Accidentsarising fromoil spills cause serious environmental and ecological problems every year. Various approaches, including in-situ burning, mechanical skimming, dispersant-aided diffusion, have been employed to fight against oil spills. Among the existing methods, physical adsorption of oil by porous material is a simple and efficient technique. However, this method is ineffective for viscous oil, like the crude oil which exhibits yoghurt-like state at room temperature.

A team led by Professor Peng-Cheng Ma in the Xinjiang Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, developed a new type of oil gelator using biodegradable wheat bran as a starting material. The gelatorcanselectively congeal oil spills into floating gels on water surface, thus preventing oil film from spreading and providing convenience for easy collection (Figure 1).The researchers studied the mechanism behind such interesting observation, and found that the developed wheat bran contains lipophilic parts, resulting in the adsorption of oil droplets inside the material. On the other hand, the hydrophilic component in the wheat bran, like the hydroxyl groups on its surface, provides a way for the formation of hydrogen bonds among the bran particles as well as with water molecules, thus preventing the scattering of gelator with adsorbed oil on water surface. The synergy of the above two aspects made the material an excellent oil-gelling performance, i.e., the aggregation induced gelation (AIG), in macro-scale.

With advantages like easy applicability, excellent phase-selectivity, short gelling time, and green process for the preparation, the wheat bran demonstrates its remarkable potential as an effective terminator for oil spills.