Single-pellet cell for the measurement of intraparticle diffusion and convection
✍ Scribed by Z. P. Lu; J. M. Loureiro; A. E. Rodrigues
- Publisher
- American Institute of Chemical Engineers
- Year
- 1992
- Tongue
- English
- Weight
- 644 KB
- Volume
- 38
- Category
- Article
- ISSN
- 0001-1541
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✦ Synopsis
Abstract
Dynamic analysis of single‐pellet cell for the measurement of diffusion and convection in porous catalysts is revisited. A complete mathematical model for the “diffusion‐convection” cell is solved, and the relation between zero‐and first‐order moments of the cell response and operating parameters is derived. The validity region of the “simplified” boundary condition at the bottom of the pellet is quantified. The effect of the operating parameters on the cell time response to a tracer impulse is analyzed to check the practical range of operation of the system. It also is compared with the chromatographic technique.
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