2 CO₂ start-ups mature

Two companies built around turning carbon dioxide into minerals are advancing their business plans. Low-carbon cement start-up Solidia Technologies closed a $78 million funding round and named a new CEO, Bryan Kalbfleisch, who has 20 years’ experience in the concrete and building materials industries. Solidia says its process uses up to 40% less energy than conventional plants during cement production and consumes 240 kg of CO₂ per metric ton of cement during curing. Meanwhile, the start-up CarbonFree has signed a 1-year memorandum of understanding with the calcium chloride specialist Tetra Technologies. CaCl₂ is a feedstock for CarbonFree’s second-generation carbon mineralization technology, which produces calcium carbonate and hydrochloric acid. The firm already has a first-generation plant in San Antonio, Texas, that makes sodium bicarbonate and hydrochloric acid from cement plant flue gas. In addition to R&D and supply chain collaboration over the next year, the firms say they will work on the terms of a long-term partnership.