The invention provides a
potassium chloroaluminate fused salt and a preparation method thereof, and the preparation method comprises the following steps: uniformly mixing dried AlCl3 and KCl raw materials, adding into a
crucible, and heating to melt the mixed raw materials in the
crucible to form an AlCl3-KAlCl4 mixed fused salt; the method comprises the following steps: adding a small amount of KCl into
molten salt for multiple times until no volatile matter is generated in a
crucible to form KAlCl4
molten salt, and carrying out hot
filtration on the pure KAlCl4
molten salt to obtain pure, transparent and
impurity-free
potassium chloroaluminate; wherein the AlCl3 in the raw materials needs to be appropriately excessive, so that after the raw materials form a melt, a small amount of free AlCl3 exists in the molten salt, and pure KAlCl4 is formed by adding a small amount of KCl for multiple times in the subsequent process to chemically combine the free AlCl3; in this way, it can be avoided that due to the fact that AlCl3 in molten salt is insufficient, free KCl is formed, the molten salt is large in
viscosity and poor in flowability, and free particles block pipelines and valves of equipment; the prepared fused salt is free of free KCl, precipitates and other impurities, low in
vapor pressure and good in fluidity, and can be used for fused salt rectification separation of the
zirconium-
hafnium chloride, the operation efficiency of a rectification
tower device is guaranteed, and secondary
pollution of the
zirconium-
hafnium chloride is avoided.