With some extensions, the microkinetic modeling strategy employed in this work may also yield useful models for other metathesis reactions with mixed macromolecular reactants. 1,46,47,56,59,60 ■ ASSOCIATED CONTENT * sı Supporting Information…”

Section: ■ Conclusionmentioning

confidence: 99%

A Microkinetic Model for Isomerizing Ethenolysis

Chen,

Sadow,

Peters

2024

ACS Catal.

View full text Add to dashboard Cite

show abstract

“…[88][89][90] Zeolites are most widely implemented in FCC, but they are also very active for dehydration reactions, [91][92][93] particularly the dehydration of methanol to give olefins. 94 ZSM-5 has often been identified as the catalyst of choice for a variety of alcohol dehydrations due to its good performance at lower reaction temperatures (for example, ZSM-5 was found to be more active for ethanol dehydration at lower temperatures than alumina or silica containing 13 wt% alumina), 69 and with higher alkene yields, 25,30,93,[95][96][97][98][99][100] but stability is an issue. 96,101 Balancing activity, stability and selectivity with other factors, such as nature of the alcohol, can lead to other zeolites being favoured, such as H-MOR (mordenite) 69,95 or silicoaluminophosphates, such as SAPO-34.…”

Section: Zeolitesmentioning

confidence: 99%