Course Project

General Instructions

  1. This project comes in three separate, but related, parts. The first part of the project is to be a solo effort. The second and third components will be group efforts.
  2. Here's the basic idea. First, you will find an engineering or scientific application of differential equations. The second component calls for the group investigation of a specific application of ODEs in chemical engineering. Each group will then choose one of their individual projects for analysis; this is the third and final part of the project.

  3. The report for each part of the project is worth 30 points. The distribution of these points will be

    The remaining points are based on the prompt selection of group members (5 points) and a brief summary of the group experience (5 points).

Part I -- Design Your Own Project

Part 2 -- Consecutive Reactions in a Batch Reactor

Part 3 -- Analyze Your Own Project

One-Page Project Outline

TITLE: Consecutive Reactions in Batch Reactors

NAME: Doug Meade

FACULTY CONTACT: Prof. Ralph White, Chemical Engineering (ECHE 430)

PHYSICAL DESCRIPTION:

Consider a reaction involving three substances, A, R, and S, which have first-order reaction rates and are carried out isothermically in either the gas or liquid phase in a perfectly mixed batch reactor. The reaction begins with a pure sample of component A.

Schematically, the process can be represented as:

where is the reaction rate for the conversion of A into R, is the rate at which R is converted into S; and are the concentrations of A and S, respectively.

The primary objective is to determine the amount of each substance in the reactor up to time after the reaction starts. Additional information that is desired includes the time at which the amount of substance R is a maximum, the time at which the amount of S exceeds the amount of A, and the total amount of substance S produced at any time t>0.

MATHEMATICAL FORMULATION:

This is really just a three-compartment container problem. Looking at the inflow and outflow for each substance leads to a system of three first-order differential equations with initial conditions.

Let , , and denote the number of moles of A, R, and S at any time in the reactor. The volume of solution in the tank is assumed to be constant. Then, conservation of the total amount of each of the three components can be expressed as

with initial conditions , , . This system can be solved using the ideas for first-order linear ODEs.

Once the solution is obtained, answers to the specific questions can be obtained as follows:

A graph will be used to show the number of moles of each component as a function of time.

DATA:

Two different set of parameter values are , and , . With these parameters it will be possible to see some of the differences that arise between the cases and . Using will be useful in investigating any differences that occur when .

REFERENCES:

C. D. Holland and R. G. Anthony, Fundamentals of Chemical Reaction Engineering, Prentice--Hall, 1979.





Douglas B. Meade
Last revision: Wed Feb 8 14:04:33 EST 1995