Sodium hydrosulfite 88%

Sodium hydrosulfite, also known as sodium dithionite (Na₂S₂O₄), is a white to yellowish crystalline powder that is widely used as a strong reducing agent in various industrial and chemical applications. The 88% grade indicates that the product contains approximately 88% active sodium dithionite, with the remainder typically consisting of inert fillers or stabilizers such as sodium chloride or sodium sulfate, which help improve storage stability and handling safety. This compound is highly water-soluble and decomposes readily in moist air or acidic conditions, releasing sulfur dioxide (SO₂). Due to its instability in the presence of oxygen and moisture, it is usually stored in airtight, moisture-proof containers under an inert atmosphere when possible.

 

One of the primary uses of 88% sodium hydrosulfite is in the textile industry, where it serves as a bleaching agent for cotton, wool, and other natural fibers. It is particularly effective in vat dyeing processes, helping to reduce insoluble vat dyes into their soluble leuco forms so they can be applied evenly to fabrics. After oxidation, the dye reverts to its insoluble state, ensuring excellent colorfastness. In addition to textiles, it is employed in the paper and pulp industry for the bleaching of mechanical and chemical pulps, contributing to brighter, higher-quality paper products without significant fiber degradation.

 

Sodium hydrosulfite is also utilized in water treatment, organic synthesis, and as a dechlorinating agent. In environmental applications, it helps neutralize chlorine and other oxidizing agents in wastewater. Its powerful reducing capability makes it valuable in chemical laboratories for oxygen scavenging and in the regeneration of certain catalysts. However, due to its reactivity, proper safety precautions are essential during handling—use of protective equipment, adequate ventilation, and avoidance of contact with acids or oxidizing agents are critical to prevent hazardous reactions, including fire or release of toxic gases.

 

Despite its utility, sodium hydrosulfite should be handled with care, as it can cause skin and respiratory irritation. The 88% concentration offers a balance between efficacy and stability, making it a preferred choice in many industrial settings where consistent performance and manageable shelf life are required.