Nanoparticles could give biofuel a boost, but at a cost

Indian researchers found that addition of a nanoparticle catalyst to biofuel could improve the performance of the fuel, making it burn cleaner.

The study, published in the Journal of Renewable and Sustainable Energy shows aluminum oxide nanoparticles could act as a catalyst; making the fuel burn more efficiently and more cleanly. The high ratio of surface to volume of these tiny particles (average diameter of 51 nanometers) creates a large reactive surface for the reaction to take place on and also improvies the air-fuel mixture leading to more complete combustion. When combustion is incomplete, carbon monoxide and a range of other harmful gases are produced in greater quantities. Aluminum oxide is often used as a catalyst in the chemical industry, its use in nanoparticle form is relatively new and unusual.

Study author R. B. Anand, at National Institute of Technology in Tiruchirappalli tested the nanoparticles on jatropha-derived biofuel, blending the nanoparticles into the fuel using a detergent. In trials, the nanoparticle-biofuel burned more fully, massively reducing the emitted amounts of gases such as carbon monoxide and nitrogen oxide (a potent greenhouse gas) and also less smoke. He is currently testing different blends of particles in an attempt to find an ideal proportion, one that balances the performance boost with cost. He is also investigating the effect that nanoparticles have on the rest of the engine and also the potential of other nanostructures as fuel enhancers.

The researchers are now testing other types of nanoparticles, including hollow carbon nanotubes, and investigating the effects of nano-additives to engine lubrication and cooling systems. One obstacle to the application of this kind of nanotechnology is the high cost of nanoparticle production, says Anand -- who also cautions that nanoparticles "should be used judiciously," because they tend to "entrain into human bodies."