Modelling of chemical reactors — X Multiple solutions of enthalpy and mass balances for a catalytic reaction within a porous catalyst particle

✍ Scribed by V. Hlaváček; M. Marek; M. Kubíček

• Publisher: Elsevier Science
• Year: 1968
• Tongue: English
• Weight: 1008 KB
• Volume: 23
• Category: Article
• ISSN: 0009-2509
• DOI: 10.1016/0009-2509(68)87093-9

✦ Synopsis

As was already shown, equations describing mass and enthalpy balances for an exothermic reaction taking place inside a porous catalyst particle can have more than one stationary solution. In this paper, two conditions for the existence of multiple solutions were stated: (1) the value of parameter v/3 has to be greater than a certain critical value, (yB)*, (2) Thiele's modulus has to be simultaneously in the definite range Q, G #J G & on the basis of the model, where the state of the particle is described by means of mean values of concentration and temperature. Values of (y/3)* and the critical limits of Thiele's modulus 4, and & for reactions of power and of adsorption type of kinetics were then calculated. Values thus obtained, are in good agreement with correct values, obtained from numerical integration of conservation equations. In the last part of the paper a general procedure was described, which enables one to determine, whether for a given set of values of physical parameters more than one stationary profile of concentration in the catalyst particle can exist. SIMULTANEOUS 1 dr r+GG= 1.