Utrecht chemistry researchers develop elegant trick for more efficient biomass conversion

Student project leads to patent and hot paper

Chemistry researchers at Utrecht University have found a much more efficient way of converting biomass into so-called bio-aromatics. Previously, these useful chemical building blocks could only be made out of sugars from wood via an inefficient detour, resulting in many unwanted by-products. Under supervision of Prof. Pieter Bruijnincx, Master’s student Bart Fölker developed a clever trick that no longer requires this detour: by linking two chemical reactions in a ‘tandem conversion’, the raw material is now converted more directly and efficiently into the desired end product. The results were published in the scientific journal Angewandte Chemie.

In his graduation project, Fölker and his supervisor Chris Lancefield studied the Diels-Alder reaction, an important step and a bottleneck in the conversion of such sugars into bio-aromatics.

“The semi-finished products that are readily made from wood sugars cannot be easily seduced to engage into a Diels-Alder reaction,” says lead researcher Prof. Pieter Bruijnincx. Not only are these products not very reactive, but if they do react at all, they often produce various undesirable by-products: in this case, three out of four reaction products were unwanted.

Yahtzee

In the newly found method, the one desired product is extracted from the reaction, after which the others are converted back into the raw material. This process is repeated until the entire raw material is converted into the desired product.

The method can be compared to a game of yahtzee with an unlimited number of turns. After each roll, you set aside the dice that show sixes – the desired end product – and roll the rest of the dice again. By repeating this often enough, you eventually end up with only sixes.

Patent and spin-off

In this project, the researchers collaborated with TNO, which was so enthusiastic about the outcome that they applied for a patent together with Utrecht University and are now working on further developing and upscaling this process. The patent, which has now been granted, is included in the technology portfolio of the recently established TNO spin-off Relement.

Biomass as a circular raw material

Although biomass is often referred to as an energy source, it is actually better suited as a renewable raw material for high-value material applications. Biomass can replace fossil raw materials in the production of plastics, paints and coatings, composites, lubricants and consumer care products, for instance. A major challenge in this process is finding efficient ways of converting biomass. Utrecht researchers have been working on this challenge for a number of years now in order to contribute to closing the carbon chain. This is also one of the spearheads of the Circular Economy hub.

Publication

Dynamic Trapping as a Selective Route to Renewable Phthalide from Biomass-Derived Furfuryl Alcohol
Christopher S. Lancefield*, Bart Fölker*, Razvan C. Cioc*, Katarina Stanciakova*, Rosa E. Bulo*, Martin Lutz, Marc Crockatt, Pieter C.A. Bruijnincx*
Angewandte Chemie, 3 September 2020, DOI 10,1002/anie.202009001

* researchers associated with Utrecht University