The invention relates to high-purity cesium
carbonate, the content of the cesium
carbonate is greater than or equal to 99.999% wt in terms of Cs2CO3, and the total content of impurities Li, Na, K, Rb, Ca, Mg, Al, Fe, SiO2 and heavy
metal (in terms of Pb) is less than or equal to 0.001% wt. The preparation method of the high-purity cesium
carbonate comprises the following steps: leaching pollucite serving as a
raw material with
sulfuric acid, crystallizing and recrystallizing a leaching solution to obtain high-purity cesium
alum, and adding at least one of cesium
chloride,
cesium sulfate and cesium
nitrate during recrystallization and
dissolution of cesium
vanadium; and removing aluminum, converting, purifying and removing impurities to obtain a high-purity cesium carbonate solution, evaporating, concentrating, carbonizing and crystallizing to obtain high-purity cesium
bicarbonate, and finally
drying and decomposing to obtain the high-purity cesium carbonate. Compared with a conventional method for preparing cesium carbonate by extracting cesium from pollucite and a conventional method for preparing high-purity cesium carbonate by extracting cesium from pollucite, the method has the advantages that the product purity is greatly improved, and particularly, the
impurity Rb of the same family is less than or equal to 0.0001% wt.