[WELCOME]

SE Reactors Inc.

c/o David Hill
701 Christie Lake North Shore
RR 4, Perth ON K7H 1B6
P: 613 267 4942

President:
Bohdan W. Wojciechowski, BASc, MASc, PhD,
Professor Emeritus, Chemical Engineering,
Queen's University, Kingston, ON
K7L 3N6

Res: 413 Interamerica Blvd. #1
328C-35
Laredo TX 78045-8285 USA
P: 941 803 0644

email: bohdanw@aol.com

The technology:

SE Reactors Inc. is a Canadian company, incorporated in 1993 to commercialize the Temperature Scanning technology developed by Professors Bohdan Wojciechowski (Department of Chemical Engineering) and Norman Rice (Department of Mathematics and Statistics) at Queen’s University at Kingston, ON.

Under license from PARTEQ Innovations, the technology transfer arm of Queen's University, SE Reactors Inc. offers the Temperature Scanning Reactor (TSR), a micro-reactor for research in kinetics and catalysis, and the Temperature Scanning (TS) software for reactor control and data handling and interpretation.

Catalyst Development:
The multi-billion dollar chemical synthesis and process industries are dependent on the use of catalysts, and constantly searching for improvements that will reduce costs, increase productivity, and reduce unwanted by-products. They have invested heavily in catalyst research in order to optimize reactor design, and to attempt to understand the links between catalyst activity or selectivity and the kinetic parameter changes engendered by changes in catalyst formulation.

Although major progress has been made in developing new catalysts and processes, this progress has remained largely empirical and heuristic. In terms of developing models and mechanisms, the results have been largely unconvincing and often contradictory.

A consequence of the disappointing returns from R&D investment in catalysis has been the closure or down-sizing of many catalyst research facilities in the chemical and petrochemical industries, in spite of the fact that many process design engineers feel that the reaction rate models available in the literature are inadequate as a basis for detailed catalytic process design. There is increasing dependence on out-sourcing of catalyst and process development to dedicated R&D organizations which, in order to be cost competitive, must concentrate on quick studies within narrow regions of performance space. Very little general or fundamental understanding comes from such work.

What if, instead of waiting for weeks to obtain a single-point evaluation of a new catalyst as is currently the case, one could evaluate each new formulation over a range of industrially important conditions in a day or less?

Such a capability would give a much broader view of the performance of each catalyst sample than the single point of an isothermal experiment. In subsequent days one could observe how the constants in the best mechanistic rate equation change with incremental changes in catalyst formulation. In other words, incremental changes in the catalyst can be directly associated with changes in activity and selectivity, the two principle measures of catalyst performance.

This would turn catalysis into a true predictive science, and facilitate rapid advances, not just in the fundamental understanding of the kinetics and mechanisms of catalytic reactions, but also in industrial applications such as catalyst formulations, treatments, and process conditions.

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A new kinetics research instrument:

SE Reactors' Temperature Scanning Reactor (TSR) is a new kinetics research instrument that can collect and interpret masses of data in kinetic studies of catalytic as well as non-catalytic reactions. With a TSR, thermal steady-state does not need to be established in order to generate useful results.

This is not simply an automated version of traditional hardware for reaction studies, but an instrument which uses a totally new procedure to extract kinetic data rapidly and accurately, and is as significant and versatile for kinetic studies as was the gas chromatograph when it was introduced in the field of analytical instrumentation.

For example, we have examined the oxidation of CO on a Pt/Al2O3 catalyst. In one five-hour experiment, an experimental evaluation of the kinetics of this reaction was conducted on one catalyst, at one pressure and feed composition, over a temperature range from ~200EC to ~300 EC. The satisfactory kinetic rate expression governing the reaction was identified, using about 3500 conversion-temperature-rate triplets (X, T, r) from the unlimited mass of raw data collected from this one experiment.

Reaction Phenomena via 3-D Mapping
A temperature scanning experiment in a fully automated TSR gathers data for 3-D mapping of the surfaces which offer a view of reaction phenomena. Like a mapping satellite, which surveys the terrain it overflies in terms of latitude-longitude-elevation, a TSR collects data on the temperature-space time-conversion (T,t,X) surface along well defined traverses. To interpret this raw data, which as it stands is merely qualitative, the TS algorithms convert it into conventional data, consisting of conversion-temperature-
rate (X,T,r) triplets, suitable for reactor design or for rate expression fitting.

To understand how one TS experiment is able to generate the large amounts of data needed to determine the applicable rate expression, consider that reaction rates correspond to slopes (that is, dX / dt) on the experimental (T,t,X) surface.

Once this surface is well defined, there is an unlimited number of (X,T,r) triplets available from a single experiment. The TSR is programmed to determine the shape of the (X,T,r) surface at the desired level of precision by taking as many traverses over the kinetic surface as one may wish. Each traverse, or run, takes half an hour or so, and 10 runs are usually enough to map the surface.

An eight-hour day is therefore more than enough to map the entire kinetic surface in satisfactory detail, as shown above. By contrast, a traditional isothermal run at "standard conditions" provides only one point on this surface.

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TSR Applications:

The Temperature Scanning Reactor can yield in one day enough kinetic data to discriminate between many alternative mechanistic rate expressions for a given catalyst sample. A short preliminary program of fundamental studies can therefore readily identify a broadly applicable, perhaps mechanistic, rate expression for the routine evaluation of a series of catalyst formulations in a development.

Recent Advances:
Techniques have been developed for filtering noise from the large amounts of data recovered from TS experiments and for dealing with catalyst decay. Applicable methods of analysis include gas chromatograph as well as mass spectrometer and simpler systems such as electrodes. Software for the application of the TS methodology to adsorption studies using Stream Swept Reactors has also been developed.

TSR Users:
Temperature Scanning Reactors are currently in use in three major research laboratories, two in the United States and one in Germany. A satisfied TSR user has told us he can perform complete system studies in as little as two weeks using the TSR -- studies that took his laboratory up to one year using conventional isothermal methods. After extensive use of the TSR, he is still discovering new aspects of its capabilities. Two publications by users are summarized in the publications list.

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Purchase options:

Turn-key System:
The TSR can be purchased from SE Reactors Inc. as a turn-key system. The standard TS-PFR (plug flow) with quadrupole MS sells for approximately US$220,000.* Prices for other designs will vary widely, according to operating and analytical requirements. Other possible configurations include batch, continuously-stirred and stream-swept reactors. Analytical methods can include mass spectrometer, gas chromatograph, and others.

License option:
Or, SE Reactors Inc. can license the technology to your company, for in-house use, at a cost of $US70,000* for one reactor, and provide the control, data-logging and interpretative TS software. SER will also provide, at cost, assistance in the design, construction and commissioning of your own hardware to ensure that it can follow correct TS procedures.

*Prices are based on standard configurations and subject to change without notice

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TSR Research History

Professor Bohdan Wojciechowski taught Chemical Engineering at Queen's University, Kingston, ON, from 1965 to 1997, and was appointed full professor in 1972. His research interests focus on kinetics and catalysis, and he has made a succession of contributions in these fields, starting with his PhD work which resolved long-standing questions regarding the action of inhibitors in pyrolysis reactions, and moving on to research related to hydrocarbon conversion and catalysis. His hydrocarbon studies have ranged from pure hydrocarbon reactions to multi-component reactions in the presence of catalyst decay. In 1992 he received the Chemical Institute of Canada's Award in Catalysis in recognition of his overall contributions to the field of catalysis research.

Following his PhD studies, during three years in the petroleum industry (1962-65) his interests shifted from homogeneous hydrocarbon conversion to catalytic studies. Shortly after joining Queen's University in 1965, Professor Wojciechowski proposed his Time on Stream theory of catalyst decay. This concept, which began the establishment of a mathematical foundation for the field of catalytic cracking, was extended by the addition of Optimum Performance Envelopes which he introduced a few years later.

With the combined power of these two concepts, as well as other contributions such as the "refractoriness effect", all applied in a program of systematic, mathematically-rigorous, consistent and thorough studies, he and his colleagues have made a series of significant advances in the understanding of catalytic systems, including the recent Chain Mechanism concept of catalytic cracking. The cumulative nature of his work is demonstrated by the fact that many of the concepts developed in his PhD research on gas-phase inhibition continue to be fundamental to his contributions to understanding the complexities of catalytic cracking.

Among his other areas of research, Professor Wojciechowski has contributed a versatile isotherm to the field of adsorption on heterogenous surfaces, and was involved in a definitive study of the kinetics of Fischer-Tropsch and other synthesis reactions. The findings from this latter work were collected and published in two review articles.

Professor Wojciechowski's research has concentrated on building a soundly-based, systematic and consistent body of knowledge on the formation and rearrangements of hydrocarbon molecules. It has therefore been of interest not only to academic colleagues but also to researchers in applied fields such as catalyst manufacturing, transportation fuels, petrochemicals, and other catalytic applications including environmental protection.

Drawing on this body of knowledge, and in particular on recent advances made by his group in understanding the mathematics of catalytic reactions, he and Professor Norman Rice have developed the Temperature Scanning Reactor (TSR), which abandons the conventional isothermal paradigm for studying catalytic and non-catalytic reaction processes. This new technology promises to increase research productivity for both academic and industrial applications and place kinetics and catalyst studies on a firm quantitative and mathematical foundation. It is available to researchers through this company, SE Reactors Inc., established by Professor Wojciechowski for this purpose.

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About Dr. Bohdan Wojciechowski:

Professional Experience:
1961-62 Postdoctoral Fellow, NRC Canada
1962-65: Senior Research Chemist, Mobil Oil
1965-1996: Assistant, Associate & Full Professor, Queen's University
Various University Chairmanships, etc.
Lectured or consulted in more than 100 universities and laboratories in over 40 countries.
1993+: President, SE Reactors Inc.
1996+: Professor Emeritus, Queen’s University

Research Interests:
Kinetics and Catalysis, Catalytic Cracking, Fischer Tropsch Synthesis, Catalyst Decay, Adsorption, Gas Phase Kinetics, Reactor Design, Temperature Scanning Technology

Publications:
Over 170 refereed publications
3 books (Catalytic Cracking; Kinetics for Chemical Engineers, Experimental Methods in Kinetic Studies)
5 patents; plus reports, presentations and articles.

Publications and Patents

Industrial Reports By Users of the Temperature Scanning Technology
1. Leibner, C., Wolf, D., Baerns, M., Kolkowski, M., and Keil, F.J.; "A high-speed method for obtaining kinetic data for eothermic or endothermic catalytic reactions under non-isothermal conditions illustrated for ammonia synthesis", Applied Catalysis, A,: General p. 240(1-2), 95-110 (2003).

Abstract:
A detailed analysis of the method for fast acquisition of kinetic data by means of a polythermal temperature- ramping reactor (PTR) as suggested by Wojciechowski in 1995 was performed. The ammonia synthesis over a commercial. Fe catalyst (BASF) was taken as an example. Kinetic evaluatioon was based on a kinetic model as reported by Sehested et al. in 1999. As a result of data analysis, the experimental molar rate of change of ammonia could be described adequately over a wide range of N2 and H2 partial pressures as well as temperature. The pre-exponential factors, activation energies and adsorption enthalpies are in reasonable agreement with data for promoted iron catalysts in the literature. Accordingly, the PTR method was evaluated as an efficient tool for kinetic data analysis. The number of experiments including differential initial conditions can be significantly diminished since PTR experiments have not to follow the strict sequence of of varying one experimental parameter after the other by keeping all others constant. The collected exit concentrations, exit temperature and contact time are correlated by spline-functions which allow the extraction of functional relationships required for derivation of rate expressions. If the steady state of the catalyst is rapidly attained, temperature ramping allows fast continuous data acquisition. Thus the PTR method has the potential of significantly reducing the time needed for determining reliable kinetics over a wide range of operating conditions.

2. Domke, S.B., Pogue, R.F., Van Neer, F.J.R.,Smith, C.M. and Wojciechowski, B.W., "An Investigation of the Kinetics of Ethylbenzene Pyrolysis Using a Temperature-Scanning Reactor", Ind. Eng. Chem. Res., 40, 5878-5884 (2001)

Abstract:
A new technique of examining kinetic data has been examined. This involved gathering raw data at the end of a plug-flow reactor undergoing temperature ramping. The data acquired in this way was made to yield many isothermal sets of rate data suitable for fitting to candidate rate expressions. This technique was applied to the thermal decomposition of ethylbenzene. The resulting fit to a rate expression proposed previously in the literature was good. The parameters obtained compare well to literature values, and our fitted rate expressions yield calculated conversions in agreement with those reported in the literature. We believe that temperature scanning methods used in experimental reactors yield correct rate data and are considerable faster for rate data acquisition than conventional isothermal reactors.

Publications by the Principal Investigators

Books:
Wojciechowski, B.W. and Rice, N.M, Experimental Methods in Kinetic Studies, Elsevier Science BV, Amsterdam, 310 pages. ISBN 0444 51314 0 (2003)

Summary:
This book is a guide to kinetic studies of reaction mechanisms. It reviews conventional reactor types and data collection methods, and introduces a new methodology for data collection using Temperature Scanning Reactors.

Temperature scanning theory and application are described in detail for a variety of reactor types. The theoretical and experimental methods described allow researchers to relate catalyst formulation and performance to fundamentally meaningful kinetic parameters of the rate expression. Effects of changes in catalyst formulation can then be understood in terms of the rate processes involved and the related changes in kinetic rate parameters. Catalyst design becomes simpler, faster, more economical, more target-specific, and more rational. TS methods take advantage of the power of computers for collecting and interpreting large quanties of data under non-steady-state conditions. The method will rapidly yield two dimensional sets of data that are transformed into three dimensional "reaction surfaces" containing enough information to allow for the use of sophisticated mathematical procedures and for reliable interpolation without using curve fitting. For the first time, researchers can have access to unlimited amounts of unprejudiced data for rate-model evaluation. TSR data fitting and interpretation are covered, including methods of error removal and evaluation of multiparameter fits. Several sets of actual TSR experimental results are presented, followed by practical applications of the use of mechanistic rate expressions.

The book provides a theoretical and practical foundation for a new approach to kinetic data gathering, a new patented technology that will support a revival of kinetic studies as a useful approach to the fundamental understanding of chemical reaction mechanisms and of the consequent reaction kinetics. This in turn will to put catalyst development on a quantitative and rational foundation

Articles:

Wojciechowski, B.W. "The Temperature Scanning Adiabatic Plug-Flow Reactor", Can.J. Chem. Eng. 70, 721 (1992)

Wojciechowski, B.W. and Rice, N.M., "Temperature Scanning Plug Flow Reactor", Chem. Eng. Sci., 48(16), 2881-2887 (1993)

Wojciechowski, B.W. and Wojciechowski, M.J., "Kinetic Measurements Made Easy", ChemTech, May 1996.

Wojciechowski, B.W., "The temperature scanning reactor. I: Reactor types and modes of operation", Catalysis Today, 36 (1997) 167-190.

Rice, N.M. and Wojciechowski, B.W., "The temperature scanning reactor. II: Theory of operation", Catalysis Today, 36 (1997), 191-207."

Asprey, S.P, Rice, N.M. and Wojciechowski, B.W., "The temperature scanning reactor. III: Experimental procedures and data processing", Catalysis Today, 36 (1997), 209-226.

Wojciechowski, B.W., "Temperature Scanning Reactors: How to enjoy kinetic studies", La Chimica e l'Industria, May 1997.

Asprey, S.P, Wojciechowski, BW. and Peppley, B.A., "Kinetic Studies Using Temperature Scanning: the Steam Reforming of Methanol", Applied Catalysis A. General 179 (1999) 51-70.

Wojciechowski, B.W., "The Application of Temperature Scanning to Adsorption Studies", Annales, UMCS, Sec AA Chemia, LIV/LV (1999/2000) 23-41.

Wojciechowski, B.W. and Asprey, S.P., "Kinetic studies using temperature scanning: the oxidation of carbon monoxide", Applied Catal, A:General, 190 (2000) 1-24.

Patents:
S Wojciechowski, B.W. and Rice, N.M., "Temperature Scanning Reaction Method", US Pat. 5,340,745, 8/23/94.

S Wojciechowski, B.W. and Rice, N.M., "Temperature Scanning Reactor Method", US Pat 5,521,095, 5/28/96.

S Wojciechowski, B.W. and Rice, N.M., "Temperature Scanning Reactor Method", US Pat. 5,593,892, 1/14/97.