Wrong-way behavior in packed-bed reactors with "large-pore" catalysts

• Type: Article in International Scientific Journal
• Date: 1994

Authors

Almeida Costa, CA (Author) Other; Quinta Ferreira, RMQ (Author) Other; Alírio Rodrigues (Author) FEUP

Journal

Title: Chemical Engineering Science

Vol. 49 No. 24 A

Pages: 5571-5583

ISSN: 0009-2509

Publisher: Elsevier

Indexing

ISI Web of Knowledge - 3 Citations

Scopus - 4 Citations

Other information

Authenticus ID: P-001-KMB

DOI: 10.1016/0009-2509(94)00352-1

Abstract (EN): The effect of intraparticle convection on the wrong-way behavior of a non-isothermal packed-bed reactor is analyzed. Transient one-dimensional heterogeneous models were used to calculate the dynamic responses of the system: the HTdc model, which takes into account both internal convective and diffusive fluxes and the HTd model, that includes only diffusional resistances inside the particle. The o-xylene oxidation to phthalic anhydride, described by a single first-order irreversible exothermic reaction was used as an example. For a sudden decrease in the feed temperature (T-o), the HTdc model predicts an inverse temperature response along it wide range of inlet concentrations, which becomes more significant for rising C-o values. Wrong-way behavior is also reported by the HTd model, for more severe operating conditions (high values of C-o and T-o), where the temperature excursion can exhibit a sharp transient increase. It is also shown that, for the same operating conditions, the dynamic behavior of the packed-bed reactor depends on the intraparticle Peclet number, lambda(m), that accounts for the competition between convection and diffusion inside the catalyst particle.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 13