Sodium dithionite solution stabilization

Abstract

Abstract Sodium dithionite in solution is widely used in bleaching and vat dyeing of textiles. Unfortunately, however, losses occur not only through decomposition during dissolving of the salt in question, but also during storage of the solution. To avoid decomposition of such solutions, the presence of sulfite ion is introduced by sodium sulfite, or a comparable variant compound preferably with a pH adjustment under either aerobic or anaerobic conditions. The effect hereof in protecting the sodium dithionite against aerobic decomposition is at 7 percent to 45 percent of the decomposition rate for unprotected systems. With air exclusion, the rate in the protected system is at 2 percent to 71 percent that for the unprotected system. As indicated, mixtures of sodium sulfite or sodium bicarbonate with sodium bisulfite (anhydrous) have likewise been found effective as a stabilizing media for the sodium dithionite solution, all by virtue of the sulfite ion concentration increase therein.

Inventors

• 👤 M Kise
• 👤 L Ellis

Bibliographic Details