New polymer could purify water in seconds

Scientists have developed a new reusable polymer that can remove pollutants from flowing water within seconds, just like air fresheners trap invisible air pollutants in the home and remove unwanted odours.
Researchers have used the same material found in air fresheners, cyclodextrin, to develop a technique that could revolutionise the water-purification industry.
The team, led by Will Dichtel, associate professor at Cornell University in US, developed a porous form of cyclodextrin that has displayed uptake of pollutants through adsorption at rates vastly superior to traditional activated carbon - 200 times greater in some cases.
Activated carbons have the advantage of larger surface area than previous polymers made from cyclodextrin - but they do not bind pollutants as strongly as cyclodextrin.

"What we did is make the first high-surface-area material made of cyclodextrin combining some of the advantages of the activated carbon with the inherent advantages of the cyclodextrin," Dichtel said.
"These materials will remove pollutants in seconds, as the water flows by," he said.

The cyclodextrin-containing polymer features easier, cheaper regeneration, so it can be reused many times with no observed loss in performance.
Recyclability is another advantage of the cyclodextrin polymer, Dichtel said. Whereas activated carbon filters must undergo intense heat-treating for regeneration, cyclodextrin filters could be washed at room temperature with methanol or ethanol.
The findings were published in the journal Nature.