Chemical and Biomolecular Engineering

Top 20 Doctoral Program — National Research Council


Dr. Michael P. Harold
Dr. Michael P. Harold

Chair of Chemical and Biomolecular Engineering;
M.D. Anderson Professor of Chemical and Biomolecular Engineering

Office Location: S225, Engineering Building 1
Phone: 713-743-4322   |   Fax: 713-743-4323
Email: mharold [at] uh [dot] edu
Harold's research


B.S., Chemical Engineering, Pennsylvania State University, (1980)
Ph.D., Chemical Engineering, University of Houston, (1985)


Michael P. Harold received his B.S. in Chemical Engineering from Penn State in 1980 and his PhD in Chemical Engineering from the University of Houston in 1985. Mike joined the faculty of the Chemical Engineering Department at the University of Massachusetts at Amherst, where he became Associate Professor in 1991. In 1991 Mike was a Visiting Research Scholar at the Chemical Technology Department of University of Twente in Enschede, the Netherlands. In 1993 Mike joined DuPont Company where he held several research and supervisory positions. In 1999 Mike was appointed Research Manager of the Chemical Process Fundamentals Group in the Central Research Department of the DuPont Company. While at DuPont Mike was Adjunct Professor at the University of Delaware and was Chair of the Catalysis and Reaction Engineering Division of AIChE. In his R&D supervisory roles at DuPont Mike led programs to develop breakthrough technologies for the manufacture of key industrial polymers and their corresponding chemical intermediates, and synthetic melt-spun fibers. Mike then moved back to academia as chair of the UH Department of Chemical Engineering, which later became the Department of Chemical and Biomolecular Engineering. He served this post until fall 2008.

Mike’s research expertise and interests are in the area of chemical reaction engineering, with specific focus on reaction-separation devices, inorganic membrane synthesis and applications, and catalytic and biocatalytic materials. Mike has 90 refereed publications, over 100 presentations at technical conferences, and over 60 invited seminars and lectures.

Research Interests: 

Over the past two decades spanning academia and industry, Dr. Harold has coupled probing experiments with predictive models to elucidate the interactions of reaction and transport processes in catalytic reactors. He has advanced the understanding of multi-functional reactors and their use in energy and environmental applications, including the membrane reactor for coupled hydrogen generation and purification, and the adsorptive reactor for lean NOx reduction. His pioneering research has helped to reduce byproduct formation, to improve reactor safety, and to intensify the overall chemical process. Areas of particular interest include reaction-separation devices and materials, catalytic reaction engineering, and combustion processes. Ongoing projects include:


Our nation's most crucial energy challenge is in finding new sources of liquid fuels for transportation. Aquatic biomass is a potential vast, renewable source of liquid fuel.  For example, algae can be grown at high rates on non-arable lands, both in fresh and salt water.  While some strains of algae are edible, it's use for energy does not pose an ethical dilemma. The overarching goal of this research is to advance the knowledge and understanding of catalytic pyrolysis of microalgae into a stabilized liquid that has an acceptable energy content and composition for downstream processing with conventional petroleum refining. The working hypothesis of our research is that algal biomass can be converted into a stable liquid product through a single step catalytic reductive pyrolysis.  Our objectives are to

(i)     understand the effect of reductants on the noncatalytic pyrolysis of model carbohydrates, proteins, and lipids.
(ii)    quantify the effects of metal exchanged zeolite catalysts on the reductive pyrolysis of model compounds.
(iii)   apply the knowledge gained in the model compound studies to whole algae.
(iv)    converge to prescribed performance targets in terms of oxygen content, chemical stability, and sustained catalytic activity.

To achieve these objectives we are applying catalytic reaction engineering tools, with a particular focus on the discovery and development of new catalytic materials and design of new reactors that convert the algal biomass.

High Temperature Inorganic Membrane Reactors

Traditionally, reactors have been designed and operated as stand-alone units, with heat exchange and separations carried out in parallel or sequentially. Our interest is to consolidate these functions into a single, multi-functional device in order to improve performance and reduce cost. Membrane reactors, selective product removal afford considerable improvements in desired product yield. The challenge is tailoring the membrane and catalyst for the reaction system of interest.

High Purity Hydrogen Generation for Fuel Cells

A specific application of membrane reactors is in the generation of high purity hydrogen from liquid fuels, which is critical for the widespread deployment of proton exchange membrane (PEM) fuel cells. Current fuel-to-hydrogen conversion technologies involves cumbersome sequences of independent steps, adding undesirable weight, volume, and complexity. We are evaluating the feasibility of a reaction and separation device for converting fuels into high purity hydrogen in a single step. The concept involves a membrane reactor in which hydrogen generation through fuel reforming and selective hydrogen separation are carried out simultaneously. Membrane synthesis, membrane reactor operation, and mathematical modeling are being carried out to evaluate the potential of the concept.

NOx Reduction in Lean Burn Engine Exhaust

We are investigating the catalytic reduction of NOx to nitrogen in the oxidizing atmosphere of lean burn and diesel vehicles. One approach involves the use of an adsorptive reactor in which the NOx is trapped as a nitrite/nitrate on an rare earth oxide and then reduced by the intermittent feed of a reductant. This is a complex system involving the abatement of a key pollutant contained in a time-varying feed utilizing a periodic catalytic process. The challenge is to achieve high NOx conversion with minimal fuel penalty while sustaining long catalyst life. We are carrying out bench-scale reactor and transient kinetics studies, microkinetic mechanisticbased modeling, and reactor modeling and simulations to determine optimal reactor designs, catalyst formulations, and operating strategies.

Integrated Catalytic Filtration Devices for Diesel Exhaust Abatement

In response to aggressive new emission standards, we are developing new technology for reducing particulates and NOx in the net-oxidizing exhaust of lean burn gasoline and diesel vehicles. One concept involves a transient-operated device with particulate filtration, NOx adsorptive storage, and NOx catalytic reduction to nitrogen. Our research involves the synthesis and evaluation of sorbents and catalysts, design and testing of devices, and optimization of the operating scheme. Transient catalytic studies are carried out to elucidate the capture and release of NOx, and the subsequent NOx reduction. We are investigating the use of diesel fuel as both a NOx desorption agent and chemical reductant, as well as simultaneous NOx release and soot oxidation.

Multiphase Selective Oxidation of Hydrocarbons

Selective oxidations of liquid hydrocarbons are particularly challenging due to exothermicity, flammability hazards, complex chemistry and multiphase contacting issues. Environmental and economic factors are increasing the need for higher oxygenate selectivity, improved reactor productivity and modularity, as well as lower investment and cost of manufacture. We are interested in elucidating the interactions of the free radical chemistry and transport phenomena, and in developing operating schemes that optimize the contacting of hydrocarbon and oxygen.

Schematic comparing synthesis of encapsulated Pd membrane with conventional toplayer membrane

Awards & Honors: 

2010–Present: Member, Industrial Engineering Chemistry Research Editorial Board
2010: Honda Initiation Grant Award, Honda Research Institute, “Enhancing Liquid Fuel Yield During Algae Pyrolysis in Structured Catalytic Reactors, “ (5 awarded out of 261) (2010).
2010: Fluor-Daniel Faculty Excellence Award, Cullen College of Engineering
2010: Outstanding Teaching Award, Cullen College of Engineering (2010).
2010: Abraham Dukler Distinguished Faculty Award, University of Houston, Engineering Alumni Association (2009).
2009-Present: Member, AIChE Chemical Technology Operating Council
2009-Present: Member, AIChE Journal Consulting Editor
2008: ACS Fuel Division Richard A. Glenn Award for the Best Paper presented at ACS 2007 National Meeting in Division of Fuel Chemistry (first out of 285 papers); Paper: “Hydrogen Generation and Purification in Pd Nanopore Hollow Fiber Membrane Reactor,” Authors: M. P. Harold and S. H. Israni
2008: Senior Faculty Research Excellence Award, Cullen College of Engineering, University of Houston
2007: Best Applied Paper Award – Southwest Section of AIChE: Lattner, J.R., and M.P. Harold, “Autothermal Reforming of Methanol: Experiments and Modeling, Catalysis Today, 120, 78-89 (2007).
2005–2008: Chair, AIChE Publication Committee
1999: Best Applied Paper award, Southwest Section of AIChE
1999: Chair, Catalysis and Reaction Engineering Division of AIChE
1999: Invited Participant in National Academy of Engineerin “Frontiers of Engineering Symposium”
1997–2000: Research Management, DuPont Company
1991: Visiting Research Fellow, University of Twente, The Netherlands
1990: Outstanding Junior Faculty Award, College of Engineering, University of Massachusetts

Selected Publications

  1. Bugosh, G., V. Easterling, and M.P. Harold,

    “Anomalous Steady-State and Spatio-Temporal Features of Methane Oxidation on Pt/Pd/Al2O3 Monolith Spanning Lean and Rich Conditions,” Applied Catalysis B. Environmental, 165, 68-78

    , 2015
  2. Shrestha, S., M.P. Harold, and K. Kamasamudram,

    “Experimental and Modeling Study of Selective Ammonia Oxidation on Multi-Functional Washcoated Monolith Catalysts,” Chem. Eng. Journal, 278, 24-35

    , 2015
  3. Perng, C., V. Easterling, and M.P. Harold,

    “Fast Lean-Rich Cycling for Enhanced NOx Conversion on Storage and Reduction Catalysts,” Catalysis Today, 231, 125-134

    , 2014
  4. Metkar, P.S., M.P. Harold, and V. Balakotaiah,

    “Kinetic Model of NH3-Based Selective Catalytic Reduction of NOx on Fe-ZSM-5 and Cu-Chabazite, and Dual Layer Fe/Cu Zeolitic Monolithic Catalysts,” Chem. Engin. Sci., 87, 51–66

    , 2013
  5. Shrestha, S., M.P. Harold, K. Kamasamudram, and A. Yezerets,

    “Ammonia Oxidation on Structured Composite Catalysts,” Topics in Catalysis, DOI 10.1007/s11244-013-9949-9

    , 2013
  6. Campanella, A., and M.P. Harold,

    “Pyrolysis of Microalgae and Duckweed in a Falling Solids Reactor:  Effects of Process Variables and Zeolite Catalysts,” J. Biomass and Bioenergy, 46, 218-232

    , 2012
  7. Bugosh, G. S.; Muncrief, R. L.; Harold, M. P.,

    Emission Analysis of Alternative Diesel Fuels Using a Compression Ignition Benchtop Engine Generator. Energy & Fuels 2011, 25 (10), 4704-4712.

    , 2011
  8. Israni, S. H.; Harold, M. P.,

    Methanol steam reforming in single-fiber packed bed Pd-Ag membrane reactor: Experiments and modeling. Journal of Membrane Science 2011, 369 (1-2), 375-387.

    , 2011
  9. Joshi, S. Y.; Ren, Y. J.; Harold, M. P.; Balakotaiah, V.,

    Determination of kinetics and controlling regimes for H(2) oxidation on Pt/Al(2)O(3) monolithic catalyst using high space velocity experiments. Applied Catalysis B-Environmental 2011, 102 (3-4), 484-495.

    , 2011
  10. Kumar, A.; Zheng, X. L.; Harold, M. P.; Balakotaiah, V.,

    Microkinetic modeling of the NO + H(2) system on Pt/Al(2)O(3) catalyst using temporal analysis of products. Journal of Catalysis 2011, 279 (1), 12-26.

    , 2011
  11. Liu, Y.; Harold, M. P.; Luss, D.,

    Spatio-temporal features of periodic oxidation of H(2) and CO on Pt/CeO(2)/Al(2)O(3). Applied Catalysis a-General 2011, 397 (1-2), 35-45.

    , 2011
  12. Meisami-Azad, M.; Mohammadpour, J.; Grigoriadis, K. M.; Harold, M. P.; Franchek, M. A.,

    Ieee, PCA-based Linear Parameter Varying Control of SCR Aftertreatment Systems. In 2011 American Control Conference, Ieee: New York, 2011.

    , 2011
  13. Metkar, P. S.; Balakotaiah, V.; Harold, M. P.,

    Experimental study of mass transfer limitations in Fe- and Cu-zeolite-based NH(3)-SCR monolithic catalysts. Chemical Engineering Science 2011, 66 (21), 5192-5203.

    , 2011
  14. Metkar, P. S.; Salazar, N.; Muncrief, R.; Balakotaiah, V.; Harold, M. P.,

    Selective catalytic reduction of NO with NH(3) on iron zeolite monolithic catalysts: Steady-state and transient kinetics. Applied Catalysis B-Environmental 2011, 104 (1-2), 110-126.

    , 2011
  15. Ren, Y. J.; Harold, M. P.,

    NO(x) Storage and Reduction with H(2) on Pt/Rh/BaO/CeO(2): Effects of Rh and CeO(2) in the Absence and Presence of CO(2) and H(2)O. Acs Catalysis 2011, 1 (8), 969-988.

    , 2011
  16. Xu, J.; Harold, M. P.; Balakotaiah, V.,

    Modeling the effects of Pt loading on NOx storage on Pt/BaO/Al(2)O(3) catalysts. Applied Catalysis B-Environmental 2011, 104 (3-4), 305-315.

    , 2011
  17. An, H., R. Muncrief, M.P. Harold, and H. Ismail,

    “Fast Screening of Alternative Diesel Fuels and Additives for NOx Reduction,” SAE Journal2010-01-1293

    , 2010
  18. Bhatia, D., R.D. Clayton, V. Balakotaiah, and M.P. Harold,

    “Modeling the Effect of Pt Dispersion and Temperature During Anaerobic Regeneration of a Lean NOx Trap Catalyst,”Catalysis Today151, 314–329

    , 2010
  19. Israni, S., and M.P. Harold,

    “Methanol steam reforming in Pd-based membrane reactors: Effects of reaction system species on hydrogen flux through a Pd-Ag membrane,” I&EC Research, accepted for publication, 10.1021/ie1005178

    , 2010
  20. Joshi, S., M.P. Harold, and V. Balakotaiah,

    “Overall Mass Transfer Coefficients and Controlling Regimes in Catalytic Monoliths,” Chem. Eng. Sci.65, 1729-1747

    , 2010
  21. Kumar, A., M.P. Harold, and V. Balakotaiah,

    “Estimation of Stored NOx Diffusion Coefficient in NOx Storage and Reduction,” I&EC Research, 10.1021/ie100504q

    , 2010
  22. Kumar, A., M.P. Harold, and V. Balakotaiah,

    “Isotopic TAP Studies of NO Decomposition and Reduction on Pt/BaO/Al2O3 Catalysts,” J. Catalysis, doi:10.1016/j.jcat.2009.12.018

    , 2010
  23. Bhatia, D., R.D. Clayton, M.P. Harold, and V. Balakotaiah,

    “A Global Kinetic Model for NOx Storage and Reduction on Pt/BaO/Al2O3 Monolithic Catalysts,” Catalysis Today147S, S250-S256

    , 2009
  24. Bhatia, D., V. Balakotaiah and M.P. Harold,

    “Bifurcation Analysis of CO and H2 Oxidation on Pt/Al2O3 Monolith Reactors.” Chem. Eng. Sci.64, 1544-1558

    , 2009
  25. Bhatia, D., V. Balakotaiah, M.P. Harold, and R. McCabe,

    “Experimental and Kinetic Study of NO Oxidation on Model Pt Catalysts,” J. Catalysis266, 106-119

    , 2009
  26. Clayton, R.D., M.P. Harold, and V. Balakotaiah,

    “Performance Features of Pt/BaO Lean NOx Trap with Hydrogen as Reductant,” AIChE J.55, 687-700

    , 2009
  27. Clayton, R.D.., M.P. Harold, V. Balakotaiah, and C.Z. Wan,

    “Effect of Pt Dispersion on NOx Storage and Reduction in Pt/BaO/Al2O3 Catalyst,” Appl. Catal. B. Environmental90, 662-676

    , 2009
  28. Israni, S.H., B. Nair and M. P. Harold,

    “Hydrogen Generation and Purification in a Composite Pd Hollow Fiber Membrane Reactor: Experiments and Modeling,” Catalysis Today130, 299-311

    , 2009
  29. Joshi, S., M.P. Harold, and V. Balakotaiah,

    “On the Use of External and Internal Mass Transfer Coefficients in the Transient Modeling of Catalytic Monolith Reactors,” Chemical Engineering Science64,  4976 - 4991

    , 2009
  30. Joshi, S., V. Balakotaiah, and M.P. Harold,

    “Low Dimensional Models for Real Time Simulation of Catalytic Monoliths,” AIChE J.55, 1771-1783

    , 2009
  31. Kumar, A., V. Medhekar, M.P. Harold, and V. Balakotaiah,

    “NO Decomposition and Reduction on Pt/Al2O3 Powder and Monolith Catalysts Using the TAP Reactor,” Appl. Catal. B. Environmental90, 642-651

    , 2009
  32. Xu, J., M.P. Harold, and V. Balakotaiah,

    “Microkinetic Modeling of Steady-State NO/H2/O2 on Pt/BaO/Al2O3 Monolith Catalysts,” Appl. Catal. B. Environmental89, 73-86

    , 2009
  33. Clayton, R.D., M.P. Harold, and V. Balakotaiah,

    “NOx Storage and Reduction with H2 on Pt/BaO/Al2O3 Monolith:  Spatio-Temporal Resolution of Product Distribution,” Appl. Catal. B. Environmental84, 616-630

    , 2008
  34. Clayton, R.D., M.P. Harold, and V. Balakotaiah,

    “Selective Catalytic Reduction of NO by H2 in O2 on Pt/BaO/Al2O3 Monolith NOx Storage Catalysts,” Appl. Catal. B. Environmental,81, 161-181

    , 2008
  35. Muncrief, R.L., C.W. Rooks, M.P. Harold, and M. Cruz,

    “Combining Biodiesel and Exhaust Gas Recirculation for Reduction in NOx and Particulate Emissions,” Energy and Fuels22, 1285-1296

    , 2008
  36. Nair, B., and M.P. Harold,

    “Experiments and Modeling of Transport in Composite Pd and Pd/Ag Coated Alumina Hollow Fibers,” J. Membrane Sci.311, 53-67

    , 2008
  37. Xu, J., R.D. Clayton, V. Balakotaiah, and M.P. Harold,

    “Experimental and Microkinetic Modeling of Steady-State NO Reduction by H2 on Pt/BaO/Al¬2O3 Monolith Catalysts,”Appl. Catal. B. Environmental77, 395-408

    , 2008
  38. Lattner, J.R., and M.P. Harold,

    “Autothermal Reforming of Methanol:  Experiments and Modeling,” Catalysis Today120, 78-89

    , 2007
  39. Medhekar, V., V. Balakotaiah, and M.P. Harold,

    “TAP Study of NOx Storage and Reduction on Pt/Al2O3 and Pt/Ba/Al2O3,” Catalysis Today121, 226-236

    , 2007
  40. Nair, B., and M.P. Harold,

    “Pd Encapsulated and Nanopore Hollow Fiber Membranes: Synthesis and Permeation Studies,” J. Membrane Sci.290, 182-195

    , 2007
  41. Nair, B., J. Choi, and M.P. Harold,

    “Electroless Plating and Permeation Features of Pd and Pd-Ag Hollow Fiber Composite Membranes,” J. Membrane Sci.288, 67-84

    , 2007
  42. Sharma, M., R.D. Clayton, M.P. Harold, and V. Balakotaiah,

    “Multiplicity in Lean NOx Traps,” Chem. Engng. Sci., Chem. Engng. Science62, 5176-5181

    , 2007
  43. Kabin, K., P. Khanna, R. Muncrief, V. Medhekar, and M.P. Harold,

    “Monolith and TAP Reactor Studies of NOX Storage on Pt/BaO/Al2O3: Elucidating the Mechanistic Pathways and Roles of Pt,” Catalysis Today114, 72-85

    , 2006
  44. Nair, B., and M.P. Harold,

    “Hydrogen Generation in a Pd Membrane Fuel Processor: Productivity Effects During Methanol Steam Reforming,” Chem. Engng. Science61, 6616-6636

    , 2006
  45. Su, Y., K. Kabin, M.P. Harold, and M.D. Amiridis,

    “Reactor and In-situ FTIR studies of Pt Pt/BaO/Al2O3 and Pd/BaO/Al2O3 NOx Storage and Reduction (NSR) Catalysts,” Appl. Catal. B. Environmental71, 207-215

    , 2006
  46. Theis, J., H.W. Jen, R. McCabe, M. Sharma, V. Balakotaiah, and M.P. Harold,

    “Reductive Elimination as a Mechanism for Purging a Lean NOx Trap,” Society of Automotive Engineers Journal, 2006-01-1067

    , 2006
  47. Lattner, J.R., and M.P. Harold,

    “Comparison of Methanol Based Fuel Processors for PEM Fuel Cell Systems,” Appl. Catalysis B. Environmental56, 149-169

    , 2005
  48. Sharma, M., K. Kabin, M.P. Harold, and V. Balakotaiah,

    “Modeling of NOx Storage and Reduction for Diesel Exhaust Emission Control,” Society of Automotive Engineers Journal, OFL-125

    , 2005
  49. Sharma, M., M.P. Harold, and V. Balakotaiah,

    “Analysis of Storage and Reaction Phases for LNT for Diesel Engine Exhaust Treatment,” Society of Automotive Engineers Journal, OFFL-218

    , 2005
  50. Sharma, M., M.P. Harold, and V. Balakotaiah,

    “Analysis of Periodic Storage and Reduction in Catalytic Monoliths,” Ind. Engng. Chem. Res.44, 6264-6277

    , 2005