Product Overview

Potassium Metabisulphite 96% AR (CAS No. 16731-55-8) is a potassium sulphur(IV) reagent that generates bisulphite and related sulphite species upon dissolution. These species function as reducing agents and react readily with many oxidants, while atmospheric oxidation can gradually convert active S(IV) material toward sulphate. This redox responsiveness makes metabisulphite useful in conventional analytical reagent preparation and controlled reduction steps.

The AR grade is intended for wet-chemical reduction, quenching of compatible oxidants, preparation of sulphite/bisulphite reagents and analytical QC procedures.

Typical Applications

• Preparation of reducing reagent solutions for conventional wet chemistry.
• Quenching or removal of residual compatible oxidants during sample or reagent treatment.
• Preparation of bisulphite/sulphite solutions for analytical procedures.
• Laboratory dechlorination studies based on S(IV) reduction chemistry.
• Redox titration and method-development work involving sulphite chemistry.
• Protection of oxidation-sensitive analytical preparations where the method specifically permits metabisulphite.

Common Synonyms

• Potassium metabisulfite
• Potassium pyrosulphite
• Potassium pyrosulfite
• Dipotassium disulphite
• Dipotassium disulfite
• Pyrosulphurous acid dipotassium salt

Storage Conditions

Keep tightly closed and minimise exposure to air and moisture so that reducing capacity is not progressively lost through sulphur(IV) oxidation or other compositional changes. Avoid oxidising contamination and prepare analytical solutions in accordance with the applicable method when fresh reducing capacity is critical.