Mass transfer and influence of the local catalyst activity on the conversion in a riser reactor

R.H. Venderbosch, W. Prins, Willibrordus Petrus Maria van Swaaij

Research output: Contribution to journalArticleAcademicpeer-review

18 Citations (Scopus)

Abstract

Gas-solids contacting in risers has been studied based on measurements of mass transfer controlled CO oxidation over a Pt/γ-alumina catalyst, and on experimental results published by Ouyang et al. (1995) for the kinetically controlled ozone decomposition. In the present experiments, the catalyst activity was varied by mixing the active catalyst particles with similar, but inert γ-alumina particles (in ratios from 150 to 2500 m3inert/m3cat), whereas Ouyang and co-workers varied the operating temperature (de 300 à to 500 K). Mass transfer controlled CO oxidation occurs at temperatures above 750 K. A negative square root dependency has been observed for the relationship between the Sherwood number and the solid hold-up. Increasing the gas velocity always improves the gas-solids contacting. The local catalyst activity appears to be an important parameter. As an important conclusion of the present work, it can be stated that at a high local activity, the conversion rate per unit volume of catalyst decreases significantly due to local depletion of reactant.
Original languageUndefined
Pages (from-to)262-274
Number of pages13
JournalCanadian journal of chemical engineering
Volume77
Issue number2
DOIs
Publication statusPublished - 1999

Keywords

  • gas-solids contacting
  • carbon monoxide oxidation
  • clusters
  • METIS-240672
  • IR-71489
  • Mass transfer
  • riser

Cite this

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title = "Mass transfer and influence of the local catalyst activity on the conversion in a riser reactor",
abstract = "Gas-solids contacting in risers has been studied based on measurements of mass transfer controlled CO oxidation over a Pt/γ-alumina catalyst, and on experimental results published by Ouyang et al. (1995) for the kinetically controlled ozone decomposition. In the present experiments, the catalyst activity was varied by mixing the active catalyst particles with similar, but inert γ-alumina particles (in ratios from 150 to 2500 m3inert/m3cat), whereas Ouyang and co-workers varied the operating temperature (de 300 {\`a} to 500 K). Mass transfer controlled CO oxidation occurs at temperatures above 750 K. A negative square root dependency has been observed for the relationship between the Sherwood number and the solid hold-up. Increasing the gas velocity always improves the gas-solids contacting. The local catalyst activity appears to be an important parameter. As an important conclusion of the present work, it can be stated that at a high local activity, the conversion rate per unit volume of catalyst decreases significantly due to local depletion of reactant.",
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Mass transfer and influence of the local catalyst activity on the conversion in a riser reactor. / Venderbosch, R.H.; Prins, W.; van Swaaij, Willibrordus Petrus Maria.

In: Canadian journal of chemical engineering, Vol. 77, No. 2, 1999, p. 262-274.

Research output: Contribution to journalArticleAcademicpeer-review

TY - JOUR

T1 - Mass transfer and influence of the local catalyst activity on the conversion in a riser reactor

AU - Venderbosch, R.H.

AU - Prins, W.

AU - van Swaaij, Willibrordus Petrus Maria

PY - 1999

Y1 - 1999

N2 - Gas-solids contacting in risers has been studied based on measurements of mass transfer controlled CO oxidation over a Pt/γ-alumina catalyst, and on experimental results published by Ouyang et al. (1995) for the kinetically controlled ozone decomposition. In the present experiments, the catalyst activity was varied by mixing the active catalyst particles with similar, but inert γ-alumina particles (in ratios from 150 to 2500 m3inert/m3cat), whereas Ouyang and co-workers varied the operating temperature (de 300 à to 500 K). Mass transfer controlled CO oxidation occurs at temperatures above 750 K. A negative square root dependency has been observed for the relationship between the Sherwood number and the solid hold-up. Increasing the gas velocity always improves the gas-solids contacting. The local catalyst activity appears to be an important parameter. As an important conclusion of the present work, it can be stated that at a high local activity, the conversion rate per unit volume of catalyst decreases significantly due to local depletion of reactant.

AB - Gas-solids contacting in risers has been studied based on measurements of mass transfer controlled CO oxidation over a Pt/γ-alumina catalyst, and on experimental results published by Ouyang et al. (1995) for the kinetically controlled ozone decomposition. In the present experiments, the catalyst activity was varied by mixing the active catalyst particles with similar, but inert γ-alumina particles (in ratios from 150 to 2500 m3inert/m3cat), whereas Ouyang and co-workers varied the operating temperature (de 300 à to 500 K). Mass transfer controlled CO oxidation occurs at temperatures above 750 K. A negative square root dependency has been observed for the relationship between the Sherwood number and the solid hold-up. Increasing the gas velocity always improves the gas-solids contacting. The local catalyst activity appears to be an important parameter. As an important conclusion of the present work, it can be stated that at a high local activity, the conversion rate per unit volume of catalyst decreases significantly due to local depletion of reactant.

KW - gas-solids contacting

KW - carbon monoxide oxidation

KW - clusters

KW - METIS-240672

KW - IR-71489

KW - Mass transfer

KW - riser

U2 - 10.1002/cjce.5450770211

DO - 10.1002/cjce.5450770211

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JO - Canadian journal of chemical engineering

JF - Canadian journal of chemical engineering

SN - 0008-4034

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