CO 2 sequestration may be an avenue to mitigate climate change. CO 2 sequestration by mineral carbonation can be achieved by the reaction of CO 2 with alkaline silicates. Here, we evaluate how alkaline silicate mineral-based CO 2 sequestration can be achieved using environmental biotechnological processes. Several biotechnological processes rely on the sequence of (i) an acid-producing reaction such as nitrification and anaerobic fermentation and (ii) an alkalinity-producing reaction such as denitrification and methanogenesis. Whereas the acid-producing reaction can be used to enhance the dissolution of, for example, alkaline calcium silicates, the subsequent alkalinity-producing step can precipitate CaCO 3 . We quantitatively evaluate the potential of these processes for CO 2 sequestration and propose that optimization of these processes could contribute to climate change mitigation strategies.