Breakthrough Technology by Czech Scientists Utilizes Biodiesel Production Waste and Improves Fuel Properties

A graphene-based biomaterial developed by Czech researchers could replace the acids traditionally used to convert glycerol – a waste product from biodiesel production – into useful fuel additives. Unlike conventional acids, the new material is non-toxic and fully recyclable. The discovery, made in cooperation with Indian scientists, was recently published in Nature Communications (1).

While the production and use of biofuels remain a hot topic – and often a controversial one – global consumption is rising rapidly and is expected to grow further in the coming years. That’s why it's crucial to optimize biofuel production processes. Biodiesel, an eco-friendly fuel derived from vegetable oils, significantly reduces toxic gas emissions when blended with conventional diesel. However, its production generates glycerol (or glycerin), a by-product also used in automotive antifreeze.

“Our goal was to find a way to convert glycerol into a chemical form that could be reused in the biofuel sector,” explained Radek Zbořil, researcher at CATRIN-RCPTM, Palacký University Olomouc, and head of the Materials-Environmental Laboratory at CEET, VSB – Technical University of Ostrava."We developed a carbon material based on graphene that is chemically modified using a natural amino acid.”

This eco-friendly material accelerates the conversion of glycerol into a high-value compound with unprecedented efficiency. “The resulting alcohol, known as solketal, significantly improves fuel quality and octane rating when added to fuel, while also reducing harmful micro-particle formation and emissions of carbon monoxide and other toxic organics. Additionally, it increases the viscosity and stability of biofuels, which is crucial for long-term storage,” said Aby Cheruvathoor Poulose of CATRIN, lead author of the publication.

Researchers in Olomouc have long been developing new nanomaterials derived from Nobel Prize-winning graphene, including in prestigious ERC-funded projects. In this study, anchoring a simple amino acid to the graphene structure proved to be the key.

“Both experimental and computational studies showed that this amino acid significantly increases graphene’s ability to attract reactive components — in our case, acetone and glycerol — to its surface,” added Aristeidis Bakandritsos, affiliated with both CATRIN and CEET. The new biomaterial is significantly more efficient in converting glycerol than commonly used industrial acids, such as sulfuric or hydrochloric acid, and unlike them, it is environmentally friendly.
“It also enables precise control of the chemical transformation toward producing useful biofuel additives without generating secondary waste,” Bakandritsos noted.

In 2021, the global biofuels market exceeded $110 billion and is expected to nearly double by 2030 (2). While biodiesel can be used directly in diesel engines, it is mostly blended with fossil diesel.
Approximately 40 billion tons of waste glycerol are generated each year during biodiesel production — its reuse represents a major challenge, particularly from a circular economy perspective.

Despite the increasing use of biofuels, critics – especially in the EU – have raised concerns about food resource consumption and environmental impact. For instance, rapeseed oil used for biodiesel results in CO₂ emissions throughout the processing chain — from sowing to oil refining — making the overall carbon footprint reduction far from ideal.

“I personally support the development of truly carbon-neutral and sustainable fuels, particularly hydrogen-based ones derived from renewable sources — a field we are also actively researching (3),” said Zbořil. “Still, biodiesel production cannot be ignored. On the contrary, it needs to be improved. Our material not only repurposes waste glycerol but also proved highly effective in pilot tests of biodiesel production from vegetable oils, including used cooking fats. We plan to continue our research and focus on more efficient conversion of waste oils for the development of second-generation biofuels, aiming for a production process that is both energy- and eco-efficient without harming agricultural landscapes.”

Photo: Martin Pykal

Sources:

Nature Communications article
Global biofuels market size – Statista
SAN4Fuel – Sustainable Fuels Project