Interactive Self-Study Module: Langmuir-Hinshelwood Kinetics

Overview:

This module uses screencasts and an interactive simulation to explain Langmuir-Hinshelwood kinetics. It then provides example problems to allow the user to test themselves. Your retention of material in this module will increase if you write down reasons for your answers to ConcepTests, questions in screencasts, and questions to answer before using interactive simulation, and you try to solve the example problems before watching the screencast solutions. We suggest using the learning resources in the following order:

  1. Attempt to answer the multiple-choice ConcepTest and solve the example problem before watching the screencasts or working with the simulation.
  2. Watch the screencasts that describe Langmuir-Hinshelwood kinetics and answer the questions within the screencasts.
  3. Review important equations for Langmiur-Hinshelwood kinetics.
  4. Use the interactive simulation to further understand the behavior of reactions that obey Langmuir-Hinshelwood kinetics.
  5. Try to solve the example problems before watching the solutions in the screencasts.
  6. Answer the ConcepTests.
  7. Look at the list of key points, but only after you try to list the key points yourself.
Motivation:
  • Catalytic reactions are often modeled using Langmuir-Hinshelwood kinetics. 
  • This module is intended for a reaction engineering/kinetics course. 
Before studying this module, you should be able to:
  • Write down Langmuir isotherms for dissociative and non-dissociative adsorption.
  • Use the Langmuir adsorption isotherm to determine equilibrium loading (Adsorption).
  • Determine rate laws for elementary reactions.
  • Apply the concept of rate-determining (or rate-limiting) step to a reaction mechanism.
  • Apply the steady-state approximation to a reaction mechanism.
  • Apply material balances to Isothermal Plug Flow Reactors (PFRs).
After studying this module, you should be able to:
  • Derive the rate law for a Langmuir-Hinshelwood mechanism where adsorption, surface reaction, or desorption is the rate-limiting step.
  • Predict how reaction rates change with reactant concentrations for Langmuir-Hinshelwood kinetics.
  • Determine the apparent activation energy for a catalytic reaction when certain assumptions are made.