Sodium Acetate, with the chemical formula CH₃COONa, is the sodium salt of acetic acid. It appears as a white crystalline powder, odorless or with a mild vinegar-like smell (especially when heated). Sodium acetate is moderately hygroscopic, particularly in its anhydrous form. It is available in two forms: anhydrous and hydrated (commonly the trihydrate form, CH₃COONa·3H₂O).

Structure of Sodium Acetate

Sodium acetate is an ionic compound composed of a sodium cation (Na⁺) and an acetate anion (CH₃COO⁻). The acetate ion consists of a methyl group (CH₃) bonded to a carboxylate group (COO⁻). In the carboxylate group, the double bond between carbon and oxygen exhibits resonance, meaning the negative charge is delocalized over the two oxygen atoms.

Chemical Formula: CH₃COONa
Resonance Structure: O=C–O⁻ ⇄ ⁻O–C=O

Properties of Sodium Acetate

• Appearance: White crystalline powder

• Odor: Odorless; may release a vinegar-like smell when heated

• Solubility: Highly soluble in water; moderately soluble in ethanol (~1.4 g/100 mL)

• Hygroscopicity: Anhydrous form absorbs moisture from the air

• Basic Nature: As the salt of a weak acid and strong base (NaOH), its aqueous solution is slightly alkaline (pH ~8–9 for a 0.1 M solution)

• Melting Point: Anhydrous form decomposes around 324°C; trihydrate melts at ~58°C, releasing water of crystallization

• Buffering Properties: In combination with acetic acid, it forms a buffer solution effective within a pH range of 4 to 6.5

• Chemical Behavior: Can release gases such as acetic acid or CO₂ when in contact with strong acids or oxidizing agents

Applications of Sodium Acetate

Food Industry

• Used as a food additive (E262) for pH regulation, providing a salty/sour taste, and as a preservative

• Acts as an antibacterial and antifungal agent in some food formulations

Pharmaceutical and Medical

• Serves as a sodium source in IV injections or dialysis solutions

• Functions as a buffer component in drug formulations and biological reactions

Textile Industry

• Used in dye baths to control pH and aid in dye uptake

• Neutralizes residual acids like H₂SO₄

• Helps prevent static electricity buildup

Construction Industry

• Acts as an additive to control pH and improve freeze resistance in concrete (e.g., in sealants)

Laboratory Use

• Employed in buffer preparation (especially in biochemistry and DNA extraction)

• Used as a carbon source in bacterial culture media

• Forms part of extraction buffers in molecular biology

Hand Warmers and Heating Pads

• Utilizes supersaturated sodium acetate trihydrate solution that releases latent heat (~264–289 kJ/kg) upon sudden crystallization

Other Uses

• Delays curing in chloroprene rubber production

• Used in leather tanning and dye manufacturing

Advantages of Sodium Acetate

• Generally safe for food use as approved by the FDA in regulated amounts

• Effective buffering capacity

• Highly compatible with industrial processes

• Low cost

• Preservative effect (antimicrobial)

• Useful in phase-change thermal storage systems

Disadvantages of Sodium Acetate

• Moderately hygroscopic (especially in anhydrous form) → requires airtight storage

• Irritant to eyes and skin upon contact

• Dust inhalation may cause respiratory irritation

• Ingestion in high amounts may lead to digestive upset or hypernatremia

• Thermal decomposition at high temperatures may release irritating vapors

• Caution in patients with kidney or heart issues due to electrolyte imbalances

• Pharmaceutical forms may contain aluminum or other excipients; special care is needed in premature infants or patients with renal insufficiency

Sodium Diacetate (NaH(C₂H₃O₂)₂) is a double salt composed of sodium acetate and acetic acid, widely recognized as a versatile food additive. Registered under CAS No. 126-96-5, it appears as a white crystalline powder with a mild vinegar-like odor. Sodium diacetate exhibits antimicrobial properties and serves as an acidity regulator, making it highly useful in the food, pharmaceutical, and chemical industries.

Chemical Structure of Sodium Diacetate

• Chemical formula: NaH(C₂H₃O₂)₂

• Composition: Formed by the reaction of sodium acetate and acetic acid

• Functional group: Double salt of acetic acid

• Appearance: White crystalline solid with a faint acetic acid odor

• Solubility: Soluble in water and stable under ambient conditions

The structure allows sodium diacetate to act not only as a buffering agent but also as a slow-release source of acetic acid.

Physical and Chemical Properties of Sodium Diacetate

Grades of Sodium Diacetate

1. Food Grade Sodium Diacetate

• Approved food additive (E262(ii))

• Functions as an acidity regulator, antimicrobial, and preservative

• Widely used in bakery, meat, and dairy industries

2. Pharmaceutical Grade Sodium Diacetate

• Used as an excipient in pharmaceutical formulations

• Provides antimicrobial protection and pH control in drug manufacturing

3. Industrial Grade Sodium Diacetate

• Used in chemical processes, animal feed, and odor control

• Exhibits antifungal and antimicrobial effects in non-food applications

Applications of Sodium Diacetate

1. Food Industry

• Preservative and Antimicrobial Agent: Prevents mold and bacterial growth in bread, cakes, and baked goods.

• Acidity Regulator: Controls pH in sauces, dressings, and beverages.

• Flavor Enhancer: Imparts a mild vinegar-like taste to snacks, chips, and processed foods.

• Shelf-life Extension: Widely used as food additive E262(ii) to extend product freshness.

2. Pharmaceutical Industry

• Used in antiseptic formulations and personal care products.

• Contributes to microbial control in pharmaceutical compositions.

3. Animal Feed

• Acts as an antimicrobial additive in livestock and poultry feed.

• Enhances feed safety and prevents spoilage.

4. Chemical Industry

• Serves as a deodorizing and antifungal agent in various products.

• Applied in specialized chemical formulations.

Advantages of Sodium Diacetate

✅ High safety for food and pharmaceutical uses (approved by FDA and EFSA)
✅ Multifunctional — applicable across food, pharmaceutical, and industrial sectors
✅ Strong antimicrobial activity against molds and bacteria
✅ Enhances food shelf life and reduces waste
✅ Improves flavor with a mild vinegar profile

Disadvantages of Sodium Diacetate

⚠️ Excessive use can result in an overly strong or unpleasant flavor
⚠️ High concentrations may cause gastric irritation
⚠️ Hygroscopic — readily absorbs moisture in humid environments

Safety and Storage Guidelines

• Store in airtight, moisture-resistant containers

• Keep away from direct sunlight, in a cool, dry environment

• Use protective gloves and goggles in industrial handling

• Follow approved dosage limits for food applications (E262 standard)

Sodium Diacetate Production Process

1. Step 1 – Sodium Acetate Production:
   Reaction of acetic acid with sodium carbonate or sodium hydroxide.

2. Step 2 – Addition of Extra Acetic Acid:
   Sodium acetate reacts with excess acetic acid to form the double salt (sodium diacetate).

3. Step 3 – Cooling and Crystallization:
   The resulting solution is cooled, allowing sodium diacetate crystals to form.

4. Step 4 – Drying and Packaging:
   The dried crystals are processed into a fine white powder and packaged for commercial use.

Technical Specifications of Sodium Diacetate

Purchasing Sodium Diacetate

To purchase high-quality sodium diacetate and get the best pricing, it’s important to choose a reliable supplier.
Tamin Kala Tak Co., with years of experience in supplying raw materials for the food, pharmaceutical, and chemical industries, offers sodium diacetate in multiple grades.
Contact our experts today for orders and price inquiries.

❓ Frequently Asked Questions  Sodium Diacetate

1. What is Sodium Diacetate?
A double salt of sodium acetate and acetic acid, used as a food additive, antimicrobial, and acidity regulator.

2. What’s the difference between Sodium Acetate and Sodium Diacetate?
Sodium acetate is a simple salt of acetic acid, while sodium diacetate contains additional acetic acid, providing stronger antimicrobial properties and a vinegar-like flavor.

3. Is Sodium Diacetate safe for consumption?
Yes. Food-grade sodium diacetate (E262(ii)) is approved by both the FDA and EFSA as safe for use in food.

4. What industries use Sodium Diacetate?
It’s used in food (bakery, meat, snacks), pharmaceutical, animal feed, and chemical industries.

5. How is the price of Sodium Diacetate determined?
Pricing varies based on grade, purity, supplier, and market conditions.