Sodium Benzoate

Granular

Technical / Cosmetic Grade

Sodium benzoate is the sodium salt of benzoic acid. It is a white granular powder that is soluble in water. It is bacteriostatic and fungicidal under acidic conditions. Sodium benzoate is used as a preservative in soaps, pharmaceuticals and cosmetics. It inhibits the growth of bacteria, yeast, and fungi.

Chemical Information

Chemical formula: C₆H₅COONa
Molar mass: 144.11 g/mol
CAS number: 532-32-1
Appearance: White, granules
Solubility: Highly soluble in water 62.78 g/100 mL (15 °C)
pH stability: Most effective in acidic conditions (pH < 6)
Melting Point: 410 °C

Main Uses Of Sodium Benzoate

Cosmetics & Personal Care

Preserves water-based formulations like:
- Shampoos, conditioners
- Body washes and lotions
- Facial cleansers and toners
Often used in combination with potassium sorbate or other mild preservatives

Pharmaceuticals

Used inTopical creams
Functions both as a preservative and stabilizer

Industrial Applications

Corrosion inhibitor in automotive coolants
Used in some adhesives and lubricants to preserve shelf life

Summary

Property	Detail
Function	Antimicrobial preservative
Effective pH range	Best below pH 6
Applications	cosmetics, pharma, industry
Solubility	Water-soluble
Safety	Widely accepted in regulated limits

PLEASE NOTE: This product is not for human or animal consumption.

Click here for MSDS

Click here for Specification sheet

Formulation Tip: Using Sodium Benzoate

Example: Aqueous-Based Cosmetic (e.g., Facial Toner)

Goal: Preserve a water-based cosmetic with pH ~5.0

Preservative System

Sodium benzoate – 0.2%

Potassium sorbate – 0.2%

Citric acid – adjust pH to 4.5–5.2

Procedure

Dissolve sodium benzoate and potassium sorbate into the water phase.
Adjust pH using citric acid to ensure both preservatives are active (benzoate needs pH < 6.5, sorbate best below pH 5.5).
Add other ingredients as needed (humectants, extracts, etc.).
Perform microbial challenge testing for shelf stability.

This system is mild, paraben-free, and ideal for sensitive-skin formulations.

Use Tips

Sodium benzoate works best in acidic formulations, making it ideal for facial mists, toners, micellar waters, and acidic gels.
For more neutral pH or emulsions, pair with phenoxyethanol + ethylhexylglycerin or similar blends.
Always test for microbial preservation effectiveness (challenge test or PET test).

Comparison Table: Common Preservatives

Property	Sodium Benzoate	Potassium Sorbate	Phenoxyethanol
Effective pH	≤ 6.5 (best at ≤ 5.5)	≤ 5.5	3–10
Spectrum	Yeast, fungi, some bacteria	Yeast, molds	Broad-spectrum (bacteria)
Typical use rate	0.1–0.5%	0.1–0.3%	0.5–1.0%
Water solubility	High	Moderate	Low
Regulatory	cosmetic safe	cosmetic safe	EU/US approved, max 1%
Sensory impact	Neutral at low dose	Slight tang if overused	Slight rose/ether scent
Compatibility	Good with acids	Good with acids	Soluble in glycols

Biocides