Raw material and auxiliary material from the same waste stream in new Argentine research
Researchers from Argentina have used pruning waste to create the carrier material for a catalyst that breaks down plant fibers into usable chemical building blocks. With this, the raw material and the tool come from the same source for the first time: plant-based residue. The study was published on August 12 in the journal Waste and Biomass Valorization.
From plant fiber to usable building block
The research revolves around cellobiose, a sugar consisting of two linked glucose units. Chemists use this substance as a simplified imitation of cellulose, the tough material from which plant fibers are composed. Cellulose itself is difficult to work with in laboratory experiments; cellobiose behaves similarly but is easier to monitor.
In the process, two things happen simultaneously. First, the bond between the two sugars is broken, after which the released sugars are converted using hydrogen. The end product is, among other things, sorbitol. Many people know this substance as a sweetener in sugar-free chewing gum, but for the chemical industry, sorbitol is primarily of interest as an intermediate product. Isosorbide is made from sorbitol, a building block for plastics that currently still largely come from petroleum. Fellow professionals know the reaction as hydrolytic hydrogenation.
Two supports, one made of pruning wood
A catalyst typically consists of an active metal applied to a support material. That support material helps determine how well the metal is distributed and how the reaction proceeds.
The researchers created two carbon carriers in the laboratory and applied ruthenium to them. One carrier, designated as Cas, was synthesized entirely in the lab. The other, BCf, was formed by pyrolyzing lignocellulose from pruning waste, that is, heating it without oxygen. Both carriers contain acidic groups and also possess a hydrogenating function, allowing the two necessary steps to take place on the same material.
The materials have been investigated using a range of techniques, including electron microscopy, Boehm titration, infrared spectroscopy, thermal analysis, and nitrogen adsorption.
What the trials yielded
According to the summary, the supports themselves achieved a conversion of 90 percent of the cellobiose, with glucose as the main product. This indicates that the acidic groups on the carbon surface largely account for the first step. The precise conditions under which this measurement took place can only be found in the full publication, which is behind a paywall.
After 200 minutes at 150 degrees Celsius and 3 megapascals of hydrogen pressure, both ruthenium catalysts converted approximately 80 percent of the cellobiose. The system based on pruning waste worked faster. The researchers attribute this to a more favorable distribution of the metal over the surface.
The composition of the yield did differ, however. In the laboratory carrier, the hydrogenated compounds, cellobitol and sorbitol combined, accounted for 53 percent of the selectivity. In the carrier from pruning waste, this was 38 percent, while the products from the first reaction step actually had a greater influence there, at 47 percent. Moreover, glycerol was formed in the latter catalyst, accounting for 14 percent.
Opportunities and caveats
The appeal of this route lies in the simplicity of the starting material. Pruning waste from green space management is readily available, including in the Netherlands, and is currently primarily composted or incinerated for energy. If such a residual stream proves usable as catalyst material, an application is added that sits higher in the value pyramid than incineration.
There are significant trade-offs. Cellobiose is a model compound, whereas real plant fibers are much more complex and also contain lignin and hemicellulose that can interfere with the reaction. Moreover, ruthenium is a scarce and expensive precious metal, which makes scaling up economically difficult. The trials were conducted on a laboratory scale. Consequently, the research is not aimed at direct industrial application, but rather at how catalyst carriers from biomass compare to conventional materials.
The work was carried out by researchers from the Universidad Nacional del Noroeste de la Provincia de Buenos Aires, the CITNOBA research center in Pergamino, and CINDECA in La Plata, which is affiliated with the CONICET research council and the Universidad Nacional de La Plata. The paper was submitted in June 2025 and accepted in early August 2026.
Source: Chiosso, ME, Méndez, LJ, Navone, MA et al., “Use of Lignocellulosic Biomass Derived Carbon-Based Materials as Supports and Catalysts in the Valorization of Cellobiose”, Waste and Biomass Valorization , August 12, 2026
Photo: Denis MOREAU from Pixabay
