In the production of Portland cement about 1 ton of CO
2 is produced for every ton of cement.
Adding metakaolin to Portland cement will reduce the final amount of CO
2 developed in relation
to pure cementitious binders.
With the environmental concerns developed in recent years, more environmental friendly cements
are produced adding ground slag, fly ash or other minerals. These new cements react more slowly
than CEM I.
Metakaolin is so far the only product which will reduce the CO
2 output and accelerate the
setting
.