Particle Size Measurements

Following my graduation in physical organic chemistry at the University of Amst- dam, I started to work at the Royal Dutch Shell Laboratories in Amsterdam. My first assignment was research in the field of detergents and industrial chemicals. It was followed by development work on thermal wax cracking for production of C - C 2 14 olefins and on acid-catalyzed synthesis of carboxylic acids from C - C olefins. 3 6 Then, I made a significant change to analytical chemistry, first at Shell's process development department and later in the chemical engineering department of Delft University of Technology. In both departments, there was a large variety of analy- cal techniques and development of new methods for automated analysis of small process streams. It was the time that gas chromatography conquered the world. In this field, a firm basis was given by Henk Boer, Arie Kwantes and Frits Zuiderweg at Shell Research Laboratories in Amsterdam, both for packed and for capillary c- umns. The potential of gas chromatography was huge and, therefore, also in Delft, its use increased enormously. Moreover, the growth of this technique was facilitated significantly by the rapidly developing electronics industry. It not only led to digital peak integrators and personal computers but also enabled complex measurement techniques. In addition, I became involved in surface area and porosity characteri- tion of catalysts and adsorbents, on which topic the research had been initiated by Prof. J. H. de Boer.

The author has been working at the Delft University of Technology for about 35 years, the last 20 years of it in Particle Characterization in the Particle Technology Group of prof. Brian Scarlett. Also, for about 15 years he has been a member of ISO/TC24 on Sieving and Other Methods for Particle Size Measurement and he still is. Retired now the author is active in giving courses on this subject, in the Netherlands as well as in Sweden and the United Kingdom.