Self-cleaning Clothes with TiO2

It’s a fact of life: your clothes get dirty and smelly and they need to be washed. But Reedies, we all know, are strapped for time, so sometimes its just easier to stretch out those visits to the laundry room (at least until your friends start avoiding you). What a boon it would be to college life if your clothes would keep themselves clean instead. Your favorite black t-shirt would always be there for you. More importantly, clothes that clean themselves would save the community a large amount of water and energy, and would reduce problems associated with detergent manufacture and disposal (those suds have to go somewhere!).

Daoud et al. (Chem. Mater., 2008, 20(4), 1242-1244) describe a technique that they have developed for chemically bonding nanocrystals of titanium dioxide (TiO₂) to keratin fibers. TiO₂ is a well-known photocatalyst (and a major constituent of white paint), and Daoud et al. show that the TiO₂-treated fibers can decompose dirt, stains, and even inhibit bacterial growth, when exposed to sunlight.

Perhaps one day soon, college students will be able to do their laundry just by going for a walk in the sun.

Greener Gasoline with gamma-Valerolactone (GVL)

Organic chemistry students learn that gasoline is a blend of linear and branched hydrocarbons, a fact that is recognized by a gasoline’s “octane” rating. Less time is spent discussing “oxygenated” fuels created from additives like ethanol and methyl tert-butyl ether. These fuels are desirable because they have higher octane levels and burn more cleanly. (Ethanol, of course, is also used as a gasoline substitute.)

Horvath et al. (Green Chem., 2008, 10, 238-242) now report that γ-valerolactone (GVL) might be a greener fuel additive than either alcohols or ethers. Unlike the other compounds, GVL doesn’t attract water (non-hygroscopic), it has a relatively low vapor pressure (thus limiting VOC-derived air pollution), it possesses a relatively high flash point and low melting point, and it doesn’t easily form peroxides upon standing in air (these properties facilitate safe storage and transport). GVL is produced by fruit, so large-scale use by drivers would require the development of another source, and the team examines the possibility of converting sucrose to GVL.