Sodium alkyl naphthalene sulfonate, also known as sodium alkylnaphthalenesulfonate or SANS, is a class of anionic surfactants that are widely used in various industrial applications. These surfactants are derived from naphthalene and are known for their excellent wetting, dispersing, and emulsifying properties.

1.Powder Form

Property Value

Appearance White/Beige Powder

Active Content (%) 60-80

pH (10% solution) 5-8

Bulk Density (g/ml) 0.50-0.70

Loss on Drying (%) ≤10

Sulfate Content (%) 15-30

Water Solubility Excellent

2. Liquid Form

Property Value

Appearance Liquid, dark brown

Active Content (%) 60-80

pH (10% solution) 5-8

Viscosity (at 25°C, mPa.s) 200-1000

Density (at 25°C, kg/L) 1.10-1.30

Flash Point (°C) >100

Solubility in Water Soluble

Sulfate Content (%) 15-30

Some key points about sodium alkyl naphthalene sulfonates:

  1. Applications:
    • Textile industry: Used as wetting agents, leveling agents, and dye dispersants in dyeing and finishing processes.
    • Detergents and cleaners: Employed as surfactants in household and industrial cleaners, dishwashing liquids, and laundry detergents.
    • Concrete admixtures: Added to concrete mixes to improve workability, dispersibility, and air entrainment.
    • Oil and gas industry: Used as emulsifiers, wetting agents, and dispersants in drilling fluids and enhanced oil recovery processes.
    • Paints and coatings: Incorporated as wetting agents, dispersants, and emulsifiers in various paint formulations.
  2. Structure: They are produced by sulfonating naphthalene with an alkyl group, typically a linear or branched alkyl chain ranging from C6 to C16. The resulting molecule has a hydrophobic alkyl chain and a hydrophilic sulfonate group, giving it its surfactant properties.
  3. Properties:
    • Good wetting and dispersing abilities
    • Excellent emulsifying and solubilizing properties
    • Resistance to hard water and electrolytes
    • Thermal stability
    • Biodegradability (varies depending on the alkyl chain length)
  4. Environmental considerations: While SANS are generally considered biodegradable, their environmental impact depends on factors such as alkyl chain length and concentration. Proper handling and disposal practices are necessary to minimize their potential adverse effects on aquatic ecosystems.

Sodium alkyl naphthalene sulfonates are versatile surfactants widely employed in various industries due to their unique properties and performance.