Being a researcher at DSM at the time, the appointment of Jan Fortuin at the University of Amsterdam in 1976 was of scientific significance since the field of Process Technology had yet to be developed at the interface between industry and academia. Jan was a Process Technologist through and through. He had witnessed the emergence of that branch of science up close after World War II and had been part of it ever since his education at TU Delft.

Jan was one of the true pioneers of the field and his working life spanned the period of the ‘old school’ analytical approach up to the emergence of process modelling software such as ASPEN flowsheeting. In the standard series on ‘The history of chemistry in the Netherlands’ he described his experiences and views in part 3 on ‘The development of chemistry from 1945 to the early eighties’. He wrote chapter 4, titled ‘Process technology and chemical industry’, which can be considered his scientific testament.

Management by phone

In practice, the combined appointment at DSM as well as UvA meant that Jan often had to supervise the Amsterdam experiments by phone. At times this ‘remote control’ worked out somewhat hilariously; reports that everything went perfectly according to plan did not always match the reality of the lab… On his side, Jan was not always satisfied with the situation. In the monthly faculty magazine 'Uiltje van Pallas' (Pallas’ little owl) he was interviewed on his weekly travels back and forth from Geleen to Amsterdam. The article was headed with his sigh that at least "On the train, the telephone does not ring". A situation that is quite outdated today.

Jan’s group worked on a wide range of subjects, resulting in almost two dozen PhDs. An important focus was on two-phase flow in pipes and T-pieces. Other subjects were the absorption of gas in slurry reactors; the adsorption of water on aluminum surface; and catalyst particles on gas bubbles. In terms of devices, the pulsed packed column was a successful object of study. More fundamental research involved rheometry; heat and mass transfer in turbulent tube flow; and reduction of friction in turbulent flow (with polymers). Later came more model-based research on the dynamic behavior of continuous and batch reactors, which also involved more chemistry. He supervised PhD candidates until way beyond his retirement. The last one, in 1998, could not even formally obtain his PhD with him. His successor Piet Iedema was happy to take on that task. Jan’s last paper was published in 2003 (he was 76 at the time) in AIChE Journal, written together with his former co-worker Peter Hamersma: “Effect of drag reducers on transport phenomena in turbulent pipe flow”.

Jan also made an important contribution to the international development of Chemical Engineering. For twenty years, from 1972 until 1992, he was a secretary of the one of the Working Party (WP) on Chemical Reaction Engineering of the European Federation of Chemical Engineering (EFCE). People who worked with him remember his phenomenal memory for congress dates, places, and chairmen. In a review article in a 1992 issue of the journal ‘Chemical Engineering Science’, he not only describes the activities of the working party and important process technology discoveries, but he also mentions the associated people in an appreciative tone of voice. It characterizes him, being not only interested in science but also in people.

Amiable, passionate and meticulous

Jan is remembered as an amiable person, correct, polite and friendly. His passion and meticulousness about science could be demanding, expecting that a discussion in one week would lead to results or implementation the next. Some of his PhD students experienced writing their first scientific paper as a ‘baptism of fire’. It could take dozens of revisions, but instilled a perfect eye for mistakes and twists of thought. Famous were the PhD lunches in the nearby ‘Plantage’ that almost always resulted in a napkin scribbled full with Jan’s latest ideas for research. One of them remembers his supervisor as a very honest, patient, friendly, tenacious and sharp mentor that taught him the value of what is right, what is correct, what is scientifically substantiated. Co-workers remember how he would manually check mathematical (analytical) solutions of model problems obtained with a program such as Mathematica (Wolfram) to see if they were correct. He was also a strong proponent of the use of SI units (système international) and regularly insisted on their correct use.

After his emeritus status, Jan continued to visit the Amsterdam labs regularly, travelling from his hometown of Sittard. He always had an agenda that invariably included enthusiast conversations about his latest findings. These could be lengthy, especially when he was able to present an analytical solution to a problem that at first could only be solved numerically. This could be a test of patience but also serves as an indispensable reminder of the man he was.

An inspired scientist has passed away with Jan Fortuin, a solid and disciplined professional, a fine person, who also has an eye for the human side of science. Dear Jan, rest in peace…!

Piet Iedema, Renate Hippert

See also

Jan Fortuin in the UvA Album Academicum