Berlinite substitution in the cement clinker

Incorporation of P2O5 in clinker minerals in laboratory samples of clinker with graded content of P2O5 were studied by means of electron microscopy. The most important outcome is that P2O5 enters partially the structure of clinker silicates together with Al2O3 via berlinite substitution (Al3++P5+↔2 Si4+). Therefore, experiments were also carried out with the pure components and the influence of P2O5 on clinker phase composition in the absence of one of the main clinker oxide (Fe2O3 and Al2O3) was examined. It was found out that raw mix without Fe2O3 eliminates to a certain level negative influence of P2O5 on alite formation. The work was completed with preparation of white cement with high content of P2O5 in clinker, which exhibited good technological properties.