Sodium Laureth Sulfate (SLES)
CAS Number: 68585-34-2 or 9004-82-4 (depending on ethoxylation level)
Chemical Name: Sodium lauryl ether sulfate
Common Name: SLES
Other Names: Sodium lauryl ether sulfate, Sodium polyoxyethylene lauryl sulfate, Ether sulfate
Chemical Formula: C₁₂H₂₅(OCH₂CH₂)nOSO₃Na(where n typically = 1–3 ethylene oxide units)
Appearance: Clear to slightly yellow liquid
Odor: Mild, characteristic
Active Content: 28%–70% (typically 70% or 30%)
Solubility: Easily soluble in water
Viscosity (70%): 2,000–10,000 cps
Biodegradability: Readily biodegradable
pH (1% solution): 6.5 – 8.5
Application in areas:
SLES is a widely used anionic surfactant, known for its foaming, emulsifying, and cleansing properties. Common applications include:
- Personal Care & Cosmetics
- Shampoos
- Body washes
- Facial cleansers
- Toothpastes
- Bubble baths
- Household & Industrial Cleaning
- Liquid dishwashing detergents
- Laundry liquids
- All-purpose cleaners
- Hard surface cleaners
- Toilet Soaps & Syndet Bars
- Added to improve foam and cleansing power in combination with soap noodles
Production Process:
SLES is synthesized through two main steps:
- Ethoxylation of lauryl alcohol (C₁₂H₂₅OH) using ethylene oxide (EO) → Forms laureth (lauryl ether)
- Sulfation with sulfur trioxide (SO₃) or chlorosulfonic acid, followed by neutralization with sodium hydroxide
Safety & Handling:
- Skin & eye irritant: Use gloves, avoid direct contact
- Mild toxicity: Non-toxic at typical concentrations
- Not carcinogenic: Safer than SLS (Sodium Lauryl Sulfate)
- Proper storage: Store in sealed HDPE drums or IBCs
Commercial Specs:
| Form | Concentration | Packaging |
| Clear viscous liquid | 28%–70% active | 200 kg drum, IBC, bulk |
| Paste (70%) | High viscosity | Heated tanks needed |
Advantages Over SLS:
- Acid-resistant gloves (nitrile or neoprene)
- Chemical splash goggles / face shield
- Lab coat or acid-resistant apron
- Proper ventilation / fume hood