The Alarmist by Dave Lowe

Author:Dave Lowe [Lowe, Dave]
Language: eng
Format: epub
ISBN: 9781776564187
Publisher: Victoria Up
Published: 2021-09-15T00:00:00+00:00

CHAPTER 11

A TALE OF SERENDIPITY

My search continued for a technique to determine low levels of atmospheric formaldehyde. The handwritten lab books I used during those first few weeks record day after day of frustrating failure, and it became clear that the HPLC technique was never going to show the sensitivity we needed.

One night on an HPLC training course in Darmstadt, a city about 300 kilometres from Jülich, I sat in my hotel room in familiar despair. I thought back to the years I’d spent overcoming other obstacles. For no apparent reason my mind wandered back to an early student experiment where we had increased the efficiency of a simple alcohol distillation using some strange glass rings; were they called Raschig rings?

Suddenly I had an idea – the efficiency increase must have been due to the very large surface area on the rings. I grabbed a piece of paper and quickly calculated that even a small volume of rings could provide a large surface area for sampling low concentrations of a gas like formaldehyde. Inspiration comes calling at the strangest of times. By taking a step back from the techniques I’d been pursuing and using something like those weird rings to trap the formaldehyde from huge air samples directly into a sampling solution, I realised I might be able to avoid the terrible wet chemical technique. I stayed up late making calculations and checking the chances of contamination or random errors. That night, I couldn’t sleep. I got up a couple of times in the early hours and redid my calculations; the results were the same. Everything looked really promising and I couldn’t wait to get back to the lab.

When I returned to Jülich and told Ulrich about my idea, he was immediately interested. Thankfully, and perhaps as no surprise given the chemical engineer who’d invented Raschig rings was German, the stores at the KFA had a large selection of them. I lost no time designing an air sampler based on upright glass cylinders filled with the rings bathed in a small volume of DNPH sampling solution. The glass blower at the KFA had already built similar vessels and he had no problem making one from a sketch I’d given him. As soon as he’d completed it, I set it up on a balcony at the back of the lab and, improvising, used a car vacuum cleaner to suck a whole cubic metre of air through the sampling solution in the Raschig rings.

Trembling, I extracted a syringe full of the solution and injected it directly into the HPLC.

‘Yes!’ I yelled. Ulrich came running into the lab.

‘Look,’ I said, pointing at the chart. ‘It’s an enormous formaldehyde peak.’

‘You got that from outside air with the new sampler you just designed?’ he asked. ‘This could be the breakthrough we’ve been looking for!’

When Dieter Ehhalt came into the lab that week, Ulrich and I were still getting to grips with the new technique. He was clearly very pleased, and congratulated us with a slap on the back.

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