Production process for refined hydrogen iodide

摘要

A process for producing refined hydrogen iodide having organic components of 0.2 ppm by volume or less and water of 0.1 ppm by volume or less by contacting crude hydrogen iodide with a zeolite is disclosed. Crude hydrogen iodide is obtained by reducing iodine with a hydrogenated naphthalene, wherein all of the iodine is dissolved in advance in a portion of the hydrogenated naphthalene to prepare an iodine solution, and the reaction is carried out while adding continuously or intermittently the iodine solution to the balance of the hydrogenated naphthalene. The same operation may be repeated in succession using unreacted hydrogenated naphthalene and fresh iodide. The zeolite is contacted in advance with crude hydrogen iodide, the amount of which is at least +E,fra 1/3+EE (weight ratio) relative to the amount of the zeolite, to convert impurities of sulfur components contained in the zeolite to hydrogen sulfide, thereby removing the sulfur components. Further, an activated carbon may be combined with the zeolite at the rear stage thereof.