Written by Gianpaolo Rota, Application Specialist | August 12, 2024

Microwave sample preparation of asphalt samples laboratories for R&D and Q&C

Innovating for a Greener Tomorrow: The Future of Asphalt Research at TNO

Asphalt, a material most commonly associated with road surfaces, is at the center of a crucial sustainability challenge. At TNO Mobility & Built Environment, researchers are tackling this challenge head-on by developing methods to make asphalt more durable and recyclable.
Leading this research was Willem Suitela, a senior researcher with over three decades of experience.
TNO also performs elemental analysis in its Delft laboratory. “You can use the composition of the elements in the asphalt (such as lead, zinc, vanadium, iron, molybdenum, potassium, calcium) as a fingerprint”.
To perform this analysis accurately, it is essential that the sample be broken down into the smallest possible particles and completely digested with concentrated acid during sample preparation.

MICROWAVE DIGESTION TECHNIQUES AND PAIN POINTS

At TNO Mobility & Built Environment, the journey towards more sustainable infrastructure is being driven by innovations in material analysis, particularly in the realm of asphalt. Central to this progress is the ETHOS UP microwave digestion system, which has revolutionized how we approach the analysis of asphalt and other construction materials.
For over 30 years, Willem Suitela spearheaded research at TNO, focusing on making asphalt not only more durable but also recyclable. Traditional methods of sample preparation often fell short in achieving complete digestion of asphalt, a complex mixture of hydrocarbons. However, the introduction of the ETHOS UP system changed the game. This advanced microwave digestion technology, with its powerful 2 x 950 watt magnetrons, has enabled our researchers to achieve 100% digestion of asphalt samples, ensuring that our elemental analysis is both accurate and reliable.
Microwave digestion, while not necessarily faster, has proven to be significantly more effective than older methods. The ETHOS UP allows them to process multiple samples simultaneously, using minimal material while achieving complete digestion. This breakthrough has provided TNO with a robust tool for exploring the sustainability of asphalt, including how additives like fibers and polymers impact its durability and recyclability.

As Willem Suitela embarks on his well-deserved retirement, the mantle of this critical research passes to Marla Cambil, a talented chemist whose expertise in microwave digestion will be instrumental in pushing the boundaries of asphalt research further.

“A big advantage is that we use much less sample material than before and achieve 100% digestion for asphalt.”
- Marla Cambil, researcher at TNO Mobility & Built Environment

CONCLUSION

With the ETHOS UP system at the heart of its laboratory, TNO is well-equipped to continue leading the way in developing more sustainable construction materials. This is more than just research— it’s a step toward a greener future.