Sodium Dichloroisocyanurate (SDIC) is a versatile chlorine-release disinfectant and oxidizing agent, typically appearing as a white crystalline powder or granular solid with a slight chlorine odor.
Primary Applications
SDIC is used across a wide range of fields due to its high available chlorine content (typically ≥56%):
Water Treatment: A primary use is for disinfection in swimming pools, spas, and drinking water. It is also applied in industrial circulating cooling water systems to prevent microbial growth and biofilm, and in wastewater pretreatment.
General Disinfection: Its broad-spectrum biocidal activity, effective against bacteria, fungi, and viruses, makes it suitable for disinfecting surfaces in hospitals, hotels, food processing plants, and farms.
Other Industrial Uses:
Textile Industry: Used as a bleaching agent and as a shrink-proofing agent for wool (often under the name Basolan DC).
Emerging Applications: Recent research explores its use in sludge treatment to enhance hydrogen production and in TEMPO-mediated oxidation for cellulose nanomaterial production.
Key Properties & Handling
Parameter Specification
Chemical Formula C₃Cl₂N₃NaO₃
CAS Number 2893-78-9
Appearance White crystalline powder, granules, or tablets
Solubility Very soluble in water (~250 g/L at 25°C), upon which it hydrolyzes to release chlorine
pH (1% solution) 5.5 – 7.0
Available Chlorine Typically ≥ 56% – 60%
Safety & Storage
Chemical Reactivity: SDIC is a powerful oxidizer. It can promote the combustion of flammable materials (paper, oil, organics) and may react violently with strong acids, releasing chlorine gas. Contact with nitrogenous compounds (e.g., ammonia, urea) can produce explosive nitrogen trichloride.
Decomposition: When heated above 220-240°C, it decomposes, releasing toxic fumes of nitrogen oxides and chlorine. In the presence of moisture, it can be corrosive to metals.
Storage: It must be stored in a cool, dry, and well-ventilated area, away from heat, moisture, acids, and all combustible or nitrogenous materials. Common packaging includes 25 kg bags, 50 kg fiber drums, or IBC totes.