An international collaboration led by Michael Anderson at
Zeolites make up around 30 per cent of laundry detergent powder, where their principal function is water softening, but most that are used industrially are synthetic. They are also used for separating gases — particularly air — and storing others, such as hydrogen.
Zeolite crystals are about a micron in size and their shape is crucial, but controlling the shape of the growing crystals is difficult. 'The pores are about the size of, say, a benzene ring,'
Many of the most important zeolites are one-dimensional but, said
'This gives very long tunnels running though the crystal, which easily become blocked,' he said. 'Ideally, what you want to is engineer crystals that are short and squat, with the pores still in one dimension, but running through the crystal's short axis.'
By looking at how the crystals grow, the team hopes to be able to modify the way they are formed.
'We will be using techniques such as atomic force microscopy and high-resolution electron microscopy to watch them grow in situ on an atomic scale,' said
He believes another potential application could be to make zeolites containing spiral pores. 'In principle, these would be very good for chiral catalysis, making molecules of one-handedness,' he said. 'This would be very important for the pharmaceutical industry — if we could lock the chirality into the inorganic zeolite, we could use it as a template for stamping out chiral organic molecules.'