Plant waste is everywhere, in harvested fields, forestry sites and processing plants. A new study argues it could play a bigger role in the energy economy if it can be processed in a cleaner way.

Prof Indra Bahadur, a chemist at the Mahikeng Campus of the North-West University (NWU), has published a review article in Chemical Reviews (Impact Factor 55.8), one of the leading journals in the field. The article examines how a class of liquids known as deep eutectic solvents could help break down plant waste more efficiently and with less environmental impact than just leaving it in piles.

At issue is lignocellulosic biomass, the dry plant material left behind after crops are harvested or trees are processed. The material is renewable and widely available, but difficult to break down. Converting it into fuels or other products often requires strong chemicals and high temperatures.

“The motivation was to find a cleaner way to process plant-based biomass,” Prof Bahadur said. “Traditional methods rely on harsh chemicals and high energy input. We wanted to assess alternatives that are safer and more sustainable.”

Deep eutectic solvents are typically made from affordable and low-toxic components: hydrogen bond donor and hydrogen bond acceptor. According to the study, they can weaken the tight structure of plant fibres, allowing useful parts to be separated more easily.

“These solvents help us reduce the intensity of the process,” he said. “If we can lower chemical use and energy demand, we move closer to responsible production.”

South African solution with global reach

The publication places the research on an international stage. Chemical Reviews is known for featuring work that shapes research directions in chemistry.

South Africa produces large volumes of agricultural and forestry residue each year. If processed more efficiently, that waste could support new industries and contribute to the energy supply. The study suggests that cleaner processing methods may determine whether plant waste becomes an environmental burden or an economic resource.

“For us, it confirms that research done in South Africa can contribute to global discussions on sustainable technology,” Prof Bahadur said.

Prof Indra Bahadur