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Novamem makes pure water available to all

An interview with Christoph Kellenberger, former Swiss researcher and current CEO of Novamem, a polymer membrane manufacturer.
Novamem makes pure water available to all
Novamem makes pure water available to all

Novamem is a fairly recent company. How did you come up with the idea of working on filtration membranes?

Novamem is a company with close ties to the Zurich Ecole polytechnique fédérale (ETH). We were still PhD students in Sciences and Chemistry when Michael Loepfe and I decided to set up this company in 2013. In the beginning, we focused exclusively on the membranes that we were developing and offering to industry and researchers. We have recently begun investigating more comprehensive point-of-use filtration systems for the general public that we market under the DrinkPure brand.

What are the specificities of your membranes?

The membranes that we develop are extremely hydrophilic and asymmetrical. We call them asymmetrical because they are made up of different layers in varying thickness and porosity. That being said, the most important feature in this type of membrane is the thickness of the first layer: the thinner it is, the higher the flow. It is in this regard in particular that we provide considerable added value. We offer ranges of membranes using technologies ranging from ultra-filtration to micro-filtration. Most of the membranes available on the market have pores measuring around 0.2 microns (one micron is a millionth of a metre). This size does not capture bacteria such as legionella and prevent them from passing through the sieve. Our pores measure between 0.05 and 0.15 microns, and are able to block almost all known bacteria as a result!

 

Novamem’s polymer membranes are some of the few with pores measuring between 0.05 and 0.15 microns, enabling them to block the bacterium responsible for legionellosis, for instance.

Is this their only advantage over your competitors’ membranes?

No, the nanoperforation technique used is another, and not the least. We have developed a process enabling us to distribute the pores across the surface of the membrane in a specific pattern. In fact, this is one of our manufacturing secrets and one of the reasons for our membranes’ high performance. The pores are small enough to capture impurities and are judiciously placed in order to offer a high flow rate. This exclusive distribution also explains their tendency not to get clogged. This is an additional boon for our customers, as the fact that the membranes do not clog up as fast provides them with a longer life.

 

The distribution of the pores across the surface of the polymer membrane required many hours of research in order to offer a higher flow rate than that offered by most other membranes available on the market.

Who are your membranes intended for?

We are focusing mainly on point-of-use filtration solutions. This means that we are looking first and foremost to bring the purest possible water to those who need it. This can mean individuals or industry, such as the pharmaceutical industry or researchers in the fields of chemistry or life sciences looking for pure water. It is a world with which we are familiar, as we started out there.

 

Novamem is able to imbue its membranes with the properties of the carefully-selected polymers: PES, PVDF and even the famous PEEK are used in their membranes.

Which polymers do you use?

We use several; it all depend on the end use. Without a doubt, the most used is hydrophilised polyethersulfone (PES), a high-performance medical-class polymer which is neutral and thus compatible with food and therefore water. It does not contain any phthalates, bisphenols or peroxides. Polyvinylidene fluoride (PVDF) is also largely used in our membranes, in particular where separating molecules is required.

 For instance, this polymer is used by a laboratory that was looking at isolating proteins present in a liquid. In that case, the membranes were not used to purify the water but rather to sift a liquid in order to only keep the elements useful to the research. Finally, some of the membranes are made of PEEK, as mentioned earlier.

You sell DrinkPure Home, a highly innovative product intended for the general public. Can you tell us more about it?
 

DrinkPure Home is an individual filtration system that fits onto any type of faucet. We are quite proud of it as it is a revolutionary water purification system. It is the only filter available on the market which can be fitted to a standard faucet and eliminates pathogens and pesticides. DrinkPure Home also reduces undesirable smells and tastes due to chlorine, for instance. We believe in our product, as it saves a lot of money. The filter only needs to be replaced every 500 litres. We drew up a comparison: for a standard family of four consuming bottled water every day, the DrinkPure Home will help them to save 850 Euros per year. That’s quite a bit!

 

Novamem’s polymer membranes have recently been used in the DrinkPure Home, a particularly innovative household water filtration device.

How does the DrinkPure Home work?
 

It is a multi-layered filtration system. The first layer is a fairly traditional filter that blocks a large proportion of impurities and bacteria. This layer also ensures the non-proliferation of bacteria when the filter is not in use. The second layer is also fairly traditional; it is made of activated carbon which eliminates undesirable smells and tastes. The final layer is the polymer membrane which is the subject of a patent relating mainly to its manufacturing process. The type of polymer is not the most crucial point; the real specificity is the number and size of the pores that block the remaining impurities and offer a flow rate comparable to that of an unfiltered faucet. All I can say is that it is a single membrane comprising three billion pores! We designed it when we were still scientists at the ETH. Novamem is currently the only company to produce patented membranes. This is no coincidence as we spent many years as researchers there before starting up our own company.

More information: https://novamem.com/

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