Researchers say new seawater-derived cement could decarbonise the concrete industry. 

Magnesium ions are abundant in seawater, and an international research team has found a way to convert these into a magnesium-based cement that soaks up carbon dioxide.

Researchers say the process can convert magnesium ions from seawater into magnesium hydroxides and further into magnesium-based cement that soaks up carbon dioxide.

In tests so far, the magnesium-based cement exhibited compressive strength comparable to that of Portland cement.

Although the process requires a similar amount of energy per ton as the manufacture of Portland cement and is currently unsuitable for use in conventional reinforced concrete, the overall process would consume rather than emit carbon dioxide if the electricity that powers the electrochemical processing step is derived from carbon-free sources. 

The compound could be readily adopted for small-scale use in footpaths, masonry and pavers. 

More details are accessible here.