English
water treatment chemicals
Sodium hydrosulfite Featured Image
  • Sodium hydrosulfite
  • Sodium hydrosulfite
  • Sodium hydrosulfite

Sodium hydrosulfite

Sodium hydrosulfite is a versatile reducing agent used in indigo dyeing. It can also serve as a mild alternative to bleach for removing color from dyed fabrics and bleaching antique textiles.


  • Molecular Formula: Na₂S₂O₄
  • CAS Number : 7775-14-6
  • Molar Weight : 174.107 g/mol
  • Appearance: White to off-white granular powder
  • Odor : Odorless or faint sulfur odor (sulfur dioxide odor)
  • pH : (50 g/L, 20°C) 5.5–8.5
  • Melting Point : 52°C

    • Applications

    FAQs about Water Treatment Chemicals

    Product Tags

    Na₂S₂O₄​​​​​ ≥90% ≥88% ≥85% ≥85%
    iron ≤20ppm ≤20ppm ≤20ppm ≤20ppm
    Zn
    		 ≤1ppm ≤1ppm ≤1ppm ≤1ppm
    Other heavy metals (calculated as lead)
    		 ≤1ppm ≤1ppm ≤1ppm ≤1ppm
    water-insoluble substance ≤0.05% ≤0.05% ≤0.05% ≤0.05%

    Properties

    Sodium hydrosulfite has unique chemical properties. It is extremely unstable in aqueous solution and readily decomposes into sodium sulfate, sodium sulfide, and sulfur dioxide. This compound has a melting point of 300°C and a boiling point of 1390°C, and is relatively stable under dry, low-temperature conditions. However, it is highly sensitive to moisture and air, which accelerate its decomposition.

    Applications

    • Textile Industry: It can be used as a reducing agent in the dyeing process, allowing dye molecules to penetrate the fabric more effectively. It also serves as a bleaching agent for cotton and silk, enhancing the brightness and transparency of textiles.

    • Paper Industry: Sodium bisulfite is the preferred bleaching agent for mechanical pulp, thermomechanical pulp, and deinked pulp, significantly improving the whiteness and quality of paper products.

    • Food Industry: As a food additive, it serves as a bleaching agent and antioxidant for candied fruits, dried vegetables, noodles, and grapes. It helps preserve food color and extend shelf life.

    • Environmental Engineering: In wastewater treatment, sodium metabisulfite reduces harmful substances, contributing to the discharge of cleaner, safer water.

    • Chemical Industry: It acts as a reducing agent in the synthesis of thiourea and its sulfides, playing a crucial role in various chemical reactions.

    Packaging

    Packaged in iron drums or plastic bags, with net weights ranging from 15 to 200 kg. Available in 20/50 kg drums and 250 g double-sealed plastic zipper bags.

    Sodium Hydrosulfite详情图1
    Sodium Hydrosulfite详情图2

    Storage

    Store in a dry, cool, well-ventilated area at temperatures between +5°C and +30°C. To prevent chemical reactions, avoid contact with strong acids, oxidizing agents, water, and moisture. When handling the powder, wear gloves, a dust mask, and safety goggles. Keep this product out of reach of children and pets.

    Transportation

    As this product is sensitive to moisture and air, which may lead to the release of sulfur dioxide (SO₂), appropriate safety measures should be taken during transportation.

    Synonyms

    Sodium Dithionite

    Insurance Powde

    Dithionous acid

    Disodium salt

    Blankit

    Blankit IN

    Burmol

  • Previous:
  • Next:

    • How do I choose the right chemicals for my application?

    You can tell us your application scenario, such as pool type, industrial wastewater characteristics, or current treatment process.

    Or, please provide the brand or model of the product you are currently using. Our technical team will recommend the most suitable product for you.

    You can also send us samples for laboratory analysis, and we will formulate equivalent or improved products according to your needs.

     

    Do you provide OEM or private label services?

    Yes, we support customization in labeling, packaging, formulation, etc.

     

    Are your products certified?

    Yes. Our products are certified by NSF, REACH, BPR, ISO9001, ISO14001 and ISO45001. We also have national invention patents and work with partner factories for SGS testing and carbon footprint assessment.

     

    Can you help us develop new products?

    Yes, our technical team can help develop new formulas or optimize existing products.

     

    How long does it take for you to respond to inquiries?

    Reply within 12 hours on normal working days, and contact via WhatsApp/WeChat for urgent items.

     

    Can you provide complete export information?

    Can provide a full set of information such as invoice, packing list, bill of lading, certificate of origin, MSDS, COA, etc.

     

    What does after-sales service include?

    Provide after-sales technical support, complaint handling, logistics tracking, reissue or compensation for quality problems, etc.

     

    Do you provide product usage guidance?

    Yes, including instructions for use, dosing guide, technical training materials, etc.

    Write your message here and send it to us

    Products categories

    Hit enter to search or ESC to close