Sequestra is a Vienna-based climate-tech startup that in June 2026 secured Austrian federal grants from FFG and Austria Wirtschaftsservice to build what it calls the first laboratory dedicated to mineral CO2 storage. Its process accelerates natural mineralisation to capture up to 300 kg of CO2 per tonne of feedstock from biomass ash, incineration residue and steel slag — public grants doing the early-stage work private capital has been slow to back in carbon mineralisation.