Fixed‐Bed Reactors

DOI: 10.1002/14356007.b04_199 In book: Ullmann's Encyclopedia of Industrial Chemistry


The present paper presents the phenomena occurring in fixed bed reactors spanning, from the small scale of single pellet, where reaction and diffusion are competing, to the macroscale of whole apparatus, where dispersion and heat transfer play an important role; the most important models used in describing the behaviour of fixed bed reactors and the dependence of most relevant parameters from the geometrical characteristics of the reactor and from the physical properties of the reacting gases are examined. Advice is given in order to design the reactor choosing the governing parameters in order to have stable and effective performance, avoiding situations with multiple solutions and hence potential instability problems.

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    • "Another important parameter for the reactor design is the ratio between reactor and catalyst particle diameters which affects the heat transfer from the catalyst to the reactor wall. The value of 12, selected in this study, is close to the lower limit of the reference range for industrial operations with a single tube [7]. This choice limits temperature hot spots for exothermic reactions. "
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    ABSTRACT: Cited By (since 1996): 4, Export Date: 13 April 2010, Source: Scopus, CODEN: IJHMA, doi: 10.1016/S0017-9310(01)00008-4, Language of Original Document: English, Correspondence Address: Goldstein, R.J.; Department of Mechanical Engineering, Institute of Technology, University of Minnesota-Twin Cities, 111 Church Street S.E., Minneapolis, MN 55455-0111, United States; email:, References: Das, A.K., Sadhal, S.S., Thermal constriction resistance between two solids for random distribution of contacts (1999) Heat and Mass Transfer, 35 (2), p. 101;
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