Earlier this year, BASF was forced to postpone the opening of a battery materials plant in Finland after a court ruled in favor of environmental groups that the company did not have an adequate plan for wastewater treatment.
As battery factories spring up around the world, wastewater issues have been a hindrance, but one startup claims the solution lies in recycling wastewater rather than disposing of it.
Wastewater from these factories contains high amounts of sodium sulfate, a by-product of sulfuric acid and caustic soda, two chemicals used in battery manufacturing, copper smelting and other industries.
“You can build an entire circular economy around these reagent chemicals,” Bilen Akuzum, co-founder and CTO of Aepnus Technology, told TechCrunch.
Aksum and co-founder Lucas Hackl didn't set out to create a small-scale circular economy business, but stumbled across it by chance while touring lithium mining operations in California and Nevada. The two chemists, friends since meeting in a dorm cafeteria, had been researching startup ideas.
“We were thinking about lithium extraction or something in the minerals space,” Aksum says. “Every time we talked to people in the industry, they were like, 'Actually, we have a solution for lithium extraction, but we have waste products from our operations and we don't really know what to do with them.'”
After returning from their trip, Aksum and Hackle refined their idea, eventually deciding to improve on existing technology to turn the waste into raw materials that could be used to run the facility.
The two founded Aepnus to modernize the century-old chlor-alkali process, which breaks down salts such as sodium sulfate into the acids and bases from which they originate.
The company uses an electrolyzer to break down the salt. Other companies do the same, but use expensive metals to speed up the reaction. “We don't use expensive catalysts in our electrolyzer,” Akzum says.
Aepnus is currently shipping half-scale models of its device to customers so they can test it at their own wastewater treatment plants. Each facility's wastewater can contain a variety of contaminants, some of which must be filtered beforehand. Once those are removed, the electrolyzer can get to work removing the sodium sulfate.
For customers, fully recycling their sodium sulfate waste should reduce disposal and material costs. It also saves companies in remote locations, like miners, money on transportation. “Instead of mining companies buying these chemicals and having to truck them in from very far away, they can regenerate that chemical on-site from the waste,” Akzum says.
The startup has more than 15 customers at various stages of development, from feasibility studies to testing pilot-scale devices. Aepnus recently raised an $8 million seed round to ship more pilot-scale electrolyzers and develop a commercial-scale version. The round was led by Clean Energy Ventures, with participation from Gravity Climate Fund, Impact Science Ventures, Lowercarbon Capital, Muus Climate Partners and Voyager Ventures.
If Epnus can commercially produce the electrolyzer, it would be a milestone for the U.S. “There are only a handful of companies in the world that have the expertise to build this kind of electrolyzer,” Aksum says. “Unfortunately, there is no company in the U.S. with that know-how.”