Potassium Bisulfite
Potassium Bisulfite Supplier
Potassium Bisulfite (KHSO₃) is a potent reducing agent, antioxidant, and preservative valued for its ability to prevent oxidation and microbial spoilage across food, beverage, water treatment, and industrial applications. Where potassium is preferred over sodium — including in winemaking, specialty agriculture, and certain food formulations — potassium bisulfite offers a distinct advantage. With more than 75 years of experience as a pioneering innovator, Alexander Chemical supplies top-quality Potassium Bisulfite in liquid and solid forms, backed by expert technical guidance and reliable bulk delivery services. Safety and compliance are our top priorities.
Key Characteristics of Potassium Bisulfite
Chemical Properties
- Potassium Bisulfite Formula: KHSO₃
- Appearance: Clear to pale yellow aqueous solution (typically 35–40%) or white crystalline powder
- Odor: Faint sulfur dioxide (SO₂) odor
- Solubility: Highly soluble in water
- pH (solution): Acidic (pH 3–5)
- Related Compound: Closely related to potassium metabisulfite (K₂S₂O₅), which converts to bisulfite in water
Storage & Handling Requirements
- Store in cool, sealed, ventilated areas in HDPE or stainless steel containers
- Keep away from strong oxidizers, acids, and sources of heat
- Protect from air exposure — oxidizes to sulfate over time
Potassium Bisulfite is a hazardous material. Releases toxic sulfur dioxide gas (SO₂) when exposed to acids or heated. Can react vigorously with strong oxidizers. Sulfite sensitivity may affect individuals with certain medical conditions. Mishandling can lead to serious safety and environmental risks. Always rely on certified professionals for storage, handling, and transportation.
What are the Uses of Potassium Bisulfite?
Potassium Bisulfite is a highly effective and broadly applicable reducing agent and preservative, relied upon in industries where antioxidant protection, microbial control, or dechlorination is required.
Water Treatment & Dechlorination
Potassium bisulfite is used as a dechlorination agent in water and wastewater treatment, neutralizing residual chlorine in treated effluent prior to discharge or reuse. It reacts rapidly with free chlorine and chloramines, providing reliable residual removal with minimal impact on pH.
Wine & Beverage Preservation
Potassium bisulfite is one of the most widely used preservatives in winemaking and beverage production. It releases sulfur dioxide (SO₂) in solution, which inhibits oxidation, suppresses wild yeast and bacteria, and extends shelf life. It is approved as food additive E228 and is the primary source of ‘contains sulfites’ labeling on wine products.
Food Preservation & Processing
In the food industry, potassium bisulfite is used as an antioxidant and preservative to prevent enzymatic browning in cut fruits and vegetables, preserve color and freshness in dried fruits, and maintain the quality of fruit juices, seafood, and other perishable products.
Photography & Industrial Processing
Potassium bisulfite is used in photographic developing processes as a preservative and restrainer, preventing oxidation of developer solutions. It also finds application in textile processing and as a reducing agent in various industrial chemical processes.
Other Industrial Applications
- Specialty fertilizers providing potassium and sulfur nutrition
- Pulp and paper bleaching
Bulk Potassium Bisulfite Delivery & Support Services
The professionals at Alexander Chemical bring decades of experience and expertise to managing Potassium Bisulfite with precision and care. We supply and deliver to municipal utilities, industrial facilities, and specialty operations across the country.
What We Offer
- Supplying and delivering Potassium Bisulfite in bulk tankers, totes, or drums tailored to your specific requirements
- On-site technical support for optimal dosing and application
- Regulatory compliance guidance and safety training
- Regular tank inspections and maintenance recommendations
A Brief History of Potassium Bisulfite
Sulfite chemistry has its roots in the early 19th century, when the preservative and bleaching properties of sulfur dioxide were recognized and harnessed in food preservation and textile processing. The use of sulfites in wine — one of the oldest food preservation traditions — dates back to ancient Rome, where burning sulfur in wine vessels was a common practice to prevent spoilage. Potassium-based sulfites gained favor over sodium equivalents in winemaking and food applications because potassium does not contribute to sodium-related dietary concerns and provides a secondary nutritional benefit in agricultural uses. Modern winemaking codified the use of potassium bisulfite and metabisulfite as standard preservation tools in the 19th and 20th centuries. Today, potassium bisulfite remains a cornerstone of the global wine and beverage industry.
Potassium Bisulfite Facts
- The Wine Preservative: The ‘contains sulfites’ warning on wine labels exists because of bisulfite compounds like potassium bisulfite — which protect wine from oxidation and bacterial spoilage, keeping it fresh from cellar to glass.
- Dried Fruit’s Best Friend: The vivid orange color of commercially dried apricots isn’t natural — it’s preserved by potassium bisulfite, which prevents enzymatic browning and keeps dried fruits looking and tasting fresh.
- Ancient Sulfur Tradition: Romans burned sulfur in wine amphorae before sealing them — an early form of the same sulfur dioxide chemistry that potassium bisulfite delivers in modern winemaking, thousands of years later.
- Dual Nutrient Benefit: In agricultural applications, potassium bisulfite provides both potassium and sulfur — two essential plant nutrients — making it a functional specialty fertilizer component as well as a preservative.
- Potassium Over Sodium: Unlike sodium bisulfite, potassium bisulfite is preferred in applications where sodium intake is a concern — including wine, food products, and agricultural formulations where potassium nutrition is beneficial.
Frequently Asked Questions about KHSO₃
What is potassium bisulfite?
Potassium bisulfite (KHSO₃) is an inorganic salt that functions as a reducing agent, antioxidant, and preservative. It is commonly supplied as an aqueous solution (35–40% concentration) or as a crystalline powder, and is closely related to potassium metabisulfite (K₂S₂O₅), which converts to bisulfite in water.
What is potassium bisulfite used for?
Potassium bisulfite is widely used as a preservative and antioxidant in winemaking and food processing, as a dechlorination agent in water treatment, in photographic processing, and in specialty agricultural and industrial applications.
What is the difference between potassium bisulfite and potassium metabisulfite?
Potassium bisulfite (KHSO₃) is typically supplied as an aqueous solution, while potassium metabisulfite (K₂S₂O₅) is more commonly supplied as a dry crystalline powder. In water, metabisulfite rapidly converts to bisulfite and releases SO₂ — the active preservative agent. The two are functionally similar in most applications, with minor dosing adjustments for molecular weight differences.
Is potassium bisulfite food safe?
Yes. Potassium bisulfite is approved as a food additive (E228) in many jurisdictions and is widely used in winemaking and food preservation. Individuals with sulfite sensitivity or asthma may be sensitive to sulfite-containing products, which is why ‘contains sulfites’ labeling is required on wine and certain foods.
How is phosphoric acid delivered?
Alexander Chemical delivers potassium bisulfite via bulk tankers, intermediate bulk containers (totes), and drums based on your volume and site requirements. All deliveries are handled through Circle Transport, our dedicated logistics partner.
How should potassium bisulfite be stored?
Potassium bisulfite should be stored in cool, sealed, ventilated HDPE or stainless steel containers, away from strong oxidizers, acids, and heat. Solutions oxidize when exposed to air — containers should be kept sealed. Alexander Chemical provides tank inspection and maintenance support as part of our delivery and compliance services.
What industries use potassium bisulfite?
Potassium bisulfite is used in wine and beverage production, food processing and preservation, municipal water and wastewater treatment, photographic processing, textile processing, and specialty agriculture.
Where to buy potassium bisulfite in bulk?
Alexander Chemical supplies bulk potassium bisulfite with nationwide delivery. Contact our team to discuss your volume requirements, delivery schedule, and pricing.