The global consumption of biofuels is increasing dramatically and will continue to play a significant role in the coming years. Therefore, it is necessary to optimize the process of their production. Biodiesel is an eco-friendly fuel of plant origin, and its addition to diesel fuel significantly reduces emissions of toxic gases into the atmosphere.
However, during the production of biodiesel from vegetable oils, glycerol (also known as glycerin), which is commonly used in antifreeze mixtures for automobiles, is produced as a waste byproduct.
“Our goal was to find a way to convert glycerol into a chemical form that could be reused in the field of biofuels. We developed a carbon-based material derived from graphene and chemically modified using a natural amino acid,” explained Professor Radek Zbořil, Ph.D., Scientific Director of CATRIN – RCPTM (Regional Centre of Advanced Technologies and Materials).
The new eco-friendly material can accelerate the conversion of glycerol into a high-value compound with the highest efficiency achieved so far. “The resulting alcohol, known as solketal, significantly improves fuel quality and octane number when added to fuel. It also reduces unwanted formation of microparticles, as well as emissions of carbon monoxide and other toxic organic substances,” said the lead author of the publication, Aby Cheruvathoor Poulose.
Moreover, solketal increases the viscosity and stability of biofuel, which is important for the long-term storage of biodiesel.
The discovery, published in Nature Communications, is the result of collaboration not only among Czech scientists from the Czech Advanced Technology and Research Institute (CATRIN) at Palacký University in Olomouc and the research centers CEET and IT4Innovations at VSB – Technical University of Ostrava, but also with their Indian colleagues.
Scientists in Olomouc have long been working on the development of new nanomaterials derived from Nobel Prize-winning graphene, including through prestigious projects of the European Research Council (ERC). This time, anchoring a simple amino acid into the graphene structure helped achieve the desired result.
“Experimental and computational studies showed that this specific amino acid significantly enhances graphene's ability to bind reaction components—acetone and glycerol in our case—to its surface,” added Aristeidis Bakandritsos.
In 2021, the global biofuel market exceeded $110 billion, and it is expected to nearly double by 2030. Biodiesel can be used directly as an eco-friendly fuel in diesel engines, though it is most commonly blended into petroleum-derived diesel fuel.
Each year, approximately 40 billion tons of waste glycerol is generated during biodiesel production, and finding ways to repurpose this byproduct represents a major challenge—especially in line with the principles of the circular economy. The newly developed material not only enables efficient utilization of waste glycerol from biodiesel production, but in pilot experiments, it also proved exceptionally effective in the direct production of biodiesel from vegetable oils, including waste fats.
“That’s why we will focus on more efficient conversion of used waste vegetable oils to develop second-generation biofuels, aiming to make the entire biodiesel production process both energy- and environmentally sustainable,” Zbořil concluded.
Source: https://21stoleti.cz/2023/07/20/biomaterial-premeni-odpadni-glycerol-na-uzitecny-produkt/