STALKS and leaves left over after hops are harvested could help decontaminate
watercourses and industrial waste water polluted with heavy metals.
Around 100,000 tonnes of hops are grown annually for the brewing industry
worldwide, but only the cones are used to make beer. Kirk Tiemann and his
colleagues at the University of Texas at El Paso took the stalks and leaves,
which usually go to waste, mashed them up, and mixed them into a silica-based
polymer.
They then packed granules of the polymer containing chunks of hop waste into
a glass column through which they pumped water containing several…
