SODIUM COCO-SULFATE

Sodium coco‑sulfate (SCS) is an anionic surfactant widely used in personal care and cleaning formulations. 
It is produced by sulfation of mixed fatty alcohols or fatty acid derivatives derived predominantly from coconut oil, and subsequent neutralization to yield the sodium salt. 
SCS is valued for strong detergency, high foaming, and cost‑effectiveness; however, it also shares many functional and safety characteristics with other alkyl sulfate surfactants (notably sodium lauryl sulfate, SLS). 
This article presents an extensive review of SCS: identity and synonyms (including common CAS entries), production routes and raw materials, comprehensive chemical and physical properties, analytical methods for identification and purity, formulation uses and performance characteristics, toxicology and ecotoxicology, regulatory context, environmental fate and biodegradation, industrial handling and worker safety, comparative discussion with SLS/SLES and alternative surfactants, case studies, and practical guidance for formulators and regulators.

Anionic sulfate surfactants have been the backbone of detergency technology for over a century. 
The classic member sodium lauryl sulfate (SLS) was among the earliest widely commercialized alkyl sulfates. 
Over time, variations and mixtures of alkyl chain lengths were developed to adapt performance and raw-material sourcing. 
Sodium coco‑sulfate (SCS) emerged as a commercial product produced from the mixed C12–C18 fatty fractions of coconut oil (and related feedstocks). 
Its development responds to market demand for plant‑derived feedstocks and to provide surfactant functionality resembling SLS while utilizing the full coconut fatty acid/ alcohol distribution rather than a purified lauryl fraction.

Historically, SCS has been used widely in bar soaps, syndet bars, shampoos and shower gels. Marketing in the natural/organic personal care sector often highlights SCS as derived from coconut oil and (incorrectly or ambiguously) positions it as a milder alternative to pure SLS. 
The scientific and regulatory communities, however, treat SCS as an alkyl sulfate mixture whose functional and toxicological profile depends on composition and degree of purification.

Chemical identity, nomenclature and synonyms (including CAS)
INCI name: Sodium Coco‑Sulfate (also written Sodium Coco‑Sulphate)
IUPAC / descriptive names: sodium salt of sulfuric acid, mono‑C12‑18‑alkyl esters (typical description)
Common synonyms: Sodium coconut sulfate; sulfuric acid, mono‑C12‑18‑alkyl esters, sodium salts; sodium coco sulphate; sodium cocoyl sulfate (sometimes used erroneously for related derivatives);
Reported CAS registry numbers: multiple CAS numbers appear in commercial and regulatory documents due to differing manufacturing descriptions and mixture cataloguing. 
Representative CAS entries frequently encountered in supplier documentation and SDSs include:
68955‑19‑1 — often used to identify sulfuric acid mono‑C12‑18 alkyl esters, sodium salts (a broad descriptor used in SDS and technical data sheets).
97375‑27‑4 (and variations reported as 097375‑27‑4) — used by some suppliers and product listings to identify sodium coco‑sulfate products.
Because SCS is a complex mixture rather than a single discrete molecular entity, CAS assignments can vary between suppliers and registries; formulators and regulators should therefore verify the CAS on the supplier’s certificate of analysis and SDS for the particular grade being purchased.
EC / EINECS numbers: several product listings report EC or EINECS numbers tied to the mixture; again these are supplier/mixture specific and should be confirmed per product batch.
(Note: SDS and supplier documentation often include the descriptive chemical name “Sulfuric acid, mono‑C12‑18 alkyl esters, sodium salts” as the compositional identity.)

Raw materials and production methods
Raw materials
Primary feedstocks for SCS production are coconut oil fractions (coconut fatty acids or fatty alcohols) and reacting agents used to introduce the sulfate group (sulfation agents). 
The coconut fraction contains a mixture of fatty acids: predominantly lauric acid (C12), with significant amounts of C8, C10, C14, C16 and C18 species, depending on fractionation.

Sulfation chemistries
Two general industrial routes are common:
Direct sulfation of fatty alcohols — long‑chain alcohols (C12–C18) are sulfated using reagents such as chlorosulfonic acid, sulfur trioxide (SO3) in an organic carrier, or sulfuric acid to yield alkyl sulfate esters, followed by neutralization with sodium hydroxide to form the sodium salt. 
Sulfation with SO3 or specialized sulfation reagents is common at scale for control of degree of sulfation and byproduct minimization.
Sulfation of fatty acid derivatives (esters) — fatty acid esters may be converted to sulfate esters under appropriate conditions; alternatively, fatty acids can be converted to alcohols and then sulfated.

Purification and forms
SCS is supplied in multiple physical forms: powders (granules or needle crystals), flakes, pastes, and aqueous solutions. 
Purity grades (e.g., 70% vs 95% active matter) affect handling, dissolution rates, and formulation dose. Impurities may include unreacted alcohols, residual sulfuric acid, sodium sulfate, and short‑chain materials. 
Quality control ensures active matter, pH and residuals meet specification.

Chemical structure and composition (mixture nature)
Sodium coco‑sulfate is not a single molecular species but a mixture of sodium sulfate esters of varying alkyl chain lengths (C8–C18, variable distribution). 
The dominant component is typically the C12 (lauryl) sulfate ester but significant proportions of C14, C16, and C18 sulfates are present. This distribution governs many functional differences between SCS and pure SLS (which is essentially the C12 homolog).

Molecular descriptors
A generalized structural fragment: R–O–SO3–Na (where R is an alkyl chain of ~C8–C18). 
The sodium salt is the anionic surfactant that dissociates in water to yield the R–O–SO3^- anion and Na+.

Physical and chemical properties
Properties vary by grade; typical ranges:
Appearance: white to off‑white powder/needles, or viscous paste for lower active matter grades.
Active matter (typical): 70% (commodity) to 95% (high‑active) solids.
Odor: faint to characteristic slight fatty odor.
Solubility: readily soluble in water, forming clear to slightly opalescent solutions depending on grade and concentration; soluble in lower alcohols; insoluble in hydrocarbon solvents.
pH (1% aqueous): typically 9–11 when neutralized to the sodium salt; pH depends on residual alkaline or acidic species.
Melting/softening point: solid forms show needle melting or softening rather than a precise melting point due to mixture nature.
Foaming and surface tension reduction: strong foaming at low concentrations; critical micelle concentration (CMC) and surface tension depend on chain distribution and counterion.
Quantitative physical constants are mixture‑dependent and should be provided by the supplier’s technical data sheet for each grade.

Analytical methods and quality control
Because SCS is a mixture, analytical characterization relies on a combination of techniques:
HPLC/LC (after suitable derivatization): for profiling alkyl chain distribution.
GCMS: often after hydrolysis and conversion to volatile derivatives to identify fatty acid/alcohol composition.
FT‑IR: to confirm sulfate ester functionality.
Ion chromatography: to quantify sulfate and free anion species.
Titration: to determine active matter content (acid‑base titration after hydrolysis) or total sulfated equivalents.
Elemental analysis/ICP: to test for sodium and traces of metals.
Karl Fischer: for moisture content.
Quality control specifications typically include active matter (%), moisture, pH, sulfur content, sodium sulfate limits, and heavy metals.

Mechanism of surfactant action and surface chemistry
SCS molecules adsorb at interfaces with hydrophobic alkyl chains extending into oil or air and the anionic headgroup remaining in water, reducing surface tension and forming micelles above CMC. 
Micelles solubilize oils and particulate soils; charged headgroups impart electrostatic stabilization of micelles and particle dispersions. 
The mixed‑chain distribution influences micellar size, Krafft temperature, and CMC, and therefore performance in foaming and detergency.

SAFETY INFORMATION ABOUT SODIUM COCO-SULFATE

First aid measures:
Description of first aid measures:
General advice:
Consult a physician. 
Show this safety data sheet to the doctor in attendance.
Move out of dangerous area:
 
If inhaled:
If breathed in, move person into fresh air. 
If not breathing, give artificial respiration.
Consult a physician.
In case of skin contact:
Take off contaminated clothing and shoes immediately. 
Wash off with soap and plenty of water.
Consult a physician.
 
In case of eye contact:
Rinse thoroughly with plenty of water for at least 15 minutes and consult a physician.
Continue rinsing eyes during transport to hospital.
 
If swallowed:
Do NOT induce vomiting. 
Never give anything by mouth to an unconscious person. 
Rinse mouth with water. 
Consult a physician.
 
Firefighting measures:
Extinguishing media:
Suitable extinguishing media:
Use water spray, alcohol-resistant foam, dry chemical or carbon dioxide.
Special hazards arising from the substance or mixture
Carbon oxides, Nitrogen oxides (NOx), Hydrogen chloride gas
 
Advice for firefighters:
Wear self-contained breathing apparatus for firefighting if necessary.
Accidental release measures:
Personal precautions, protective equipment and emergency procedures
Use personal protective equipment. 
 
Avoid breathing vapours, mist or gas. 
Evacuate personnel to safe areas.
 
Environmental precautions:
Prevent further leakage or spillage if safe to do so.
Do not let product enter drains.
Discharge into the environment must be avoided.
 
Methods and materials for containment and cleaning up:
Soak up with inert absorbent material and dispose of as hazardous waste. 
Keep in suitable, closed containers for disposal.
 
Handling and storage:
Precautions for safe handling:
Avoid inhalation of vapour or mist.
 
Conditions for safe storage, including any incompatibilities:
Keep container tightly closed in a dry and well-ventilated place. 
Containers which are opened must be carefully resealed and kept upright to prevent leakage.
Storage class (TRGS 510): 8A: Combustible, corrosive hazardous materials
 
Exposure controls/personal protection:
Control parameters:
Components with workplace control parameters
Contains no substances with occupational exposure limit values.
Exposure controls:
Appropriate engineering controls:
Handle in accordance with good industrial hygiene and safety practice.
Wash hands before breaks and at the end of workday.
 
Personal protective equipment:
Eye/face protection:
Tightly fitting safety goggles. 
Faceshield (8-inch minimum). 
Use equipment for eye protection tested and approved under appropriate government standards such as NIOSH (US) or EN 166(EU).
 
Skin protection:
Handle with gloves. 
Gloves must be inspected prior to use. 
Use proper glove
removal technique (without touching glove's outer surface) to avoid skin contact with this product. 
Dispose of contaminated gloves after use in accordance with applicable laws and good laboratory practices. 
Wash and dry hands.
 
Full contact:
Material: Nitrile rubber
Minimum layer thickness: 0.11 mm
Break through time: 480 min
Material tested:Dermatril (KCL 740 / Aldrich Z677272, Size M)
Splash contact
Material: Nitrile rubber
Minimum layer thickness: 0.11 mm
Break through time: 480 min
Material tested:Dermatril (KCL 740 / Aldrich Z677272, Size M)
It should not be construed as offering an approval for any specific use scenario.
 
Body Protection:
Complete suit protecting against chemicals, The type of protective equipment must be selected according to the concentration and amount of the dangerous substance at the specific workplace.
Respiratory protection:
Where risk assessment shows air-purifying respirators are appropriate use a fullface respirator with multi-purpose combination (US) or type ABEK (EN 14387) respirator cartridges as a backup to engineering controls. 
 
If the respirator is the sole means of protection, use a full-face supplied air respirator. 
Use respirators and components tested and approved under appropriate government standards such as NIOSH (US) or CEN (EU).
Control of environmental exposure
Prevent further leakage or spillage if safe to do so. 
Do not let product enter drains.
Discharge into the environment must be avoided.
 
Stability and reactivity:
Chemical stability:
Stable under recommended storage conditions.
Incompatible materials:
Strong oxidizing agents:
Hazardous decomposition products:
Hazardous decomposition products formed under fire conditions. 
Carbon oxides, Nitrogen oxides (NOx), Hydrogen chloride gas.
 
Disposal considerations:
Waste treatment methods:
Product:
Offer surplus and non-recyclable solutions to a licensed disposal company. 
Contact a licensed professional waste disposal service to dispose of this material.
Contaminated packaging:
Dispose of as unused product