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Calvin H. Bartholomew - One of the best experts on this subject based on the ideXlab platform.

  • heterogeneous catalyst Deactivation and regeneration a review
    Catalysts, 2015
    Co-Authors: Morris D Argyle, Calvin H. Bartholomew
    Abstract:

    Deactivation of heterogeneous catalysts is a ubiquitous problem that causes loss of catalytic rate with time. This review on Deactivation and regeneration of heterogeneous catalysts classifies Deactivation by type (chemical, thermal, and mechanical) and by mechanism (poisoning, fouling, thermal degradation, vapor formation, vapor-solid and solid-solid reactions, and attrition/crushing). The key features and considerations for each of these Deactivation types is reviewed in detail with reference to the latest literature reports in these areas. Two case studies on the Deactivation mechanisms of catalysts used for cobalt Fischer-Tropsch and selective catalytic reduction are considered to provide additional depth in the topics of sintering, coking, poisoning, and fouling. Regeneration considerations and options are also briefly discussed for each Deactivation mechanism.

  • mechanisms of catalyst Deactivation
    Applied Catalysis A-general, 2001
    Co-Authors: Calvin H. Bartholomew
    Abstract:

    Abstract The literature treating mechanisms of catalyst Deactivation is reviewed. Intrinsic mechanisms of catalyst Deactivation are many; nevertheless, they can be classified into six distinct types: (i) poisoning, (ii) fouling, (iii) thermal degradation, (iv) vapor compound formation accompanied by transport, (v) vapor-solid and/or solid-solid reactions, and (vi) attrition/crushing. As (i), (iv), and (v) are chemical in nature and (ii) and (v) are mechanical, the causes of Deactivation are basically three-fold: chemical, mechanical and thermal. Each of these six mechanisms is defined and its features are illustrated by data and examples from the literature. The status of knowledge and needs for further work are also summarized for each type of Deactivation mechanism. The development during the past two decades of more sophisticated surface spectroscopies and powerful computer technologies provides opportunities for obtaining substantially better understanding of Deactivation mechanisms and building this understanding into comprehensive mathematical models that will enable more effective design and optimization of processes involving deactivating catalysts.

  • Mechanisms of catalyst Deactivation
    Applied Catalysis A-general, 2001
    Co-Authors: Calvin H. Bartholomew
    Abstract:

    The literature treating mechanisms of catalyst Deactivation is reviewed. Intrinsic mechanisms of catalyst Deactivation are many; nevertheless, they can be classified into six distinct types: (i) poisoning, (ii) fouling, (iii) thermal degradation, (iv) vapor compound formation accompanied by transport, (v) vapor-solid and/or solid-solid reactions, and (vi) attrition/crushing. As (i), (iv), and (v) are chemical in nature and (ii) and (v) are mechanical, the causes of Deactivation are basically three-fold: chemical, mechanical and thermal. Each of these six mechanisms is defined and its features are illustrated by data and examples from the literature. The status of knowledge and needs for further work are also summarized for each type of Deactivation mechanism. The development during the past two decades of more sophisticated surface spectroscopies and powerful computer technologies provides opportunities for obtaining substantially better understanding of Deactivation mechanisms and building this understanding into comprehensive mathematical models that will enable more effective design and optimization of processes involving deactivating catalysts. © 2001 Elsevier Science B.V. All rights reserved.

  • Catalyst Deactivation 1997 : proceedings of the international symposium, Cancun, Mexico, October 5-8, 1997
    1997
    Co-Authors: Calvin H. Bartholomew, G. A. Fuentes
    Abstract:

    Part 1 Review articles (plenary and award lectures): roles of acidity and pore structure in the Deactivation of zeolites by carbonaceous deposits, M. Guisnet et al impact of sulfur on three-way automotive catalyst performance and catalyst diagnostics, D.D. Beck. Part 2 Topical articles (oral and poster presentations) - carbon deposition and coking: the relationship between metal particle morphology and the structural characteristics of carbon deposits, R.T.K. Baker et al self-poisoning and aging of Pd-Ag/Al1,O3 in semi-hydrogenation of 1,3-butadiene - effects of surface inhomogeneity caused by hydrocarbonaceous deposits, A. Sarkany. Part 3 Chemicals: the role of coke deposition in the conversion of methanol to olefins over SAPO-34, D. Chen et al Deactivation and regeneration of alkane dehydrogenation catalysts, S.D. Jackson et al a novel mechanism of catalyst Deactivation in liquid phase synthesis gas-to DME reactions, X.D. Peng et al. Part 4 Environmental: sulfur tolerance of Cu- and H-mordenite zeolite catalysts for the reduction of NO by hydrocarbons, M.H. Kim et al Deactivation of Cu-ZSM-5 during selective catalytic reduction of NO by propane under wet conditions, A. Martinez et al H-mordenite Deactivation during the SCR of NOx, adsorption and diffusion of probe molecules on fresh and deactivated catalysts, E.E. Miro et al. Part 5 Modelling and kinetic studies: coke Deactivation of hydrotreating catalysts - a variable site model, F.E. Massoth coke formation in fluid catalytic cracking, M.A. den Hollander et al. Part 6 Petroleum: effects of the metal-metal interactions on the stability of Pt-Re/Al2O3-Cl reforming catalysts, J. Barbier et al temperature programmed oxidation of deactivated Pt/Nb2O5 catalysts, D.A.G. Aranda et al effects of sulfidation of Mo nitride and CoMo nitride catalysis on thiopene HDS, S.-K. Ihm et al catalyst Deactivation by metals and coke during hydrodemetallation, M. Nunez et al Deactivation of Pt-Sn/Al2O3 catalysts by coking - influence of the preparation method, G. Corro et al new developments in FCC catalyst Deactivation by metals - metals mobility and the vanadium mobility index (VMI), L.T. Broock et al stability of an FCC catalyst matrix for processing gas oil with resid, P. Gamero et al. Part 7 Poisoning: industrial evaluation of selective hydrogenation catalyst poisoning, B. Didillon et al the mechanism of metal poisoning by cyclic Deactivation in fluid cracking catalysts, F. Hernandez et al AFM and XPS studies of thiophene and 1-butanethiol Deactivation of Pd/Al2O3 model catalysts during 1,3-butanethiol hydrogenation, K.-H. Lee et al. Part 8 Syngas conversion: Deactivation and attrition of iron catalysts in synthesis gas, N.B. Jackson et al temperature-programmed reaction study of carbon transformations on iron Fischer-Tropsch catalysts during steady-state synthesis, S.A. Eliason and C.H. Bartholomew. (Part contents)

Kimio Ariyoshi - One of the best experts on this subject based on the ideXlab platform.

  • Deactivation and regeneration of ethylenimine production catalyst
    Applied Catalysis A: General, 2007
    Co-Authors: Hideaki Tsuneki, Kimio Ariyoshi
    Abstract:

    We studied the Deactivation of silica-alkaline-phosphate catalyst for ethylenimine production by vapor phase intramolecular dehydration of monoethanolamine. There are two types of catalyst Deactivation-a short time-range Deactivation caused by coking and a long time-range Deactivation due to structural changes in the catalyst such as sintering or loss of active component. Catalytic activity decreases along with lowering of the surface area when sintering occurs. Sintering is accelerated by water vapor at high temperature. Loss of phosphorus, which is one of the catalytically active components, also causes Deactivation. The lost phosphorus in the catalyst can be resupplied by treatment with volatile phosphorus compounds in the reactor, and catalytic activity and selectivity can be recovered. © 2007 Elsevier B.V. All rights reserved.

  • Deactivation and regeneration of ethylenimine production catalyst
    Applied Catalysis A-general, 2007
    Co-Authors: Hideaki Tsuneki, Kimio Ariyoshi
    Abstract:

    Abstract We studied the Deactivation of silica–alkaline-phosphate catalyst for ethylenimine production by vapor phase intramolecular dehydration of monoethanolamine. There are two types of catalyst Deactivation—a short time-range Deactivation caused by coking and a long time-range Deactivation due to structural changes in the catalyst such as sintering or loss of active component. Catalytic activity decreases along with lowering of the surface area when sintering occurs. Sintering is accelerated by water vapor at high temperature. Loss of phosphorus, which is one of the catalytically active components, also causes Deactivation. The lost phosphorus in the catalyst can be resupplied by treatment with volatile phosphorus compounds in the reactor, and catalytic activity and selectivity can be recovered.

Ramoa F Ribeiro - One of the best experts on this subject based on the ideXlab platform.

  • Deactivation of fcc catalysts
    Journal of Molecular Catalysis A-chemical, 2008
    Co-Authors: Henrique S Cerqueira, G Caeiro, L Costa, Ramoa F Ribeiro
    Abstract:

    Over the course of the commercial fluid catalytic cracking (FCC), catalyst Deactivation occurs both reversibly, as a result of side reactions that eventually yields coke, and irreversibly, due to contaminants present in the feedstock or to the dealumination of the zeolite catalyst component. Herein, we discuss the Deactivation of HY zeolite and FCC catalysts from a fundamental as well as an applied point of view. Aspects related to the various causes of FCC catalysts (and additives) Deactivation under industrial conditions are also summarized.

Freek Kapteijn - One of the best experts on this subject based on the ideXlab platform.

  • Handbook of Heterogeneous Catalysis - Deactivation and Regeneration
    Handbook of Heterogeneous Catalysis, 2008
    Co-Authors: Jacob A. Moulijn, Annelies E. Van Diepen, Freek Kapteijn
    Abstract:

    The sections in this article are Introduction Causes of Deactivation Poisoning Formation of Deposits Thermal Degradation Mechanical Deactivation Corrosion/Leaching Stability Too Low: What To Do? Measures on the Scale of the Catalyst Particle Tailored Reactor and Process Design Relation Between Time-Scale of Deactivation and Choice of Reactor Chemical Reaction Engineering Solutions Allowing for Regeneration Good Engineering Practice Feed Purification Optimizing Reaction Conditions Optimal Conditions as a Function of Time-on-Stream Regeneration or Replacement of the Catalyst Poisoning Deposits Sintering Leaching Conclusion Keywords: Deactivation; regeneration; poisoning; thermal degradation

  • catalyst Deactivation is it predictable what to do
    Applied Catalysis A-general, 2001
    Co-Authors: Jacob A. Moulijn, A E Van Diepen, Freek Kapteijn
    Abstract:

    Abstract Catalyst Deactivation is usually inevitable, although the rate at which it occurs varies greatly. This article discusses the causes of Deactivation and the influence on reaction rate. Methods for minimising catalyst Deactivation, by tailoring catalyst properties and/or process operations, are presented, as well as reactor configurations suitable for the regeneration of deactivated catalysts. Alkane dehydrogenation is used as an example to demonstrate the variety of engineering solutions possible.

  • Catalyst Deactivation: is it predictable?: What to do?
    Applied Catalysis A-general, 2001
    Co-Authors: Jacob A. Moulijn, A E Van Diepen, Freek Kapteijn
    Abstract:

    Abstract Catalyst Deactivation is usually inevitable, although the rate at which it occurs varies greatly. This article discusses the causes of Deactivation and the influence on reaction rate. Methods for minimising catalyst Deactivation, by tailoring catalyst properties and/or process operations, are presented, as well as reactor configurations suitable for the regeneration of deactivated catalysts. Alkane dehydrogenation is used as an example to demonstrate the variety of engineering solutions possible.

Jacob A. Moulijn - One of the best experts on this subject based on the ideXlab platform.

  • Handbook of Heterogeneous Catalysis - Deactivation and Regeneration
    Handbook of Heterogeneous Catalysis, 2008
    Co-Authors: Jacob A. Moulijn, Annelies E. Van Diepen, Freek Kapteijn
    Abstract:

    The sections in this article are Introduction Causes of Deactivation Poisoning Formation of Deposits Thermal Degradation Mechanical Deactivation Corrosion/Leaching Stability Too Low: What To Do? Measures on the Scale of the Catalyst Particle Tailored Reactor and Process Design Relation Between Time-Scale of Deactivation and Choice of Reactor Chemical Reaction Engineering Solutions Allowing for Regeneration Good Engineering Practice Feed Purification Optimizing Reaction Conditions Optimal Conditions as a Function of Time-on-Stream Regeneration or Replacement of the Catalyst Poisoning Deposits Sintering Leaching Conclusion Keywords: Deactivation; regeneration; poisoning; thermal degradation

  • catalyst Deactivation is it predictable what to do
    Applied Catalysis A-general, 2001
    Co-Authors: Jacob A. Moulijn, A E Van Diepen, Freek Kapteijn
    Abstract:

    Abstract Catalyst Deactivation is usually inevitable, although the rate at which it occurs varies greatly. This article discusses the causes of Deactivation and the influence on reaction rate. Methods for minimising catalyst Deactivation, by tailoring catalyst properties and/or process operations, are presented, as well as reactor configurations suitable for the regeneration of deactivated catalysts. Alkane dehydrogenation is used as an example to demonstrate the variety of engineering solutions possible.

  • Catalyst Deactivation: is it predictable?: What to do?
    Applied Catalysis A-general, 2001
    Co-Authors: Jacob A. Moulijn, A E Van Diepen, Freek Kapteijn
    Abstract:

    Abstract Catalyst Deactivation is usually inevitable, although the rate at which it occurs varies greatly. This article discusses the causes of Deactivation and the influence on reaction rate. Methods for minimising catalyst Deactivation, by tailoring catalyst properties and/or process operations, are presented, as well as reactor configurations suitable for the regeneration of deactivated catalysts. Alkane dehydrogenation is used as an example to demonstrate the variety of engineering solutions possible.

  • Catalyst testing and Deactivation in hydrometallization
    Preprints-American Chemical Society Division of Petroleum Chemistry, 1995
    Co-Authors: J.p. Janssens, A.d. Van Langeveld, Jacob A. Moulijn
    Abstract:

    Metal deposition causes irreversible catalyst Deactivation in heavy oil processing. The Deactivation process is determined by reaction kinetics, diffusion and the (changing) catalyst porous texture, all linked together in mass balances. In this paper, experimental results on catalyst Deactivation and hydrodemetallization reaction kinetics are presented and discussed