LAUSR

The solubility of (KH2PO4 + KCl + H3PO4) at 298.15 K and 308.15 K were determined, using isothermal solution saturation. The equilibrium phase solid was verified by X-ray diffraction (XRD). On the basis of the experimental data, the phase diagrams were plotted. The crystalline regions of KH2PO4 and KCl were determined. The phase equilibrium in different phosphoric acid concentrations are compared and discussed. This comparison further illustrates that the phosphoric acid concentration can influence the equilibrium besides temperatures. All results can offer a fundamental basis for crystallization and separation processes.