The TSR A Kinetics Instrument

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The TSR A Kinetics Instrument

• B.W.Wojciechowski
• President
• SE Reactors Inc.

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What Is a TSR

• A TSR is a kinetics instrument built around any
  of the established reactor configurations - PFR,
  CSTR or BR - but operated in an unconventional
  way
• the temperature of the input stream and of the
  reactor is ramped in a prescribed way, rather
  than being maintained at isothermal conditions.

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The Advantage of a TSR

• By ramping the temperature, one quickly obtains
  data over a range of temperatures rather than at
  one isothermal condition.
• TSR operation requires a number of such rampings,
  at different feed rates, and therefore always
  yields data over a range of reaction temperatures
  and conversions.

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Interpreting TSR Data

• The raw data from the TSR is uninterpretable by
  conventional means. It is made interpretable by
  the use of algorithms patented by SE Reactors.
• The algorithms are based on fundamental equations
  for the mass and heat balances present during
  temperature scanning, and do not involve any ad
  hoc assumptions.

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How Efficient Is Temperature Scanning?

• A TSR experiment can be completed in as little as
  5 hours. The raw data is then processed to yield
  an unlimited number of rates within the range of
  temperatures and conversions observed.
• The masses of data generated allow us to see rate
  expressions as 3D surfaces in (X, T, t) or (X, T,
  r) or another space.

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Kinetic Runs Seen As Surveying

• TSR results make it clear that kinetic studies
  involve a survey of such a kinetic surface. Its
  shape is surveyed by measuring the
• (X, T, t) co-ordinates at several points.
• An algebraic expression is fitted to the rate
  surface derived from these points.
• Because of the laborious nature of the
  experimental work involved in this surveying
  method, conventional kinetic studies collect a
  sparse and error-prone set of survey points.

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Kinetic Surface Defined by a TSR
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Kinetic Survey by TSR

• TSR surveying methods are quite different.
• TSR methods can be compared to surveying of a
  surface by satellite. Continuous traverses of the
  surface are taken along several correlated paths.
• Both the paths and the traverses are governed by
  internal consistencies. This allows us to apply
  powerful mathematical procedures designed to
  eliminate noise.

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A Systematic Survey by TSR
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What is the Final Result?

• The TSR supplies enough well-conditioned data so
  that complex mechanistic rate expressions can be
  fitted to the data with confidence.
• A TSR can perform as many as three experiments
  per day, each yielding a complete surface in the
  range of variables investigated, offering a
  thorough understanding of the kinetics involved.

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Mechanism of MeOH Reforming
The Steam Reforming of Methanol presents a
complicated reaction system studied using the
TSR. Two types of sites, many surface
intermediates, and highly coupled reaction rates
are connected by equilibria and common
intermediates. This results in three coupled,
complex rate expressions, making parameter
estimation difficult. The overall reaction
chemistry can be envisaged as a combination of
three equilibria
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Equilibria in MeOH Reforming
Steam Reforming
Decomposition
Water Shift
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The Kinetics of the Reaction
The Steam Reforming Rate
Decomposition Rate
The Water Shift Rate
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Confirming the Validity of the Parameters
CO2
CO
CH3OH
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Temperature Scanning vs Isothermal Operation

• The TSR yields all the necessary kinetic data in
  a matter of hours, not months
• TSR data is reliably purged of random
  experimental error by the use of advanced
  mathematical methods
• The quantity and quality of data available from
  the TSR makes the fitting of complex or
  mechanistic rate expressions believable
• The TSR allows a deeper understanding of the
  reaction kinetics, with or without the fitting of
  a mechanistic rate expression.
• The hardware, analysis and system calibration
  procedures are similar to those commonly used

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The Temperature-Scanning Plug-Flow Reactor A
Kinetics Instrument