Process for producing anhydrous alkali metal hydrosulfites

摘要

A process for producing an anhydrous alkali metal hydrosulfite comprises contacting hydrate crystals of an alkali metal hydrosulfite with an alkaline aqueous solution of a dehydrating agent having a pH of at least about 7. The slurry formed is maintained at or above the transition temperature to covert the hydrate crystals to anhydrous crystals of the alkali metal hydrosulfite. The process permits the conversion of hydrate crystals to produce anhydrous crystals of alkali metal hydrosulfite without substantial dissolving or decomposition of the alkali metal hydrosulfite.