Filtration and catalytic reaction in trickle beds: The use of solid foam guard beds to mitigate fines plugging

Research output: Contribution to journalResearch articleContributedpeer-review

Contributors

  • A. R. Khan Wardag - , Université Laval (Author)
  • M. Hamidipour - , Université Laval (Author)
  • M. Schubert - , Helmholtz-Zentrum Dresden-Rossendorf (Author)
  • D. Edouard - , University of Strasbourg (Author)
  • F. Larachi - , Université Laval (Author)

Abstract

The sensitivity of catalytic reactions to concurrent filtration and fines deposition in trickle-bed reactors (TBRs) was assessed by means of the catalytic hydrogenation of α-methylstyrene from kaolin-kerosene suspension flows. A negative correlation between catalytic conversion and the specific deposit of the bed resulted from the extra mass-transfer step that built up on the collectors in the course of filtration. The severity of the evolving extra mass-transfer step was sensitive to deposit compaction resulting from higher gas superficial velocities. Furthermore, irreversible catalyst activity losses were observed after catalyst cleanup and were ascribed to irretrievable active sites by catalyst intraparticle fines trapping. Fines accumulation in the catalyst bed was notably reduced by means of high-porosity solid-foam modules used as guard filters and placed upstream of, and adjacent to, the trickle bed. Hydrodynamic studies were carried out with alumina and silicon carbide solid foams to assess their role on the distribution of suspension and the reduction of specific deposit and pressure drop in trickle beds. It was found that the foam capture efficiency critically depended on the open connectivity of foam cells and the physicochemical nature of foam materials. The numbering up of foam modules led to reduced overall specific deposits of the beds and pressure drops, foreseeing a prospect for prolonging the hydrotreatment TBR lifetime, using solid foam as guard beds.

Details

Original languageEnglish
Pages (from-to)1729-1740
Number of pages12
JournalIndustrial and Engineering Chemistry Research
Volume51
Issue number4
Publication statusPublished - 1 Feb 2012
Peer-reviewedYes
Externally publishedYes