reaction kinetics and reactor design

[...]... 1.2 1.3 1.4 1.5 1.6 1.7 1.8 1.9 Mass Conservation and Chemical Reaction Reaction Rate Equations: The Mass Action Law Temperature Dependence of Reaction Rate Rate Laws and Integrated Forms for Elementary Steps Kinetics of ``Nearly Complex'' Reaction Sequences Kinetics of Complex Reaction SequencesÐChain Reactions Chemical Equilibrium Reaction Rates and Conversion in Nonisothermal Systems Interpretation... 7.3 Contents Surface Reactions and Nonideal Surfaces Enzyme and Microbial Kinetics Interpretation of the Kinetics of Reactions on Surfaces Decline of Surface Activity: Catalyst Deactivation Exercises Notation Introduction to Chemical Reactor Theory Reaction in Mixed or Segregated Systems Age Distributions and Macromixing Mixing Models: Reactors with Ideal Flows Applications of Ideal Reactor Models Temperature... are 1 2 To determine zA and zB given a certain type and size of reaction process To determine the type and size of reaction process needed to produce a speci®ed zA and zB Two factors enter into this problem The ®rst is the stoichiometry of the reaction transforming A to B Chemical equations as normally written express the Figure 1.2 Chemical reaction process Apparent Reaction Kinetics 3 relationship... 1 1.4.3 Rates and Conversions for Some Reversible Reactions The most important forms for reversible reactions are ®rst order, forward and reverse, and second order, forward and reverse If change in the number of mols occurs and order follows stiochiometry, the reversible reactions can also have forward and reverse steps of di€erent order Since in the following presentation we treat the reactions as... the rate of reaction For a speci®ed volume element,  of reaction mixture within the process and under steady conditions: …mass A into =time† ˆ …mass A out of =time ‡ mass A reacted in =time† …1-14† Apparent Reaction Kinetics 5 (a) (b) Figure 1.3 (a) Mass balance with chemical reaction on a volume element of reaction mixture (b) Traveling batch reactor as shown in Figure 1.3(a) The reaction term... reaction ˆ …1=V†…dMi =dt† ˆ rate …1-11a† or ri ˆ …change in mols of i†=…time-volume reaction ˆ …1=V†…dNi †…dt† ˆ rate …1-11b† 4 Chapter 1 where i is reactant or product, V the volume of the reaction mixture and M and N are mass and mols, respectively The rate is positive for change in product and negative for change in reactant Most of our applications will deal with the use of molal quantities and, ... in Ideal Reactors Catalyst Deactivation in Flow Reactors Other Fixed Beds and Other Waves: Ion Exchange and Adsorption Exercises Notation Modeling of Real Reactors Deviations from Ideal Flows Modeling of Nonideal Flow or Mixing E€ects on Reactor Performance Combined Models for Macroscopic Flow Phenomena Modeling of Nonideal Reactors Exercises Notation Thermal E€ects in the Modeling of Real Reactors... a gas reaction with di€ering net stoichiometric coecients for reactants and products Further, equation (1-16) as written employs a mass average velocity; if the rate de®nition is in molal units, then the molal average velocity must be used The batch reactor and plug ¯ow reactor are two di€erent types of reactors that are extremely important in both the analysis and implementation of chemical reaction. .. a and b; yes only if a ˆ b Rewrite the reaction as A ‡ …b=a†B ‡ …c=a†C Á Á Á 3 …l=a†L ‡ …m=a†M ‡ Á Á Á Clearly …b=a† mols of B react for each mol of A, and so on The rate of reaction of any constituent i is then related to the rate of reaction of A by ri ˆ r…i =…A † where  are the individual stoichiometric coecients, positive for products and negative for reactants, and r ˆ ÀrA For reversible reactions... equation and the signi®cance of the activation energy in Chapter 2 The exponential dependence of rate on temperature makes problems involving reaction kinetics in nonisothermal systems extremely nonlinear They are among the most interesting and often the most challenging to be found in chemical reaction engineering 1.4 Rate Laws and Integrated Forms for Elementary Steps 1.4.1 Individual and Overall Reactions . John B. Reaction kinetics and reactor design / J.B. Butt. ± 2nd ed., rev. and expanded. p. cm. ± (Chemical industries ; v. 79) Includes index. ISBN 0±8247±7722±0 (alk. paper) 1. Chemical kinetics. . chemical reactor design and analysis models. A parallelism between mixing models and reactor models has been maintained in order to demonstrate clearly how reaction kinetic laws ®t into reactor design. . Reactions on Surfaces 169 3.1 Adsorption and Desorption 170 3.2 Surface Reactions with Rate-Controlling Steps 187 ix 3.3 Surface Reactions and Nonideal Surfaces 194 3.4 Enzyme and Microbial Kinetics