Effectiveness Factor Formula:
From: | To: |
Definition: The effectiveness factor is a measure of how much the reaction rate is reduced due to diffusion limitations within porous catalyst particles.
Purpose: It helps chemical engineers evaluate the efficiency of catalytic reactions in porous materials.
The calculator uses the formula:
Where:
Explanation: For a first-order reaction in a spherical catalyst particle, the effectiveness factor can be calculated from the Thiele modulus.
Details: The effectiveness factor indicates what fraction of the catalyst is being effectively used. A value of 1 means no diffusion limitations, while lower values indicate significant diffusion effects.
Tips: Enter the Thiele modulus (must be > 0). The calculator will compute the effectiveness factor using the standard formula for first-order reactions.
Q1: What is the range of the effectiveness factor?
A: The effectiveness factor ranges from 0 to 1, where 1 means no diffusion limitations and lower values indicate more severe diffusion limitations.
Q2: What does the Thiele modulus represent?
A: The Thiele modulus compares the reaction rate to the diffusion rate within the catalyst particle.
Q3: When is the effectiveness factor approximately 1?
A: When the Thiele modulus is small (typically < 0.3), indicating that diffusion is fast compared to reaction.
Q4: What happens at high Thiele modulus values?
A: The effectiveness factor decreases, approaching 1/MT for large MT values.
Q5: Does this formula work for all catalyst shapes?
A: This exact formula is for spherical particles. Other shapes require different formulas.