Chemical kinetics - Reaction engineering

Module Notes
Faculty Member (Members):
Postgraduate, Spring Semester
Module Type: Core Courses
Teaching Language: English
Course Code: GCEHM-A501
ECTS Credits: 12
Module Availability on Erasmus Students: No
Student's office hours: Wednesday, 11:00-12:00 (S. Bebelis)
Module Details

1. Chemical kinetics: Basic concepts

  • Rates of chemical reactions. Reaction order and stoichiometry. Extent of reaction and conversion.  Simple and complex reactions. Selectivity and yield. Matrix representation for analysis of reaction networks.

2. Reaction mechanisms

  • Elementary steps.  Rate determining step(s) in consecutive reactions.  The steady state approximation.  Free radical or chain mechanisms.
  • Catalytic kinetics: Adsorption, surface reaction and desorption. Isotherms. Modelling the overall rate of catalytic reactions. Kinetics of catalysts poisoning and deactivation.

3. Theoretical basis of chemical kinetics

  • Potential energy surfaces, Collision theory, Transition state theory. Other theories.
  • Modern methods: Quantum Mechanics, Density Functional Theory

4. Experimental methods in kinetics

  • Interpretation of kinetic data
  • Methods of determining the reaction rate expression. Sensitivity analysis.

5. Liquid phase reactions

  • Diffusion controlled reactions
  • Cage effects and other effects
  • Electron transfer reactions: Inner sphere & outer sphere mechanism
  • Homogeneous catalysis
  • Reactions of charged species in solution

6. Chemical Reactors: Basic concepts

  • Ideal reactors (batch and semi-batch reactors, CSTR, PFR, plug flow with recycle reactors): Isothermal and non-isothermal operation, Gas phase reactions with density change: conversion- concentration relationship, Cascades of reactors, Multiple steady states and stability in CSTRs
  • Multiple reactions in ideal reactors, Selectivity and yield, Reactor choice and operation profile for maximizing selectivity/yield
  • Non-ideal reactors: Residence time distribution. Concepts of mixing (macromixing, micromixing). Laminar flow reactors. Modelling of non-ideal reactors: Zero-parameter models (segregation and maximum mixedness models), One-parameter models, Compartment models. Prediction of conversion in non-ideal reactors.
  • Scale up of chemical reactors

7. Fluid-Solid non-catalytic reactions and reactors

  • Progressive-conversion model
  • Shrinking unreacted-core model: Reaction rate for particles of unchanging shape and for shrinking particles. Determination of the rate-controlling step.
  • Application to design

8. Transport effects in heterogeneous catalytic systems

  • Interfacial gradient effects: External mass and heat transfer resistances. External effectiveness factor. Effect of interfacial gradients on reaction rate and on selectivity
  • Intraparticle gradient effects: Pore diffusion. Diffusion and reaction inside catalysts particles. Internal effectiveness factor. Effect of intraparticle mass and heat transfer resistances on reaction rate and selectivity.
  • Combined interfacial and intraparticle gradient effects: Overall effectiveness factor. Calculation of the global rate. Diagnostic experimental criteria for the relative importance of the interfacial and intraparticle heat and mass transfer resistances.
  • Poisoning of heterogeneous catalytic reactions: Poisoning models (pore-mouth poisoning, uniform poisoning). Effect of interfacial and intraparticle transport resistances on poisoning.

9. Fixed-bed catalytic reactors

Factors involved in the analysis and design of fixed bed reactors (FBR). Axial and radial dispersion and temperature variations. The fundamental mass, energy and momentum balance equations. Modeling of fixed bed reactors:  Pseudohomogeneous models (the one-dimensional plug flow model, the one-dimensional model with axial dispersion, Two-dimensional pseudohomogeneous models), Heterogeneous models (One-dimensional model accounting for interfacial gradients, One-dimensional model accounting for interfacial and intraparticle gradients, Two-dimensional heterogeneous models).

10. Fluidized-bed catalytic reactors

Basics of fluidization. Modeling of fluidized bed reactors: Davidson-Harrison and Kunii-Levenspiel models. Other models.

11. Three-phase catalytic reactors

  • Slurry reactors (collection and interpretation of laboratory data, Design of slurry reactors).
  • Trickle bed catalytic reactors (Mass transfer rate to the catalytic centers, Design of trickle bed reactors)

12. Gas-liquid and liquid-liquid reactors

  • Fluid-fluid reactions
  • Kinetics and transport phenomena in gas-liquid reactors (Two-film theory. Penetration theory. Surface renewal theory). Reactor design for gas-liquid reactors: Bubble column gas-liquid reactors. Other types of gas-liquid reactors (contactors)
  • Classification of liquid-liquid reactors. Experimental data and correlations for liquid-liquid reactors. Design of liquid-liquid reactors

13. Other reactor types: Basic description

Moving-bed reactors. Membrane reactors. Distillation column reactors. Microreactors. Sonochemical reactors. Photochemical reactors. Electrochemical reactors.

Course Textbooks

  1. M. Boudard, Kinetics of Chemical Processes, Butterworth-Heinemann (1991).
  2. G.F. Froment, K.B. Bischoff, J. De Wilde, Chemical Reactor Analysis and Design, 3rd Ed., John Wiley & Sons (2011).
  3. H.S. Fogler, Elements of Chemical Reaction Engineering, 5th Ed., Pearson Education Inc, Upper Saddle River, NJ (2016)
  4. C.G. Hill, T. W. Root, Introduction to Chemical Engineering Kinetics and Reactor Design, 2nd Ed., John Wiley & Sons, Hoboken, NJ (2014)
  5. L.K. Doraiswamy, D. Üner, Chemical Reaction Engineering: Beyond the Fundamentals, CRC Press- Taylor & Francis Group, Boca Raton, FL (2014) 

 

Additional reading

  1. P. Atkins, J. De Paula, Atkins' Physical Chemistry, 10th Ed., Oxford Univ. Press, Oxford, UK (2014)
  2. M. Soustelle, An Introduction to Chemical Kinetics, John Wiley & Sons, Hoboken NJ (2011)
  3. M.E. Davis, R.J. Davis, Fundamentals of Chemical Reaction Engineering, McGraw-Hill Higher Education (2003).
  4. O. Levenspiel, Chemical Reaction Engineering, 3rd Ed., Wiley, New York (1999).
  5. J.  Smith, Chemical Engineering Kinetics, 3rd Ed., McGraw-Hill, New York (1981).
  6. J. B. Rawlings, J.G. Ekerdt, Chemical Reactor Analysis and Design Fundamentals, 2nd Ed, Nob Hill Publishing, LLC, Madison, WI (2012).