chemical engineers" who changed the world"-part1

                                                         Upping the octane 
                                  Vladimir Haensel

To many an engineer the phrase “It cannot be done”  is like a red rag to a bull. Vladimir Haensel, process research coordinator with UOP, was no exception. Haensel was working on petroleum cracking and looking for ways of increasing the octane rating of the resulting fuels – at the time, in 1941, an octane rating of 65 RON was the norm. Such a low octane rating makes a fuel very likely to combust prematurely, causing serious engine knock – which in turn makes it impossible to use efficient high-compression engines.

Haensel was looking for a suitable catalyst for the cracking process and was convinced that platinum would be perfect for the job. Except, of course, that platinum was extremely rare and prohibitively expensive – “it cannot be done” was the received wisdom.

But what, thought Haensel, if he could make do with a vanishingly small quantity of platinum? What if on top of that he could regenerate any fouled catalyst in situ, allowing him to – in theory at least – run the process indefinitely?

His refusal to accept conventional wisdom led to the creation of a heterogeneous alumina-supported platinum catalyst that would very effectively dehydrogenate the hydrocarbons in the C6–C10 paraffins and transform the resulting unsaturated hydrocarbons into nice aromatic rings. By working with a highly-dispersed catalyst with extremely small platinum particles, Haensel managed to reduce the platinum content in the catalyst to as little as 0.01%. The so-called ‘platforming’ (platinum reforming) process was born.

The first platforming unit started up in 1949 and is still very much with us – some minor improvements aside. Today the vast majority of our fuels are produced through a platforming process. Without Haensel’s determination, we could say goodbye to today’s supercars and hello to the backfiring smoke-belching cars of the 1930s.

                              Plastic fantastic

         Reginald Gibson, Eric Fawcett, Michael Perrin                                                                                                                       

Polyethylene (PE) is everywhere. From shopping bags to Tupperware boxes, from plastic toys to water pipes and even hip replacements, it’s PE’s versatility that makes it the world’s most common plastic.

Its commercial success came courtesy of two ICI chemists, Reginald Gibson and Eric Fawcett, who in 1933 experimented with ethylene and benzaldehyde at high pressure. The reaction yielded a mysterious waxy solid but the reaction was fickle – attempts to reproduce it would as often as not result in a very loud bang and a mixture of hydrogen and carbon. Nobody could work out initially why the experiment would result in these quite spectacular failures, and ICI eventually decided to stop the research before someone came to serious grief.

It later transpired that the key to making the experiment work was oxygen: if there’s too little, nothing happens, too much and the mixture explodes. It had been pure luck that some of the ethylene bottles used in the early experiments had been contaminated with just the right amount of oxygen. 

With high-pressure chemistry still in its infancy, there was little off-the-shelf equipment, and it fell to the team’s resident engineer, Dermot Manning, to design and build most of the reaction vessels. A key problem was sealing the vessels, as the standard lens ring would not hold gas at pressures above 300 atm – and ICI wase working at well over 1,000 atm here. Manning devised a self-sealing wave ring, which used the rising internal pressure to seal the wavy circumference of the ring into its seat, which overcame the problem.

Full-scale production of PE started the very day Germany invaded Poland, and a polymer that had been destined for telecommunications cable was used to insulate airborne radar instead. This proved to be an important advantage, as it enabled the British forces to create a radar system that was light enough to place on fighter planes, which helped their supply ships avoid German submarines.

                                                 Fuelling a way of life 

Donald Campbell, Homer Martin, Eger Murphree                                                                                                      and charles Tyson

        Modern life runs – quite literally – on the products of a fluid catalytic cracking unit. Our cars run on petrol, the planes on jet fuel, we pick up our food from the supermarket (or bring it from home) wrapped in polyethylene film and wash it down with drinks from a polycarbonate bottle, while standing on a polypropylene carpet.

Yet this ubiquitous feedstock of modern life in all its aspects would be a lot rarer – not to mention a great deal more expensive – if it wasn’t for the workhorse of the refining industry, the fluid catalytic cracking (FCC) unit.

Some 400 FCC units are in operation around the world today. And each and every one of them can trace its ancestry back to one such unit, the Model I FCC, which started up in Baton Rouge, Louisiana, on 25 May 1942.

The 17,000 bbl/d unit was largely the brainchild of four chemical engineers, known as “the four horsemen”, working for the New Jersey company Standard Oil. They were Donald Campbell, Homer Martin, Eger Murphree and Charles Tyson.

The four developed today’s modern  FCC process largely because their employer (and several other companies) did not want to pay the hefty $50m licensing fee for another early catalytic cracking process, developed by the French engineer Eugene Houdry and the pharmacist EA Prudhomme. But while the Houdry process was a semi-batch process using a fixed-bed catalyst, the real breakthrough for the “four horsemen” (and their advisors at MIT) was to realise that under certain circumstances, a powdered catalyst could behave like a liquid. This paved the way for the continuous process that was so efficient that it not only rapidly outcompeted the Houdry process, but remains in continuous use 60 years on.

                        Pfizer’s penicillin pioneers

                     Jasper Kane and John McKeen

Sometimes it’s not the innovation itself that matters – it’s making it available in quantity and at the right time. Scale-up, in other words.

Ensuring that there was sufficient penicillin to treat the hundreds of thousands of soldiers that took part in the D-Day landings during World War II was not the work of Alexander Fleming; it was chemical engineers who made that happen. While many worked on scaling up production of penicillin, it was Pfizer chemist Jasper Kane and chemical engineer John McKeen who arguably made the biggest contribution.

The two cracked the problem of production via deep-tank fermentation. Since penicillin requires air to grow, the biggest problem was designing an aerated, stirred tank that would reliably and efficiently produce quantities of the notoriously fickle drug.

War-time materials shortages forced Pfizer to take a huge commercial gamble on producing the drug: with no means of acquiring extra reactors, Pfizer had to re-configure units producing tried and tested cash products.

Factory manager John Smith was reluctant. “The mould is as temperamental as an opera singer, the yields are low, the isolation is difficult, the extraction is murder, the purification invites disaster and the assay is unsatisfactory. Think of the risks and then think of the expensive investment in big tanks – think of what it means if you lose a 2000-gallon tank against what you lose if a flask goes bad. Is it worth it?”

It is to the credit of Kane that he did not back down, and convinced his bosses to do the right thing and take the commercial gamble. And it is to the credit of McKeen and his team, who worked sixteen hours a day, seven days a week, to complete the scale-up in just six months. The D-day landings alone saw 150,000 soldiers treated with penicillin, and 90% of the doses supplied were supplied by Pfizer.