Sodium Alpha-olefin Sulfonate, known as Sodium C14-16 Olefin Sulfonate or simply AOS, ranks among the most versatile anionic surfactants found in cleaning and personal care products. Its chemical formula, C14H29SO3Na for the C14 version, represents a straight-chain structure where the sulfonate group attaches through an alpha-olefin backbone. As someone who has worked in both formulating shampoos and evaluating industrial detergents, I often come across AOS for its foaming abilities, strong detergency, and compatibility with hard water. Producers tend to start with natural or petrochemical raw materials rich in linear alpha-olefins. Through sulfonation and neutralization processes, AOS comes into being as a mix of closely related molecules, offering more than just cleaning power — it brings flexibility into the lab, onto the factory floor, and into the bottle at home.
AOS presents itself in several forms: white to off-white powder, free-flowing granules or pearls, needle-like flakes, viscous to clear liquid, and sometimes as solid cake. You run a finger through a sample and feel no oiliness or excessive dusting — much less dense than salt, with typical bulk density ranging from 0.2 to 0.4 g/cm³ for powder. Liquids roll around in the beaker, viscosity rising as the active content goes higher. In the lab, the flakes or powder dissolve quickly in water, even in colder conditions — a trait end-users appreciate when time matters. At the molecular level, each strand features the sulfonate group drawn hard to the alpha carbon in the hydrophobic tail, which sets this compound apart from other sulfonates where the group can sit elsewhere. With the main actives running from C12 to C18 in carbon length, most commercial AOS sits on C14–C16 to balance cleaning action and mildness.
Manufacturers like to keep standards tight, typically listing active matter at 35-40% for liquids and 90%-plus for solids or flakes. pH lands between 7.0 and 9.5 in solutions, allowing use in nearly neutral or slightly alkaline products without the need for hefty additives. Ash content, which hints at inorganic leftovers, stays low. Water content rarely wanders far from specification, so shelf-stability holds up for months if protected from moisture. The Harmonized System code (HS Code) generally tracks under 3402.11.00, making import-export paperwork in line with international chemical trade. Each bag or drum bears clear batch numbers, production dates, and key details on reactivity and compatibility with other raw materials.
In personal care, where consumers seek foam, lather, and gentleness, AOS slips into liquid hand soap, bubble bath, shampoos, and facial cleansers. Its low skin irritation compares favorably with traditional lauryl sulfate salts. In my years evaluating surfactants, I saw AOS often replace harsher agents in children’s cleansing formulas, thanks to a much milder impact on the skin barrier. On the industrial side, AOS steps up in textile processing as a wetting agent, in dish washing, car washing, and even metal cleaning because of its strong emulsification and rapid wetting. The powder or flakes dissolve quickly into bulk solutions, speeding up blending lines and reducing downtime — crucial for factories trying to shave operational costs. Even with hard water, you don’t see much precipitation, so residues and build-up on washed items drop to a minimum. The product’s stable performance in a wide pH range keeps it dependable, whether you mix it with caustics, citric acid, or strong builders.
With any surfactant, the conversation about safety stands front and center. Material Safety Data Sheets (MSDS) call out skin and eye irritation risk, especially with concentrated AOS powder or highly active solutions. In my work, I always stress the need for gloves, safety goggles, and good ventilation when handling bulk AOS or mixing solutions. If someone gets it in their eyes, rinse immediately with running water and seek medical advice. Accidental spills of liquid or powder on factory floors need prompt sweeping and washing down to prevent slips and airborne dust. Storage away from strong oxidizers and acids keeps reactivity under control. For disposal, AOS sits in a better place than some older surfactants, thanks to its ready biodegradability and low aquatic toxicity at use levels. Still, high concentrations entering wastewater streams can cause foaming in treatment plants, so responsible manufacturers always keep containment and process controls in place.
Access to consistent, high-quality AOS is non-trivial for smaller producers, especially those outside major chemical hubs. Maintaining specifications batch after batch requires disciplined raw material supply and modern reactors. Technical teams who monitor blending, particle sizing for powders, and storage of liquid forms must keep vigilant. Supply chain disruptions — as seen during global transport slowdowns — highlight the need to source AOS from multiple, vetted suppliers. Alternatives exist, but swapping out a workhorse like AOS isn’t simple in established cleaning or care formulas because of the balance between cost, foam, and user experience. Training workers in safe handling, supporting strict product labeling, and using closed systems for transferring powder or liquid all help reduce near-term safety risks while upholding long-term trust with downstream brands and consumers. Investing in on-site testing tools lets plants check the real active content, pH, and water level, sidestepping surprises from off-spec batches.
Sodium Alpha-olefin Sulfonate keeps proving itself among chemists and industrial users. Its combination of high detergency, foam stability, ease of formulation, and mild profile suits the shifting demands of modern consumers and regulatory bodies. Upgrades in surfactant plants across Asia, Europe, and the Americas mean supply remains abundant, but attention to the basics — safe handling, clear labeling, rigorous quality checks — underpins the trust this material has built over decades in the world’s supply chain. As more cleaning and personal care producers seek mild, high-performing raw materials, AOS holds its position not just because it is old, but because it keeps meeting the mark across thousands of products, industries, and real-world application needs.
