PhD plays key role in feasibility of advanced biorefinery

Arjan Smit is a true inventor, holding five patents in biorefinery technology. He has been working at TNO for fifteen years, and in 2019, he initiated a collaboration with Utrecht University professor Pieter Bruijnincx to pursue a PhD and advance his work further. Their joint research now plays a crucial role in the feasibility of an advanced biorefinery at a demo scale. Smit defended his PhD on November 4.

Biorefineries are essential to developing a sustainable, bio-based economy. These facilities convert various types of biomass - such as agricultural and pruning residues, roadside grass, reeds, and even nutshells - into valuable building blocks for products like construction and packaging materials, coatings, bioplastics, and biofuels. While biorefineries have the potential to replace fossil fuel refineries, they are often not yet competitive, partly due to high processing costs.

Significant breakthroughs

During his PhD research and in the years leading up to it, Smit, along with a team from TNO, made significant breakthroughs to enhance the competitiveness and sustainability of biorefineries. By refining the Organosolv separation process, they discovered a cost-effective way to isolate high-quality green building blocks - such as cellulose, sugars, and lignin - from biomass.

Another key finding was the flexibility of the process to extract these compounds from a wide variety of biomass residues, further improving the feasibility and sustainability of biorefinery plants. “We can now convert eighty to ninety-five percent of biomass into high-quality green building blocks,” Smit explains. “The new process performs exceptionally well in terms of product yield, cost-effectiveness, and sustainability - something researchers haven’t achieved before.”

An advanced demo-scale biorefinery like this is a unique development

Worthless goo

Pieter Bruijnincx supervised Smit throughout his PhD research. Bruijnincx is a professor of Sustainable Chemistry & Catalysis, and an expert in biomass processing, particularly in lignin extraction and characterization. According to Smit, the collaboration with Bruijnincx and Utrecht University was pivotal in developing the process to isolate high-quality lignin. Lignin, a naturally abundant compound in plants, serves as a versatile base for various applications, including insulation foam, coatings, and adhesives for the construction industry. However, lignin’s chemical complexity makes it highly susceptible to degradation under overly harsh processing conditions. “A little too much energy, and you end up with worthless goo”, Smit explains.

Mini factory

Thanks in part to Smit’s research, TNO - working under the Biorizon Shared Research Centre and in collaboration with Dutch and European partners - is now developing a demonstration-scale biorefinery. This smaller-scale plant, with a capacity to process up to one million kilos of biomass per year, will convert various types of biomass into high-value building blocks, including premium-grade lignin. “An advanced demo-scale biorefinery like this is a unique development,” says Smit, who is coordinating the market rollout from TNO.

The plant is specifically intended to supply green building materials for the construction sector. “This is a deliberate choice, as we have major ambitions for bio-based building in the Netherlands,” Smit explains. “However, the technology is versatile enough for applications ranging from electronics to medicine.”