A process for drying oil, its application for the preparation of chloromethanes

This invention is a process for drying a mixture containing at least one hydrocarbon, hydrochloric acid and water, characterized in that placed in contact with a desiccant selected from i sulfates , metal chlorides or perchlorates or ii anhydrous phosphorus pentoxide until the drying agent has retained the major part of water. It is applied to the synthesis of chloromethanes to dry methyl chloride coming from the head of the separation column CH3 Cl / higher chloromethanes.