Our favorite sustainable engineering projects of 2025: reuse, bio-based materials, and circular chemistry

Every year, our team works on a diverse combination of sustainable engineering projects. In 2025, a few of our colleagues reflected on the initiatives that truly inspired them. From reusable glass systems to bio-based materials and chemical recycling, explore the sustainable engineering projects that inspired our team in 2025.

Reusable glass: PAKT

Adam’s favourite project of 2025 was PAKT, a company rethinking how we handle glass packaging.

PAKT is building a circular return system for glass, covering collection, sorting, washing, and returning reusable bottles and jars. Their mission is to make reuse the norm, not the exception.

In 2025, PAKT launched a universal crate and return system designed to simplify the logistics of returning glass. We helped them scale up their washing facility in Woerden, which is optimised for energy, water, and chemical efficiency and runs on green electricity. The system is not only environmental; it is designed to be financially viable, as reuse reduces both material and waste-management costs.

Adam explains:

“I enjoy that this project challenges long-standing habits across society. It’s rewarding to work on a solution that directly empowers consumers to reduce their environmental impact through the simple act of returning used glass.”

This project is as much a systems challenge as a technical one, and we are proud to support PAKT in making circular reuse work at scale.

Bio-based acrylic acid: Låkril Technologies

Gunay’s favourite project of 2025 was with Låkril Technologies, who develop bio-based acrylic acid from renewable feedstocks, such as sugars produced from corn or other biomass.

The goal is to create a lower-carbon, sustainable alternative to conventional fossil-based production. The bio-based acrylic acid is designed as a drop-in replacement, meaning existing industrial users in coatings, adhesives, and superabsorbents can transition without re-engineering their entire process.

We are supporting Låkril in designing a scaled-up processing plant with their proprietary technology at its heart, including analysis of the business case and key cost drivers for a target capacity of around 40,000 metric tonnes per year.

Gunay shares:

“I enjoy the challenge of selecting the right technology and simulating the process. It is exciting to see how lab-scale innovation can grow into a real, sustainable industrial process.”

Circular chemistry: BioBTX

Rocio’s favourite project of 2025 was our work with BioBTX, an ambitious and deeply circular chemistry project.

BioBTX has developed a recycling technology based on pyrolysis and catalytic conversion that takes waste plastics and converts them into benzene, toluene, and xylene (BTX). These aromatics are key building blocks for the chemical industry, used in products such as coatings, foams, PET, and batteries.

TransitionHERO is working together with BioBTX to design and develop an industrial-scale process plant, read more about the project here.

Rocio explains:

“I enjoy the challenge of working on a first-of-a-kind plant, where engineering and creativity have to come together to deliver a design solution. I also really enjoy working together with the BioBTX team, who are very passionate and knowledgeable.”

Looking ahead

These projects reflect the kind of work we enjoy most: scaling circular and bio-based technologies, designing first-of-a-kind plants, and supporting the transition to more sustainable industrial systems.

We look forward to continuing this work in the year ahead.