Joel Pawlak, an associate professor of forest biomaterials at North Carolina State University, has developed a material similar to foam rubber that absorbs water and attaches to molecules dissolved in it, leaving pure and potable water behind.
The material is a combination of hemicellulose and chitosan. The first comes from wood and is extracted by the ton in the paper-making process. Chitosan is extracted from ordinary crustacean shells — primarily crab, shrimp and lobster — by treatment with hydrochloric acid and then sodium hydroxide."
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