Sodium Sulfite: Sodium sulfite is primarily used in the pulp and paper industry. It is used in water treatment as an oxygen scavenger agent; in the photographic industry to protect developer solutions from oxidation and (as hypo clear solution) to wash fixer from film and photo-paper emulsions; in the textile industry as a bleaching, desulfurizing and dechlorinating agent and in the leather trade for the sulfitization of tanning extracts. It is used in the purification of TNT for military use; used in chemical manufacturing as a sulfonation and sulfomethylation agent; used in the production of sodium thiosulfate. It is also used in some other applications, including froth flotation of ores, oil recovery, food preservatives, making dyes, etc.