Biomineralisation Cement

Portland cement production is responsible for approximately 8 percent of global CO₂ emissions — more than aviation and shipping combined. The problem is thermodynamic: limestone (CaCO₃) must be heated to 1450°C to decompose it into lime (CaO), releasing the CO₂ that was locked in the rock. That CO₂ is then cast into the atmosphere rather than into the concrete itself. Every tonne of cement clinker produced releases roughly 0.8 tonnes of CO₂, most of it from the chemical decomposition reaction rather than fuel combustion.

Corals and molluscs make calcium carbonate at ambient temperature by doing the thermodynamic process in reverse: they extract dissolved calcium and bicarbonate ions from seawater and use organic matrix proteins to nucleate and organise crystal growth. The CO₂ is fixed rather than released, and the resulting material is often stronger and tougher than geologically compressed limestone. The entire process runs at body temperature with no kiln.

Intropic Materials is developing a microbial cement that mimics biomineralisation. Engineered bacteria are applied to aggregate or injected into sub-surface formations; they catalyse the precipitation of calcium carbonate from dissolved minerals, binding particles together at ambient temperature. Unlike existing microbially induced calcite precipitation (MICP) technology, Intropic's platform controls crystal morphology through secreted organic matrices — replicating the shell-forming mechanism of molluscs to produce denser, stronger, and more predictable mineral bonds.

The carbon arithmetic is structurally reversed: rather than releasing CO₂ from limestone, Intropic's process draws dissolved inorganic carbon from water or soil and locks it into solid mineral. In principle, every tonne of bio-cement produced is carbon-negative — a complete inversion of the conventional cement life-cycle. Pilot projects are targeting ground stabilisation and road-base applications before moving to structural concrete markets.