This evening I heard John Meurig Thomas giving the Bragg Lecture at the Royal Institution – Highlights of Journeys into the Architecture of the Invisible. It was a combination of reflections on his career and his indebtedness to various colleagues, for example the Braggs, then moving on to his work on solid catalysts using such techniques as X-ray diffraction and spectroscopy, magnetic resonance spectroscopy, and high resolution transmission electron microscopy (there’s the succinctly named High-Angle Annular Dark-Field Scanning Transmission Electron Microscopy, or HAADF STEM for short).
Some interesting facts about catalysts that were given – they’re high area nanoporous solids, full of shape selective holes; 1g of catalyst can have a surface area of 1000m2, and the length of channel within it can be150 million km. Catalysts can last for years – the best ammonia catalyst lasts for 14 years.
A solid catalyst, which you can hold in your hand, can be as acidic as concentrated sulphuric acid. And there’s a glut of bioethanol, but it can be dehydrated using a catalyst to make ethylene.
Apparently nylon manufacturing produces large amounts of waste chemicals – for example, 3.8kg of ammonium sulphate per 1kg nylon produced – and some of the materials used in its manufacture are pretty nasty – but using a new catalyst there’s no waste products. This is what the new catalysts are good at, producing many things (including foods, pharmaceuticals, fabrics, fuels, and plastics) and reducing the use of nasty chemicals, so they’re safer and better for the environment, and manufacturers like them because a reduction in ingredients mean less cost.
It was a most enjoyable talk – low-key but full of facts, a mixture of reminiscences and science.