The invention discloses a method for preparing and purifying cuprous
halide. The method comprises the following steps of: placing
copper halide in a reaction vessel, adding a glycol
solvent into the vessel, and keeping the constant temperature of between 130 and 180 DEG C for 24 to 48 hours to produce white cuprous
halide grains; and purifying the cuprous halide by a special purifying device; placing the cuprous halide serving as raw materials on the bottom of the purifying device; adding the glycol
solvent and a small amount of corresponding alkali halate into the vessel to make the vessel achieve about 90 percent of the degree of filling, and sealing the opening of the vessel by a plug or a cover which is provided with a pore; heating the vessel, keeping the temperature of a lower
clapboard on the bottom of the vessel at about 170 DEG C, and keeping the temperature of an upper
clapboard on the top of the vessel at about 150 DEG C; and depositing the purified cuprous halide on the surfaces of the clapboards, and washing and
drying the cuprous halide deposited on the surface of the upper
clapboard to obtain analytically pure cuprous halide. The method has the characteristics of simple equipment and method for synthesis and purification, mild condition, and
environmental protection; and the obtained cuprous halide has complete crystalline form, large grain size, high purity, and strong
oxidation resistance.