Analysis of a Packed Bed Reactor
BGHiggins/ECH256/Mar_2011
Problem Statement
Consider the dehydrogenation of A to B in an adiabatic packed bed catalytic reactor:
A F B + H2
You are given the following data for the reaction:
Feed temperature: 1000 K
Feed

University of California
Department of Chemical Engineering
& Materials Science
ECH256 Kinetics and Reaction Engineering
MidTerm Exam, Winter 2013
Exam Guidelines
Due Date: Thursday February 14: Hand during class period
Format: Take-home Exam. You are not

University of California
Department of Chemical Engineering
& Materials Science
ECH256 Kinetics and Reaction Engineering
Final Take-Home Exam, Winter 2009
Exam Guidelines
Due Date: Thursday March 19, 5:00 pm:
Format: Take-home Exam. You are not to discuss

ECH 256: Chemical Kinetics and Reaction Engineering
Overview of Undergraduate
Chemical Reaction Engineering and Kinetics
Lecture 3:
Introduction to Homogeneous Kinetics
Brian G. Higgins
Department of Chemical Engineering and
Materials Science
University o

Stagnation Flow in a Finite Gap
BGHiggins/UCDavis/ECH256/Feb_07
Background
In these notes we extend the analysis of axisymmetric stagnation flow originally analyzed by Homann (1936) on
the semi-infinite domain to an equivalent flow that is confined betwee

Stagnation Flow with Chemical
Reaction in a Finite Gap
BGHiggins/UCDavis/ECH256/Feb_07
Background
We consider axisymmetric stagnation flow confined between two parallel disks. The fluid is an ideal gas mixture
consisting of two species. The top disk, loca

Notes on Multicomponent Diffusion
BGHiggins/UCDavis/ECH256/Feb_09
Preliminaries
In these notes we will derive the governing species balance equations for reacting system involving species.
Our focus will be on the diffusional flux terms in the species bal

Species Jump Condition
BGHiggins/UCDavis/ECH256/Feb_07
Introduction
In these notes we will derive the species jump condition at an interface separating the b-phase from the g-phase.
Our starting point is the species balance equations (we will work with th

Soul of a Reaction Diffusion Problem
BGHiggins/UCDavis/May_08
Introduction
In these notes we examine carefully all the steps that lead to the solution of a binary diffusion problem involving
heterogeneous catalysis. We consider a species A that diffuses t

Turning Points And Bifurcation Points
BGHiggins/UCDavis/Feb_09
Background
Suppose we have the following function (Seydel, 1988)
f Hy, lL = I1 - l + Hy - 2L2 M Hy - l + 2.75L
(1)
and we would like to interrogate the solution of
f Hy, lL = 0
(2)
In this exa

Nonlinear Analysis: A Case Study
Introduction
In this notebook we analysis the dynamics of the following system of ODEs
u
= m H6 u + 5 vL - 3 u2 - 4 u v - v2 = f1 Hu, v, mL
t
(1)
v
= - 10 m u - H2 + 9 mL v - 10 u2 - 10 u v - 3 v2 = f2 Hu, v, mL
t
The is

Primer on Linear Systems of ODEs
BGHiggins/UCDavis/Feb_09
Introduction
Linear systems of ODEs arise in the study of the dynamics and stability of nonlinear systems of evolution equations. Consider
the following nonlinear evolution equation in n :
U
t
= F

Classification of Bifurcation Points in 1-D
BGHiggins/UCDavis/Feb_09
Background
Suppose we have a nonlinear ODE given by
U
t
= F HU, mL
(1)
Now at steady state (or at equilibrium if you are a physicist/chemist) we have
F HU, mL = 0
(2)
F HU, mL = m U - U

Primer on Eigenvalues and Eigenvectors
BGHiggins/UCDavis/Feb_09
Introduction
In this notebook we discuss the solution of the following matrix problem
Ax = l x
(1)
where A is a n n matrix, x is a 1 n column vector, and l is a scalar constant. Matrix probl

Stagnation Flow
BGHiggins/UCDavis/ECH256/Feb_07
Background
In this notebook we will study steady flow impingement on a stationary circular disk. The plane of the disk is
taken to be perpendicular to the z- coordinate direction. Far from the plane of the d

Stefan-Maxwell Equations
BGHiggins/UCDavis/ECH256/Mar_09
Background
The Stefan-Maxwell equations are used to describe multicomponent diffusion in an ideal gas mixture. A readable account of the derivation can be found in Taylor and Krishna (1993).
To moti

UNIVERSTY OF CALIFORNIA
Department of Chemical Engineering and Materials Science
ECH256 Chemical Kinetics and Reaction Engineering
HW Assignment #3; Due Thursday Feb 6
B. G. Higgins Winter 2014
Problem 1
The decomposition of azeomethane (A : CH3 N = NCH3

Primer on Linear Systems of ODEs
Copyright Brian G. Higgins (2010)
Introduction
Linear systems of ODEs arise in the study of the dynamics and stability of nonlinear systems of evolution equations. Consider the following nonlinear evolution equation in Rn

Department of Chemical Engineering
and Materials Science
ECH 256: Chemical Kinetics and Reaction Engineering
Overview of Undergraduate
Chemical Reaction Engineering and Kinetics
Lecture 3:
Kinetics
Brian G. Higgins
Department of Chemical Engineering and
M

Department of Chemical Engineering
and Materials Science
ECH 256: Chemical Kinetics and Reaction Engineering
Overview of Undergraduate
Chemical Reaction Engineering and Kinetics
Lecture 2:
Energy Equation for Reactors
Brian G. Higgins
Department of Chemic

Department of Chemical Engineering
and Materials Science
ECH 256: Chemical Kinetics and Reaction Engineering
Overview of Undergraduate
Chemical Reaction Engineering and Kinetics
Lecture 1:
Balance Laws for Reacting Systems
Brian G. Higgins
Department of C

Analysis of Surface Reaction in a Cylindrical Pore
BGHiggins/UCDavis/Mar_09
Introduction
We consider a gaseous species A that diffuses along cylindrical pore with radius r0 and undergoes a heterogeneous isomerization
reaction at the surface of the pore.

Analysis of Surface Reaction Mechanisms
BGHiggins/UCDavis/Mar_09
Background
Consider the following surface mediated reaction on a catalytic surface
A +B C
(1)
The following mechanism is proposed
k1
Ia : Adsorption Step : A + Os As
k2
(2)
(3)
Ib : Desorpt

Reaction-Diffusion in a Catalyst Pellet
BGHiggins/UCDavis/Mar_09
Background
We consider steady state diffusion in a spherical catalyst pellet. We showed in previous notes that the reaction-diffusion process
within the interstices of the pellet can be des

Method of Volume Averaging for Catalyst Pellets
BGHiggins/UCDavis/Mar_09
Method of Volume Averaging
Suppose we have a porous catalyst pellet that has a characteristic length scale of L0 . This might be the diameter of typical
catalyst pellet. Next we con

Film Theory for Multicomponent
Diffusion with Heterogeneous
Reactions
BGHiggins/UCDavis/ECH256/Mar_09
Film Theory
The film model of diffusion assumes that all the resistance to mass transfer occurs in thin stagnant layer of
fluid adjacent to some phase bo

Exploring 1-D Evolution
Equations:
Steady States and Stability
BGH/UCD/Feb_09
Introduction
In this brief tutorial we examine the 1-D evolution equation
U
t
= F Hm, UL = U Im - U - U2 M,
U H0L = U0
(1)
The equation is said to be autonomous when the indepen

The Batch Reactor: A Primer
BGH/UCDavis/Feb_09
Introduction
In these notes we analyze the batch reactor from different view points. For convenience we will assume our batch reactor has
fixed volume. Then starting with the species balance and integrating o

Diffusion Flux
BGHiggins/UCDavis/Jan_07
Introduction
Suppose we are given two expressions for a molar diffusion flux relative to the velocities w ' and w '
J1 = ck Hvk - w1 L
k
J2 = ck Hvk - w2 L
k
(1)
In this notebook we will develop the appropriate form

Basic Concepts in Mass Transfer
BGHiggins/UCDavis/Jan_07
Introduction
In this notebook we review the various concentration definitions that are used extensively in solving mass transfer
problems, especially when we are dealing with a mixture containing mu