Abstract: A process for cleaning vessels containing liquid sulfur dichloride is disclosed. The sulfur dichloride is first removed from the vessel leaving a heel (residue) of liquid and solid material on the bottom of the vessel. The remaining liquid is vaporized by heating the vessel, and the vapors are removed by vacuum and purging, and neutralized by reaction with a basic solution. The vessel is purged with a dry inert gas during heating to prevent exothermic reactions and the formation of toxic reaction products, and to assist in removal of vapors from the vessel. The solid residue remaining in the vessel is then removed from both the bottom and wall portions. In a preferred aspect, the present invention is particularly applicable to cleaning railroad tank cars which are used to transport sulfur dichloride.

Abstract: Substantially all the liquid sulfur dichloride in a vessel is removed from the vessel leaving a heel (residue) of liquid and solid material on the bottom of the vessel. The remaining liquid is vaporized by heating the vessel, and the vapors are removed by vacuum and purging. The vessel is purged with an inert gas during heating to prevent exothermic reactions and the formation of toxic reaction products, and to assist in removal of vapors from the vessel. The removed liquid and vapors are neutralized by reaction with sodium hydroxide. The solid residue remaining in the vessel is then removed from both the bottom and wall portions.