The effect of slag on the properties of magnesium potassium phosphate cement

- The byproduct B-MgO is used to formulate MKPC.
- The effects of slag on the properties of the MKPC system are studied.
- The addition of slag can improve the water resistance and seawater resistance of MKPC.
- The hydration products of MKPC are analyzed by XRD using the Rietveld method and SEM.

Magnesium potassium phosphate cement (MKPC) incorporated with slag was prepared from the byproduct boron-containing magnesium oxide (B-MgO) from the production of Li2CO3 from salt lakes. The influence of the slag content on the setting time, compressive strength, water resistance and seawater corrosion resistance of MKPC was investigated. The composition and microstructure of MKPC were also studied in detail. The results demonstrate that the setting time of MKPC increases with increasing slag content. The compressive strength at 3 h and 28 d of MKPC specimens with 20 wt% slag can reach approximately 35 MPa and 60 MPa, respectively. Moreover, slag significantly improves the water resistance and the seawater corrosion resistance of MKPC. The properties of MKPC incorporated with 20 wt% slag indicated that it met the requirements for rapid repairing materials.