Separation instead of destruction - why "gone" with PFAS does not automatically mean "dissolved"

Author: Dr Verena Stenert

Dr Verena Stenert has a doctorate in chemistry and has been working in the water purification industry for almost two decades. She has been working intensively on the removal of PFAS for over ten years and contributes her extensive expertise to a wide range of cleaning processes.

At Cornelsen Umwelttechnologie GmbH, she is responsible for managing research projects and carries out laboratory and technical centre tests on behalf of customers. A particular focus is on the innovative and patented PerfluorAd® process for PFAS removal, which she regularly presents at specialist events and customer presentations.

With a keen sense for technical developments and new analytical approaches, Dr Stenert is constantly working on further developing existing processes - because the challenges in the field of PFAS elimination are constantly growing.

Table of contents

In conversations about PFAS, sooner or later the same demand almost always crops up:
You simply have to destroy these substances. Preferably completely. As definitively as possible.
The idea behind it is understandable. Destruction sounds consistent, clear, almost reassuring. If something is problematic, it should disappear. In practice, however, this approach is rarely as clear-cut as it first appears.


PFAS are extremely stable substances. This is precisely what makes them problematic - and precisely what makes their handling technically challenging. Destruction processes intervene deeply in chemical or thermal processes. This can make sense, but it almost always has side effects: high energy consumption, complex system concepts and, above all, the question of what is actually created in the process. After all, destruction does not automatically mean that nothing is left over at the end. Often, new (sometimes much more problematic) residual materials or by-products are created, which in turn have to be treated, stored or disposed of. The original problem has then not disappeared, but merely shifted.

That is why we at the Cornelsen Group take a different, deliberately pragmatic approach: separation and controlled removal. The focus is on specifically separating PFAS from contaminated media - without chemically or thermally altering them. This means that no new substances or additional reaction products are created. The substance remains the same, but it is located where it can be controlled.


A key advantage of this approach is the significant reduction in waste volumes.
Instead of treating large volumes in an energy-intensive manner, the relevant material flow is initially concentrated and controlled. This reduces technical complexity, lowers risks and prevents the creation of new waste streams, which in turn cause problems. This approach is not an end in itself, nor is it an alternative to destruction. Destruction processes can be useful - but not as a reflexive standard solution. Only when it is clear which substances are actually present, in what quantities and in what context, can a well-founded decision be made as to whether and which further step is necessary.
Separation creates the basis for this.


It brings order to the system, makes material flows transparent and enables decisions to be made on the basis of real data rather than theoretical assumptions.

Or to put it another way: not everything that looks "gone" at the end has really disappeared.


Sometimes the less spectacular route is the more stable - and the more responsible one.