Shape and control — it's crystal clear

An international collaboration led by Michael Anderson at Manchester University is embarking on a project to control the growth of zeolite crystals — non-porous materials used commercially in catalysts for cracking oil.

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,' Anderson explained. 'The pores can run through the crystals in a number of different ways — in one direction, like tunnels running through from one side to the other, in a 2D network, or in 3D, running all through the crystals.'