LABSA 96%: Specification, Uses in Detergents and How to Check Quality
What active matter, free acid, free oil and Klett colour tell you about a batch
LABSA (linear alkyl benzene sulphonic acid, often called acid slurry) is the most widely used surfactant raw material in the detergent industry. Almost every detergent powder, washing cake and dishwash liquid on an Indian shop shelf starts with it. Buying it well comes down to understanding a handful of numbers on its Certificate of Analysis.
What LABSA is and how it is made
LABSA is made by sulphonating linear alkylbenzene (LAB), typically with C10 to C13 alkyl chains, using sulphur trioxide. The result is a brown, viscous acid. When it is neutralised with an alkali such as caustic soda or soda ash, it becomes LAS (linear alkylbenzene sulphonate), the anionic surfactant that does the cleaning.
| Term | What it is |
|---|---|
| LAB | Linear alkylbenzene, the raw material |
| LABSA | The sulphonic acid made from LAB, sold as "LABSA 90%" or "LABSA 96%" |
| LAS | The neutralised salt (usually sodium) that acts as the surfactant in the product |
The key specifications, explained
Active matter
The percentage of sulphonic acid in the product. "LABSA 96%" means about 96% active matter. Higher active matter means more surfactant per kilogram bought.
Free acid (as H₂SO₄)
Residual sulphuric acid from sulphonation. It consumes alkali during neutralisation and ends up as sodium sulphate filler, so lower is better.
Free oil (NDOM)
Non-detergent organic matter, mostly unreacted LAB. High free oil means less cleaning power and can affect odour and clarity, especially in liquid detergents.
Colour (Klett)
Measured on a diluted solution; a lower Klett number means a lighter product. Colour matters most for transparent liquid detergents and dishwash gels.
Indian Standard: IS 8401
IS 8401 (alkyl benzene sulphonic acid, acid slurry) sets two types. For the high-active Type 1, the limits include:
| Parameter | IS 8401, Type 1 limit |
|---|---|
| Active matter | Minimum 95.0% |
| Free sulphuric acid | Maximum 2.0% |
| Free oil (free alkyl benzene) | Maximum 2.0% |
| Colour, 5% active matter solution (Klett) | Maximum 950 |
These are minimum national requirements. Detergent makers often agree tighter commercial limits with their supplier, especially on colour for liquid products. Write your limits on the purchase order.
Where LABSA is used
- Detergent powders: neutralised with soda ash, either in slurry or by dry neutralisation.
- Detergent cakes and bars: the main active in most washing cakes.
- Liquid detergents and dishwash liquids: neutralised with caustic soda or other alkalis.
- Household and industrial cleaners: floor cleaners, degreasers and all-purpose cleaners.
- Other industries: wetting and emulsifying in textile processing and, as calcium salts, in agrochemical emulsifiable concentrates.
How much alkali does LABSA need?
A practical rule of thumb, taking the molar mass of the sulphonic acid as about 320 g/mol (the value IS 8401 uses):
- 100 kg of LABSA with 96% active matter contains about 0.30 kmol of sulphonic acid, which needs about 12 kg of caustic soda (100% basis) to neutralise.
- Each 1% of free sulphuric acid adds roughly 0.8 kg of caustic soda per 100 kg of LABSA.
- With soda ash instead, multiply the caustic figure by about 1.33.
Always confirm the final dose against pH in your own process; these figures are a starting point.
Storage, handling and packing
- LABSA is a strong acid and corrosive to skin and eyes. Use acid-resistant gloves, goggles and protective clothing, and keep eyewash at hand.
- Store in closed HDPE or suitably lined or stainless-steel containers, away from heat, moisture and alkalis.
- It is supplied in HDPE drums and in bulk tankers. Keep drums closed to stop it absorbing moisture.
- Follow the Safety Data Sheet for spill handling and disposal.
Frequently asked questions
What does LABSA 96% mean?
It means the product contains about 96% active matter (sulphonic acid). The rest is mainly free sulphuric acid, free oil and a little water.
What is the difference between LABSA 90% and LABSA 96%?
The 96% grade has more surfactant and less free acid and free oil per kilogram, so it needs less product for the same active content. Compare offers on cost per kilogram of active matter.
What is a good Klett colour for liquid detergent?
For clear liquids, buyers generally look for a low Klett value. Agree a maximum with your supplier and check it on every COA.
Is LABSA biodegradable?
Its neutralised form, LAS, is a linear-chain surfactant, which is why it replaced older branched alkylbenzene sulphonates that biodegraded poorly.
Source it from Lithionyx Chemicals
We supply LABSA to manufacturers across India, with export on order. Every batch ships with the manufacturer's Certificate of Analysis and Safety Data Sheet, and we confirm grade, packing and dispatch before we quote. See the LABSA product page, use the Request a Quote button, or write to hello@lithionyx.com. Our team replies within one business day.
