Production technology of high purity phosgene with low hydrogen chloride content

The invention relates to a production technology of high purity phosgene with low hydrogen chloride content. The production technology comprises the following operation steps: the mixed gas with rich phosgene, unreacted excessive carbon monoxide and other impurities enters at least one rectifying tower, the top of each rectifying tower is provided with a fractional condenser, the liquid phase is used for refluxing, most of hydrogen chloride is discharged from the top of the rectifying tower along with CO and high purity phosgene is obtained at the bottom of the rectifying tower; and the gas discharged from the top of the rectifying tower passes through at least one absorption tower to wash away and recycle phosgene. The production technology in the invention has simple process flow and low production cost and is convenient to operate; and the hydrogen chloride content of the obtained phosgene product is greatly reduced, the purity of phosgene is more than 99.90% and the obtained phosgene can be used for the p