The Premier Reducing Agent for Textile Dyeing, Pulp Bleaching, and Industrial Applications
CAS No: 7775-14-6 |
Formula: Na₂S₂O₄ |
Grade: Industrial (88–90% Purity) |
Appearance: White crystalline powder
Sodium Hydrosulphite, also known as Sodium Dithionite or “Hydro,” is a powerful, water-soluble reducing agent
essential for a multitude of industrial processes. Our high-purity grade is a fine, white crystalline powder,
engineered for maximum performance and stability. It is renowned for its ability to decolorize, bleach, and reduce
chemical compounds, making it an indispensable tool in manufacturing and processing sectors.
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Key Properties & Specifications
Purity: 88%–90% Sodium Dithionite (Na₂S₂O₄)
Form: Free-flowing white powder for easy dissolution and handling
Key Function: Potent reducing and bleaching agent
Solubility: Soluble in water, creating a strong reducing solution
Industrial Applications & Uses
Sodium Hydrosulphite is a versatile workhorse chemical, critical to the following industries:
Textile Industry
The primary application of Sodium Hydrosulphite is in the textile sector, where it plays a crucial role in dyeing and finishing processes:
Vat Dyeing: It is the go-to reducing agent for vat and indigo dyes, converting insoluble dyes into their soluble “leuco” form, which allows them to penetrate and bond with fibers like cotton.
Color Stripping & Correction: It effectively removes or strips color from fabrics without damaging the fibers, making it ideal for correcting dyeing errors or creating patterns (discharge printing).
Bleaching & Brightening: It acts as a gentle bleaching agent for wool, silk, and nylon, improving the brightness and overall quality of the fabric.
Pulp and Paper Manufacturing
In the paper industry, Sodium Hydrosulphite is a key bleaching agent used to brighten wood pulp and recycled paper fibers.
It effectively removes lignin and other color-causing impurities, resulting in high-quality, bright white paper products.
It is also essential for the de-inking process in paper recycling.
Kaolin Clay Bleaching
Sodium Hydrosulphite is used to bleach kaolin clay, a mineral used in manufacturing everything from glossy paper and ceramics
to paint and rubber. The reduction process removes iron and other discoloring impurities to produce a purer, whiter clay.
Water Treatment
This chemical is used in water treatment applications to remove excess chlorine and for the reduction of chromate (Cr VI) to the less harmful Cr III.
It also helps stabilize certain polymers used in water purification processes.
Industrial & Commercial Cleaning
As a powerful reducing agent, it is the active ingredient in many commercial rust stain removers, effectively dissolving iron oxides
from various surfaces. It is also used in general industrial cleaning to decolorize and remove stubborn stains.
Other Important Uses
Leather Industry: Used in the bleaching and processing of leather hides.
Photography: It is a component in some developing solutions.
Food Additive: Used in some regions as a preservative and bleaching agent for products like dried fruits, sugar, and candy, where it prevents oxidation and discoloration.
Hair Care: Can be found in some hair treatment products as an antioxidant or for waving/straightening processes.
Advantages of Sodium Hydrosulphite
Powerful Reduction: Highly effective for vat dyeing and color stripping where other agents fail.
Cost-Effective: An economical choice for large-scale industrial bleaching and dyeing operations.
Versatile: Can be used on a wide range of materials, including natural and synthetic fibers, paper pulp, and minerals.
Gentle Bleaching: Offers a less aggressive alternative to chlorine-based bleaches for delicate materials like wool and silk.
Safety & Handling
Sodium Hydrosulphite is sensitive to moisture and air and must be stored in a tightly sealed container in a cool, dry, well-ventilated area.
Avoid contact with acids and oxidizing agents, as this can cause a dangerous chemical reaction.
Always use appropriate PPE, including gloves and safety glasses, during handling.
Consult the Safety Data Sheet (SDS) for comprehensive safety and disposal information.
Safety Reminder: Moisture/air sensitive. Store sealed in a cool, dry, ventilated place. Keep away from acids and oxidizers. Use PPE. Refer to SDS.
Request a Quote for Bulk Sodium Hydrosulphite
For a reliable supply of high-purity Sodium Hydrosulphite for your industrial needs, contact Dharma Hydrocolloid.
We offer competitive pricing and flexible packaging solutions to support your business.