New Biodiesel Fully Compatible with Conventional Engines

Researchers at the University of Kaiserslautern have solved a problem that has long plagued biodiesel: incompatibility with conventional diesel engines. Until now, biodiesel could not be used undiluted in a conventional diesel engine since its boiling point is higher than that of petroleum diesel, causing it to leave deposits on engines. (Much of current biodiesel is produced from rapeseed, which is shown growing in the picture above). But now there is a solution, with a newly designed biodiesel that burns cleanly without buildup, even when used completely undiluted in a conventional diesel engine.

The researchers have developed a way to treat biodiesel to bring about compatibility. With virtually no energy input, they convert a mixture of plant-derived fatty esters and bio-ethylene into fuel. The particular advantage of this new technique is that the researchers are able to precisely adjust the chemical properties of the mixture.

The researchers combine two catalytic methods to transform the long-chain fatty esters into a mixture of compounds with shorter chains. This process changes the ignition and combustion properties of the biodiesel. Combustion starts at lower temperatures. The two methods were synchronized with each other using mathematical simulations.

For more information about this breakthrough, see the researchers' published work in Science Advances.