Phase Diagrams of LiCl-KCl-PbWO<sub>4</sub>, NaCl-KCl-PbWO<sub>4</sub>, KCl-Li<sub>2</sub>WO<sub>4</sub>-PbWO<sub>4 </sub>Three-Component Systems and Chemical Synthesis of Oxide Tungsten Bronzes of Alkali Metals and Lead
Study of the phase diagram of LiCl-KCl-PbWO4, NaCl-KCl-PbWO4, KCl-Li2WO4- PbWO4 three-component systems and chemical synthesis of oxide tungsten bronzes of alkali metals and lead in ionic salt melts. Methods. Differential thermal analysis (DTA) and X-ray phase analysis (XRD). Results. The coordinates of the triple eutectic points were determined: LiCl-KCl-PbWO4: Е: 320 оС, 57 % LiCl, 36 % KCl, 7 % PbWO4; NaCl-KCl-PbWO4: Е: 585 оС, 42 % NaCl, 40 % KCl, 18 % PbWO4; KCl-Li2WO4- PbWO4: Е: 510 оС, 43,5 % KCl, 46,5 % Li2WO4, 10 % PbWO4. It is shown that the calculated and experimental data on the coordinates of quaternary eutectics are in satisfactory agreement. Conclusions. The phase diagrams of the LiCl-KCl-PbWO4, NaCl-KCl-PbWO4, KCl-Li2WO4-PbWO4 three-component systems have been studied for the first time. It is shown that all of them are characterized by a simple triple eutectic point, which indicates the absence of chemical interaction between the components. The coordinates of ternary eutectics are revealed by the calculation-experimental method and DTA. It is shown that the calculated data on the coordinates of the triple invariant points are in satisfactory agreement with the experimental data. The chemical synthesis possibility of oxide tungsten bronzes for alkali metals and lead in ionic melts of the studied systems is shown