Physical Factors Affecting Hydrocarbon Oxidation in a Diesel Oxidation Catalyst

A study of factors affecting hydrocarbon oxidation in a diesel oxidation catalyst was undertaken. The objective was to determine whether interactions between particulate-adsorbed hydrocarbons and the catalyst significantly influenced hydrocarbon oxidation. Theoretical modeling supported by experimental data obtained at the U.S. Bureau of Mines` Diesel Emissions Research Laboratory indicated that the mass of particles interacting with the ceramic support was negligible. Additionally, a model of hydrocarbon adsorption onto diesel particulate predicted that over 98% by mass of exhaust hydrocarbons would be gas-phase, rather than particulate-adsorbed, at converter operating temperatures. A second physical process, the diffusion of gas phase hydrocarbon to the catalytic surface, was subsequently investigated. Theoretical and experimental results for the unburnt fuel hydrocarbons indicated that hydrocarbon oxidation was diffusion limited under high temperature operating conditions. 84 refs., 16 figs., 3 tabs.

[1]  B. T. Mcclure,et al.  The Influence of an Oxidation Catalytic Converter and Fuel Composition on the Chemical and Biological Characteristics of Diesel Exhaust Emissions , 1992 .

[2]  C. P. Yu,et al.  Deposition of charged particles from laminar flows in rectangular and cylindrical channels by image force , 1978 .

[3]  A. Mcfarland,et al.  Aerosol particle losses in isokinetic sampling probe inlets , 1992 .

[4]  A. Mcfarland,et al.  Aerosol penetration through a model transport system: Comparison of theory and experiment , 1991 .

[5]  C. P. Yu,et al.  Particle Deposition from Duct Flows by Combined Mechanisms , 1993 .

[6]  Helmut F. Bauer,et al.  Diffusion, convection and chemical reaction in a channel , 1976 .

[7]  David B. Kittelson,et al.  THE INFLUENCE OF A CERAMIC PARTICLE TRAP ON THE SIZE DISTRIBUTION OF DIESEL PARTICLES , 1985 .

[8]  C. N. Davies,et al.  The Mechanics of Aerosols , 1964 .

[9]  David L. Van Ostrom,et al.  A Three-Dimensional Model for the Analysis of Transient Thermal and Conversion Characteristics of Monolithic Catalytic Converters , 1988 .

[10]  J. M. Geist,et al.  Electronic Spray Analyzer for Electrically Conducting Particles , 1951 .

[11]  Steven L. Plee,et al.  SOME MECHANISMS AFFECTING THE MASS OF DIESEL EXHAUST PARTICULATE COLLECTED FOLLOWING A DILUTION PROCESS , 1980 .

[12]  George M. Homsy,et al.  Thermophoretic deposition of small particles in laminar tube flow , 1979 .

[13]  K L Rubow,et al.  Electrostatic effects in aerosol sampling and filtration. , 1985, The Annals of occupational hygiene.

[14]  D. Ingham.  Diffusion of aerosols from a stream flowing through a short cylindrical pipe , 1984 .

[15]  G. Andrews,et al.  Diesel Particulate SOF Emissions Reduction Using an Exhaust Catalyst , 1987 .

[16]  A. Myers,et al.  Effect of adsorption equation on prediction of multicomponent adsorption equilibria by the ideal adsorbed solution theory , 1989 .

[17]  A. Mersmann,et al.  Calculation methods for multicomponent adsorption equilibria , 1991 .

[18]  D R Hemenway,et al.  Use of physical chemistry and in vivo exposure to investigate the toxicity of formaldehyde bound to carbonaceous particles in the murine lung. , 1992, Research report.

[19]  D. Ingham.  Diffusion of aerosols in the entrance region of a smooth cylindrical pipe , 1991 .

[20]  G. Carey,et al.  Finite element analysis of mass transport through a viscous fluid with reaction , 1987 .

[21]  S. Sircar,et al.  Surface potential theory of multilayer adsorption from gas mixtures , 1973 .

[22]  A. Myers,et al.  Rapid calculations of multicomponent adsorption equilibria from pure isotherm data , 1985 .

[23]  F. Incropera,et al.  Fundamentals of Heat Transfer , 1981 .

[24]  Susan T. Bagley,et al.  Ceramic Particulate Traps for Diesel Emissions Control - Effects of a Manganese-Copper Fuel Additive , 1988 .

[25]  Sotiris E. Pratsinis,et al.  Particle coagulation, diffusion and thermophoresis in laminar tube flows , 1989 .

[26]  M. Horiuchi,et al.  Sulfur Storage and Discharge Behavior on Flow-Through Type Oxidation Catalysts , 1991 .

[27]  R. Shah.  Laminar Flow Forced convection in ducts , 1978 .

[28]  C. Pereira,et al.  Camet oxidation catalyst for cogeneration applications , 1991 .

[29]  John H. Johnson,et al.  The Measurement and Analysis of the Physical Character of Diesel Particulate Emissions , 1976 .

[30]  S. Bagley,et al.  The Effect of an Oxidation Catalyst on the Physical, Chemical, and Biological Character of Diesel Particulate Emissions , 1981 .

[31]  D. Kittelson,et al.  Methods for the selective sampling of diesel particulate in mine-dust aerosols. Open File Report, 27 August 1984-26 July 1986 , 1986 .

[32]  M. B. Ranade,et al.  Adhesion and Removal of Fine Particles on Surfaces , 1987 .

[33]  L. Schmidt,et al.  The role of boundary layer mass transfer in partial oxidation selectivity , 1992 .

[34]  D. Boulaud,et al.  Experimental study of thermophoretic particle deposition in laminar tube flow , 1991 .

[35]  A Computer Heat Transfer and Hydrocarbon Adsorption Model for Predicting Diesel Particulate Emissions in Dilution Tunnels , 1982 .

[36]  John H. Johnson,et al.  The Influence of Sampling Conditions on the Repeatability of Diesel Particulate and Vapor Phase Hydrocarbon and PAH Measurements , 1990 .

[37]  A. Myers,et al.  A comprehensive technique for equilibrium calculations in adsorbed mixtures: the generalized FastIAS method , 1988 .

[38]  David B. Kittelson,et al.  Variability in Particle Emission Measurements in the Heavy Duty Transient Test , 1991 .

[39]  J. Pich.  Theory of gravitational deposition of particles from laminar flows in channels , 1972 .

[40]  Frank Terres,et al.  Optimisation of Catalytic Converter Gas Flow Distribution by CFD Prediction , 1993 .

[41]  William B. Retallick,et al.  Operational Characteristics of a Double-Spiral Heat Exchanger for the Catalytic Incineration of Contaminated Air , 1990 .

[42]  W. O. Siegl,et al.  Improved Emissions Speciation Methodology for Phase II of the Auto/Oil Air Quality Improvement Research Program - Hydrocarbons and Oxygenates , 1993 .

[43]  B. Cooper,et al.  Role of NO in Diesel Particulate Emission Control , 1989 .

[44]  David B. Kittelson,et al.  Further studies of electrostatic collection and agglomeration of diesel particles , 1991 .

[45]  R. Schefer,et al.  Thermophoresis of particles in a heated boundary layer , 1980, Journal of Fluid Mechanics.

[46]  Ronald L. Bradow,et al.  CHARACTERIZATION OF HEAVY-DUTY DIESEL GASEOUS AND PARTICULATE EMISSIONS, AND EFFECTS OF FUEL COMPOSITION , 1979 .

[47]  D. Taulbee.  Simultaneous diffusion and sedimentation of aerosol particles from Poiseuille flow in a circular tube , 1978 .

[48]  G. Batchelor,et al.  Thermophoretic deposition of particles in gas flowing over cold surfaces , 1985 .

[49]  Frank Black,et al.  Methodology for Determining Particulate and Gaseous Diesel Hydrocarbon Emissions , 1979 .

[50]  Techniques for Diesel Emissions Measurement , 1968 .

[51]  F. Brear,et al.  The Role of the Through Flow Oxidation Catalyst in the Development of a Low Emissions Specification HD Diesel Engine , 1992 .

[52]  H. Arai,et al.  Recent progress in high-temperature catalytic combustion , 1991 .

[53]  Marty A. Barris.  Development of Diesel Exhaust Catalytic Converter Mufflers , 1992 .

[54]  Kyriacos Zygourakis,et al.  Transient operation of monolith catalytic converters: a two-dimensional reactor model and the effects of radially nonuniform flow distributions , 1989 .

[55]  Paul T. Williams,et al.  The Role of Exhaust Pipe and Incylinder Deposits on Diesel Particulate Composition , 1992 .

[56]  S. Ozturk,et al.  International Experience Using Diesel Catalytic Converters for Urban Buses , 1994 .

[57]  S. Ross,et al.  On Physical Adsorption , 1964 .

[58]  Marty A. Barris,et al.  The Influence of Lubricating Oil and Diesel Fuel on Ash Accumulation in an Exhaust Particulate Trap , 1991 .

[59]  V. Zagaynov,et al.  Deposition of aerosol particles in plane-parallel channels at different wall temperatures , 1990 .

[60]  John H. Johnson,et al.  Effects of an Oxidation Catalytic Converter on Regulated and Unregulated Diesel Emissions , 1994 .