Abstract: The performance of magnesium potassium phosphate cement is closely related to the content of MgKPO4·6H2O (K-struvite). In this study, the relative content of K-struvite and MgO in magnesium phosphate cement was analyzed by the adiabatic method and Rietveld method based on X-ray diffraction, and the formula for converting relative content into absolute content was proposed. The dehydration temperature and absolute content of K-struvite were determined by thermogravimetric method, and the results were compared with the results obtained by adiabatic method and Rietveld method. The results obtained from the three methods were consistent. Adiabatic method and Rietveld method are simple and fast in the analysis of the relative content of K-struvite, but the required relative information is much more than that of thermogravimetric method when converting to absolute content, therefore the thermogravimetric method is more operational.
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