Imagine, if you will, a slick black surface extending as far as the eye can see, where once-clear water now laps sluggishly and dead fish float. This is the reality imposed upon our environment by oil spills, the disastrous result of many oil-tanker or oil-rig accidents. When a large amount of oil is leaked out into the ocean, it can form a coat on top of the water's surface that poisons and smothers sea creatures—especially those that live on the surface of the water.
The oils that are spilled into our world’s seas can come in many different varieties, all of which are absorbed by a material developed recently at the Wisconsin Institutes for Discovery. This super absorbent, oleophilic aerogel takes in crude oils and organic solvents, as well as heavy metal ions. All of these contaminants are absorbed into the aerogel while water is repelled. Because of these particular properties, the patent-pending aerogel has enormous potential as a water-purification tool.
Animals that live on or near the surface of the sea, such as sea otters and pelicans, are affected most drastically because their environments are most directly saturated with oil. Lighter oils such as gasoline evaporate more quickly, so they do not require as much cleanup as the heavier oils, but they are much more toxic and directly harmful to wildlife. The heavier oils have more capacity to smother or interfere with body-temperature regulation, as they thickly coat furred, feathered, or fish-like organisms. Both types of oil have unwanted effects on the environments into which they are spilled, and many different methods of cleanup are used to deal with these spills.
According the EPA's website, a sorbent is anything that uses the method of adsorption or absorption to recover liquid. Natural organic sorbents can absorb between three and 15 times their weight in oil. Natural inorganic sorbents are a bit better; they have the capacity for four to 20 times their weight in oil. The material developed by the three-person team of Shaoqin “Sarah” Gong, Qifeng Zheng and Zhiyong Cai has the capacity to absorb 96 times its own dry weight in contaminants. This incredible absorbency could be put to good use cleaning up oil spills and returning environments to their natural states more quickly.
The material itself is made through a variety of chemical processes, one of which takes the liquid component out of a pre-existing gel matrix and replacing it with gas. If this process can be completed while maintaining the stability of the gel structure, you get an aerogel. The freeze-drying process of creating this particular aerogel is environmentally friendly.
Awareness of our own environmental impact is the impetus for creating technologies such as this for dealing with the problems that we have made. The aerogel created at the Wisconsin Institutes for Discovery represents a step forward in the worldwide push to develop cleaner and better solutions to pollution.