Designing Water Consequences (2008) : activated carbon 'ice cubes'

Activated carbon, with its micropores some 10,000 times smaller than human hair, can absorb impurities in water. They are what many water and air filters contain. A block of wood carved into the shape of ice cubes are burnt to create the activated carbon. Instead of the usual melting and infusion by normal ice cubes, these carbon ice cubes absorb impurities from your glass of drinking water.