Application of the chromatographic method to determine the effective diffusivity in spherical γ-alumina pellets using convolution theorem and a fictitious column

Runtong Zhang, Stan T. Kolaczkowski

Research output: Contribution to journalArticle


It is shown how the chromatographic experimental technique may be applied, in combination with the use of convolution theorem, to determine the effective diffusivity of a binary pair of non-reacting gases, in spherical γ-alumina pellets (1.0 mm diameter). The experiments were performed on a packed bed (i.d. = 13.8 mm), with two different packed bed depths of 200 and 400 mm, which enabled the first and second moments for a fictitious bed length of 200 mm to be determined. The effective diffusivity of He in N2 was 9.56 × 10−7 m2 s−1 for the γ-alumina pellets, and for N2 in He was 2.31 × 10−7 m2 s−1. Using the parallel pore model, the apparent tortuosity factor was back-calculated and the value was found to be 2.2 –3.5 for the pellets studied.

Original languageEnglish
Pages (from-to)248-258
Number of pages11
JournalChemical Engineering Research & Design
Publication statusPublished - 1 Jul 2017



  • Chromatographic method
  • Effective diffusivity
  • γ-alumina beads

ASJC Scopus subject areas

  • Chemistry(all)
  • Chemical Engineering(all)

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