Cotton is graded on several quality parameters, including fiber strength, length and micronaire (a measurement of the lint’s fineness and maturity). Cotton farmers strive to avoid low-mic cotton, which is generally unwanted by textile mills and therefore penalized in the marketplace, says Seshadri Ramkumar, manager of the Nonwovens and Advanced Materials laboratory at Texas Tech University.
"It doesn’t take a dye well, so it has little value as a textile fiber," he says.
But Ramkumar has other designs for low-mic cotton. In a recent study, Ramkumar and his colleagues tested low-mic cotton’s effectiveness of mopping up oil. The study, which was published in the most recent issue of the American Chemical Society’s journal, shows that one pound of low-mic cotton can absorb more than 30 pounds of dense crude oil.
"Because it is less mature, more of it can be packed into a given area," Ramkumar says. "We show through sophisticated testing that low-micronaire cotton is much finer and can pick up more crude oil."
Ramkumar says the natural waxiness of raw, unprocessed cotton fiber keeps water out. That makes cotton an efficient, effective, natural solution for cleaning up ocean-based oil spills.
Ron Kendall, director emeritus at Texas Tech’s Institute of Environmental and Human Health, says the explosion and subsequent oil spill on Deepwater Horizon in 2010 reinforces the needs to devise smarter oil-spill solutions.
"One of the things we realized from the Deepwater Horizon disaster is we didn’t have the best tools for cleanup, and the technology wasn’t right for the booms," he says. "This discovery that low-micronaire cotton, which is the least valuable cotton, can absorb as much crude oil as it does is a breakthrough discovery. It gives us an excellent tool for cleanup of shorelines, animals and ecologically sensitive areas, as well as a new technology for booms that can stop oil sheen moving into wetlands."
Graduate student Vinitkumar Singh conducted laboratory work for the study. Cotton Incorporated and the CH Foundation each contributed funds to the research.