Elements of
Chemical Reaction Engineering
6th Edition



Home



Essentials of
Chemical Reaction Engineering
Second Edition

  Select  Chapter  >>     TOC     Preface     1     2     3     4     5     6     7     8     9     10     11     12     13     14     15     16     17     18     Appendices  
›

By Chapter Hide

  • Objectives
  • Living Example Problems
  • Extra Help
  • - Summary Notes
  • - LearnChemE Screencasts
  • - FAQs
  • - Interactive Computer Modules
  • Additional Material
  • Self Test
  • i>Clicker Questions
  • Professional Reference Shelf

By Concept Hide

  • Interactive Modules
  • -Web Modules
  • -Interactive Computer Games
  • Living Example Problems

U of M Hide

  • Asynchronous Learning
  • ChE 344
  • ChE 528

Chapter 15: Diffusion and Reaction in Porous Catalysts

Additional Homework Problems

CDP15-KB

  The oxidation of ethanol is to be carried out in a trickle bed reactor. The reaction is first-order with respect to oxygen and zero-order with respect to ethanol. The reactor is 30 cm in diameter and 6 m long and the bed porosity is 40%. The Pd/Al 2 O catalyst pellets are 0.5 cm in diameter and have a density of 1800 kg/m 3 . The diffusivity of oxygen in ethanol is 4 x 10 -10 m2 /s and the equilibrium solubility is 4 x 10 -2 kmol/m3 at reaction conditions. The superficial gas velocity is 10 cm/s and the corresponding pressure gradient is 30 kPa/m. The superficial liquid-phase velocity is 0.25 cm/s. The specific reaction rate is 0.03 s -1 . Tortuosity = 3.9,xi]p = 0.6,sigma= 0.8.
     
    (a) Calculate the percent of the total resistance for each transport step.
(b) Determine the conversion of ethanol.
(c) Assuming an axial dispersion coefficient of 0.02 cm 2/s, determine if the plug-flow model was a good assumption.

[2nd Ed. P12-9]