Umeå UniversityUmeň University - Chemistry Courses in English

Process Analytical Chemistry D, 5 p

Aim of the Course

Its the purpose of the course to show how chemical analyzer systems and chemometrics can be applied for monitoring, optimization and control of chemitechnical processes. Such applications may aim towards increased conversion and product quality as well as improved occupational and environmental conditions. The course curriculum covers non-invasive measurement methods, sampling strategies and on-line sample pretreatment techniques. Chemical analyzer systems, based on spectroscopic, chromatographic, physical and electrochemical principles, are studied with regard to their possibilities and limitations in industrial applications. Process chemometrics, including multivariate calibration, spectral curve resolution, time series analysis and statistical process control, is an essential part of the course.

Course Contents

Background knowledge
Time plays an important role in PAC. Therefore the course starts with a brief introduction to the dynamics of chemical processes, chemical reactors and analyzer systems.

An understanding of flow mechanics is crucial for design of sampling and sample transport systems. Therefore flow mechanics is introduced with special attention given to problems associated with representative sampling of particles in continuous flow systems.

Analyzer systems
Systems for chemical process analysis have been categorized based on their proximity to the process stream: The course treats (1) non-invasive chemical measurement methods which sometimes produce a 2D or 3D image of the reactor interior, (2) in-line methods where a sensing probe is placed in the process stream and (3) off-line methods where a sample is taken out and brought to the analyzer. The first group includes several spectroscopic techniques, e.g. UV-VIS-NIR-IR and Raman spectrometry. In-line methods are commonly based on electrochemical and optochemical sensors, the latter usually combined with fiber optics for conduction of radiation from and back to a remote source/analyzer system. In the last group we find analytical instruments designed for the laboratory environment or modified to endure unattended operation for long periods of time in a harsh industrial environment. In general a compromise is sought between accuracy and precision on one side and adequate response time and reliability on the other. The course gives an overview of those key technologies and strategies for their application.

Chemometrics
Methods for multivariate calibration and multivariate classification are studied as a means to derive quantitative information on quality variables (e.g. concentrations, octane ratings, etc.) from several measured variables (e.g. absorbances at different wavelengths, responses from sensor arrays, etc.). Special attention is given to visualization of data, outlier detection, calibration transfer between instruments and reduction of the number of measured variables.

Techniques for resolving the individual spectral curves for the components of a mixture are studied with regard to their applicability for qualitative analysis, i.e. identification of unknown compounds from their spectra.

Time series analysis and methods for multivariate statistical process control are introduced.

Laboratory Exercises
Presently the students are given the opportunity to get practical experience from the following exercises:

  • Determination of phosphates in water using flow injection analysis and multivariate calibration. Application to wastewater treatment.
  • Fast chromatography with unresolved peaks and multivariate calibration. Application to analysis of o-difenols in black liquor from pulp production.
  • Simultaneous NIR-spectroscopic determination of the temperature and concentrations of components in a mixture of alcohols and water.
  • Isokinetic sampling of particles in a stream of air.
  • Analytical problems associated with bioreactors: sampling, chemical sensors and automation of analysis procedures for proteins.

Further exercises are under development encompassing, for example:

  • Spectral curve resolution.
  • Sampling using membrane filtration.
  • Sensors based on fiber optics.
  • Electrochemical biosensors.

Case studies
A series of invited lectures is given by workers with practical industrial experience with PAC applications.

Visits are made to industrial and municipal plants where PAC installations and problem solutions are studied.

PAC applications reported in the litterature are critically examined and discussed in a series of seminars.

In the future, PAC problem solving will be an essential part in the course. The students should then work with real PAC problems presented by persons with relevant industrial experience.

Compulsory laboratory experiments are included in the course.

Course Dates 1998/99

  • November 2, 1998 to January 17, 1999. Full time course.
  • March 22 to June 6, 1999. Full time course.
Required Qualifications

Literature

  • Multivariate pattern recognition in chemometrics, illustrated by case studies. Richard G. Brereton (ed.), Elsevier, 1992.
  • Compendium on process analytical chemistry (in preparation).
Other Advanced Level Courses in Analytical Chemistry and Chemometrics

For more information, contact one of the course teachers:

Principal teacher: Anders Ohlsson
Umeň University, Department of Chemistry, Analytical Chemistry, S-901 87 Umeň, Sweden.
Phone: int+46 90 7865481 / Fax: int+46 90 136310 / e-mail: keao@alchemy.chem.umu.se

Chemometrics teacher: Paul Geladi
Chemometrics Group at Department of Chemistry, Umeň University, S-901 87 Umeň, Sweden.
Phone: int+46 90 7866917 / Fax: int+46 90 136310

You can also contact the Department of Chemistry by
Phone: int+46 90 7865238/7865173/7865262, or Fax: int+46 90 136310/167655.

Department of Chemistry Home Page

This document was last updated on April 7, 1998.
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