Supercritical Solvent Comes Into Its Own

Chemists have long thought that liquefied, or ”supercritical,“ carbon dioxide could be the perfect, environmentally friendly solvent: It's essentially harmless to living things—and cheap. But it's also so inert that few substances will dissolve in it. Now, however, as reported in this issue on page 2049 , researchers have devised a surfactant—a sort of soap—that should help carbon dioxide dissolve a host of greasy compounds that are important in industry.