From polymer technology to international research centres – Chemical engineering alum of the year Petri Lehmus

Petri Lehmus, Vice President of Research and Development at Neste Corporation, has been named the 2025 Alumnus of the Year by Aalto University’s School of Chemical Engineering. Lehmus is an experienced R&D leader with a career spanning polymer technology, renewable fuels, and sustainable circular systems.

Lehmus began his career at Borealis as a catalyst researcher at the turn of the millennium, eventually becoming Head of Catalyst Process Technology Research. In 2007, he had the opportunity to establish a world-class polymer technology research centre in Abu Dhabi — a nearly €100 million investment.

'The experience in the UAE was eye-opening for me. I had been quite Eurocentric before, but during those years I learned to see the world from a different perspective. There was a positively competitive atmosphere there. I realised there’s a tremendous hunger for growth, learning, and development around the world. In Europe, we sometimes stay too much in our comfort zone,' Lehmus reflects.

In 2011, Lehmus returned to Finland to take up the role of Vice President of Research and Development at Neste. Building the company’s renewable business has been a remarkable success story: today, Neste is the world’s largest producer of renewable diesel and sustainable aviation fuel.

'I’ve spent my entire career in research and development. I’ve been involved in many research centre projects — as a side result of the centre we established in Abu Dhabi, a smaller Application Centre was created in Shanghai, and now Neste also has a research centre in Singapore. These research centres have been milestones in my career, which has been both meaningful and inspiring work,' says Lehmus.

A third-generation chemical engineer

Lehmus began studying chemical engineering in 1991, majoring in polymer technology and minoring in technical chemistry. His studies also included courses in physical chemistry and industrial engineering. He completed his licentiate thesis in 1999 and his doctoral dissertation in 2001, finishing his dissertation while already working full time.

“Professors Jukka Seppälä and Outi Krause had a strong influence on the school at that time, particularly during my postgraduate studies. They both had industrial experience — including from Neste — and their practical, applied approach to research had a major impact on me,” Lehmus explains.

Lehmus is a third-generation chemical engineer — his father, grandfather, and grandmother all worked in the field, and both his brother and wife are also chemical engineers. While chemistry was highly valued in the family, it did not directly determine his choice of study.

“At first, I was deciding between chemistry and physics. In the late 1980s, the Nobel Prize in Physics was awarded to the developers of superconductors, which fascinated me. In the end, I chose chemistry — and my excellent chemistry teacher at the German School of Helsinki also influenced that decision,” Lehmus recalls.

Long-term cooperation with Aalto

Neste and Aalto University share a long tradition of collaboration. Their joint research portfolio is coordinated in regular meetings with professors of chemical engineering, where the progress of projects, the company’s needs, and Aalto’s strategic goals are reviewed.

Lehmus serves on the Industrial Support Group of the School of Chemical Engineering and on Aalto University’s Support Foundation as a member appointed by the Chemical Industry Federation of Finland. The group’s goal is to develop the school’s operations and ensure that research and education programmes meet the current and future needs of companies and society.

“Occasionally, I’ve had the opportunity to lecture at Aalto. For example, in this autumn’s Aalto Inventors course, I gave the opening lecture and shared Neste’s story with the participants. Previously, I’ve also given some individual lectures,” says Lehmus.

Many Aalto University graduates work at Neste, particularly in the fields of technology and business. According to Lehmus, Aalto is one of the most significant sources of talent for Neste.

A strong foundation in chemistry is the key to everything

According to Lehmus, a strong command of the fundamentals of chemistry is essential for chemical engineers. Although information is readily available and AI is a useful tool, without a solid foundation of basic knowledge there is nothing to build upon.

“In addition to a firm grasp of the basics, another important skill is the ability to absorb and critically evaluate information. The amount of information today is enormous, and it’s crucial to recognise what can be trusted. Using artificial intelligence and other tools to find information is valuable, but critical thinking remains essential,” says Lehmus.

A background in chemical engineering opens doors to a wide range of career paths in both business and research. There is a growing demand for experts who promote sustainable development, and chemical engineering offers the opportunity to create solutions — not just observe from the sidelines.

“Although many think that chemistry is the cause of many problems, I personally believe that chemistry can help solve the major challenges of our time. It’s a field where you can do meaningful and impactful work,” Lehmus concludes.