Chemical Reaction Engineering II
Objectives
This course consists of two parts: ANALYSIS OF NON-IDEAL REACTORS and HETEROGENEOUS CATALYTIC REACTORS. With the first part is intended to provide students with the tools needed to evaluate the deviation from ideality, either through the diagnosis of the causes either through mathematical models predicting the behavior of the real reactor. In the second part it is intended that on the end of the course students are able to determine the amount of catalyst and the reactor volume necessary for a given conversion. In particular it will be dealt with fixed-bed, moving bed and monolithic reactors operating under kinetic or diffusion control, either externally or internally. Special attention is given to the deduction of rate law from the mechanisms of Langmuir-Hinshelwood and Eley-Rideal, the calculation of the mass transfer coefficient, for the case of external diffusion regime, and the determination of Thiele modulus and effectiveness factor, in the case of internal diffusion regime.
General characterization
Code
12598
Credits
6.0
Responsible teacher
Teresa Maria Alves Casimiro Ribeiro
Hours
Weekly - 4
Total - 81
Teaching language
Português
Prerequisites
None
Bibliography
H. Scott Fogler, Elements of Chemical Reaction Engineering, 4rd edition, Prentice-Hall, 2006.
J.L. Figueiredo e F. Ramôa Ribeiro, Catálise Heterogénea, Fund. Calouste Gulbenkian, 1989.
Francisco Lemos, José Madeira Lopes, Fernando Ramôa Ribeiro, "Reactores Químicos", IST Press, Lisboa 2002.
J.F. Le Page, J. Cosyns, P. Courty, E. Freund, J.P. Franck, Y. Jacquin, B. Juguin, C. Marcilly, G. Martino, J. Miquel, R. Montarnal, A.
Sugier, H. van Landeghem, "Catalyse de Contact", Technip, Paris, 1978.
Teaching method
The teaching methods include lectures with PP presentations; laboratory sessions and results modeling using Excel; problem solving sessions; availability of contents in the Moodle page.
Evaluation method
The course evaluation is composed by a written part and a practical
part. The written part consists in two tests or in a final exam. The grade in each test must be equal or higher than 9,45/20 v. The final grade is the weighted average of the written (70%) and the practical (30%) parts. Approval is obtained with the final grade
equal or higher than 9,45/20 v and the grade of the written part not less than 9,454/20. Frequency is mandatory and is obtained with the practical part. The grade will remain valid for a period of two years. The grades can be improved through the repetition of the written or practical parts. In any case the final grade is calculated as described above.
Subject matter
THEORECTICAL
The residence times distribution (DTR). Modeling real reactors by association of ideal reactors. Adsorption isotherms. Mechanisms of Langmuir - Hinshellwood and Eley -Rideal. The fixed bed reactor under kinetic control. Deactivation of catalysts.
The moving bed reactor. External diffusion and chemical reaction. The mass transfer coefficient. Reactors under external diffusion control. Catalyst regeneration: the "Shrinking Core " model. Chemical reaction and internal diffusion. Mole balance to a catalyst pellet. The Thiele modulus and the effectiveness factor.
PRACTICAL
Determination of the DTR in a bench scale CSTR. Comparison of conversion with values calculated from the proposed models, for a known reaction. Reaction of ethyl acetate with methanol catalyzed by an acid resin. Effect of the pellets size on the apparent reaction rate.
THEORECTICAL-PRACTICAL
Problem solving classes.