CAS Number:
8001-54-5. Also listed under 63449-41-2 for specific compositions.
Chem/IUPAC Name:
Benzalkonium chloride (BKC, BAC)
Common Product Code:
BC50, BAC50
Molecular Formula:
Commonly represented as C21H38ClN for the C12 (dodecyl) chain component.
Molecular Weight:
339.98 - 340.00 g/mol
Common Synonyms:
Alkyldimethylbenzylammonium chloride (ADBAC), Quaternary ammonium compound.
Uses:
It is a concentrated aqueous solution of a cationic surfactant from the quaternary ammonium compound family. It is a powerful and broad-spectrum biocide, disinfectant, and preservative. It acts by disrupting microbial cell membranes. Common applications include:
· Disinfection & Sanitization: Active ingredient in hospital-grade surface disinfectants, hand sanitizers, and antiseptic wipes.
· Pharmaceutical & Personal Care Preservative: Used in eye/ear/nasal drops, shampoos, wet wipes, and cosmetics at very low final concentrations.
· Industrial Applications: Used as a phase-transfer catalyst, algaecide in water treatment, and corrosion inhibitor.
Origin:
It is a semi-synthetic organic salt. Industrially produced by reacting alkyl dimethyl amines (with C8-C18 chains) with benzyl chloride. The 50% solution is typically purely aqueous.
What does Benzalkonium Chloride 50% do in a formulation?
Primary Functions in a Formulation:
- Antimicrobial Agent / Biocide: Primary function; kills bacteria, fungi, algae, and enveloped viruses.
- Preservative: Prevents microbial growth in aqueous products.
- Cationic Surfactant: Provides emulsifying, antistatic, and cleaning properties.
- Phase Transfer Agent: Facilitates reactions in chemical synthesis.
Safety Profile:
· Hazard Classification: D. Classified as corrosive, causing severe skin burns, eye damage, and toxic if swallowed. It is also hazardous to aquatic life.
· Irritation & Sensitization: A severe skin and eye irritant. A maximum concentration of 0.1% is considered non-irritating to intact skin.
· Key Considerations:
· NEVER use the concentrated solution directly on skin or eyes. It is for dilution only.
· Can cause respiratory irritation and has been linked to occupational asthma.
· Incompatible with soaps, anionic detergents, strong oxidizing agents, and certain metals.
Technical profile:
| Property | Values |
| Appearance | Clear, colorless to pale yellow viscous liquid |
| Active Content | 47.5% - 52.5% w/v (50% solution) |
| Odor | Slight aromatic odor |
| Specific Gravity / Density | ~0.98 g/cm³ at 20°C |
| pH | Aqueous solutions are neutral to slightly alkaline |
| Typical Composition | A mixture primarily of C12 (dodecyl, ~40-70%) and C14 (tetradecyl, ~20-40%) alkyl chain derivatives |
| Solubility | Miscible with water and lower alcohols (methanol, ethanol). Immiscible with ether |
| Storage & Stability | · Store at controlled room temperature (15-25°C is common). · Low-Temperature Note: May form a gel or precipitate if stored below ~15°C. · Shelf Life: Up to 5 years when stored properly |