Carbon capture and storage in low-carbon concrete using products derived from olivine.

A novel process is reported that produces amorphous silica and nesquehonite (MgCO3 ·3H2 O) from the magnesium silicate mineral olivine ((Mg, Fe)2 ·SiO4 ). The amorphous silica forms a supplementary cementitious material for use in concrete. The formation of nesquehonite sequesters carbon making the overall process carbon negative. Nesquehonite can also be used to form low-carbon construction products such as bricks, blocks and boards. This article reports on key process optimization studies. The potential for amorphous precipitated silica derived from olivine to produce carbon-negative concrete is discussed.