Haris Kadrispahic

Haris Kadrispahic did not set out to spend his life in water. He was born in Bosnia, moved to Denmark at the age of 13, and trained first as an engineer at the University of Southern Denmark before adding a master's at Copenhagen Business School, which is an unusual combination he likes to point out himself, because it means he reads a balance sheet and a furnace temperature with roughly equal comfort. He wanted to work for a government agency, landed in a Danish environmental agency instead, and through it met the people who would pull him into water treatment. His first boss at LiqTech told him not to worry about the ceramics, that they would teach him all of that, and that what they actually needed was someone to keep everything organised and keep innovating. He took that literally for the better part of two decades.

Haris Kadrispahic became Head of Innovation at LiqTech, a Danish company that is one of the few in the world making membranes out of silicon carbide, which is the technical name for the abrasive grit you find on sandpaper and one of the hardest materials humans know how to make. A membrane is just a filter with pores measured in nanometres (millionths of a millimetre), and the usual ones are made of polymer, which is to say plastic, because plastic is cheap and easy to mass-produce. The catch is that plastic membranes give up in the nasty streams: very high or low pH, thick viscous liquids, oily water, the kind of conditions you meet in oil, mining and power plants. As Haris puts it, ceramic is for the industries where you need your membrane to withstand everything you throw at it, and that is exactly the corner of the market LiqTech went after.

Haris Kadrispahic's defining piece of work at LiqTech came out of a problem the company stumbled into. Around 2015 it joined a project to help the food and beverage industry cut its fresh-water intake by a quarter, and quickly discovered that its silicon carbide membrane, brilliant in heavy industry, could not hit the fine, precisely-controlled pore sizes that delicate food streams needed, because silicon carbide is, in his words, notoriously difficult to control. So his team went back to the drawing board and built a hybrid membrane around zirconia oxide, a food-grade ceramic that regulators already trust, engineered to sit reliably below 100 nanometres and to be dialled in anywhere between 40 and 100 nanometres on demand. That opened doors that had been shut to the company, from dairy to protein concentration, without giving up the chemical and mechanical toughness that made ceramic worth the trouble in the first place.

Haris Kadrispahic is candid about why ceramic membranes remain a niche rather than the default, and it is not about performance. Polymer membranes won the volume early because they are cheaper and easier to produce, and ceramics have been playing catch-up ever since, because the economics hinge on the furnace: the more membranes you fire at once, the lower the cost of each, so you need a steady inflow of orders just to keep prices competitive against an incumbent that already has scale. He is optimistic anyway, and pointedly optimistic about the whole ceramic category rather than only his own corner of it, which is a tell about how he thinks. What gets him out of bed, he says, is the environment, and a part of his job he clearly relishes is sitting with European and Danish legislators to explain what the technology can actually deliver, because regulators only legislate for what is achievable, and that feedback loop between what is possible and what becomes law is where he feels he can move things.

Haris Kadrispahic left LiqTech in 2022 to start B4C, his own independent ceramic-membrane R&D company based near Copenhagen, which carries the same thesis forward: that ceramic membranes deserve more of the water-filtration market than they currently hold, across food and beverage, textiles, mining and power. It is the natural next chapter for someone who described, back on the show in 2021, a vision of membranes that do more than sieve by size, membranes with an active catalytic layer that can target specific unwanted compounds rather than just block anything above a certain size, which he called the next step in membrane evolution. You can hear the full episode below, and it remains one of the more enjoyable explanations of why the hardest material on the shelf is quietly doing some of the most stubborn work in water technology.

“Don't you worry about ceramics. We'll teach you everything about ceramics. What we need you to do is to keep everything floating, to keep everything organized, and to keep innovating.”

That instruction, from his first boss, is more or less the job description he has kept ever since, first at LiqTech and now at B4C.