**5. Conclusion**

The formation of MOC from natural brines was carried out in this study using experimental design. The results showed that there is an agreement between the experimental values and those calculated from the model developed which confirms its validity. The optimal conditions are MgCl2 .6H2 O/MgO (X1): 2.22, mixing time (X2): 5 min and stirring speed (X3): 1125 rpm. The responses are compressive strength = 76.40 MPa and setting time = 41 min. The interpretation of results found by DRX, IR, SEM and TG-DTA confirms the presence of phase 5 which is responsible for the good compressive strength of magnesium oxychloride cement.

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