Calcium acetate

Calcium Acetate is the calcium salt of acetic acid. This compound is typically found in the monohydrate form (Ca(CH₃COO)₂·H₂O), as the anhydrous form is hygroscopic and unstable in high humidity. It has a faint vinegar-like odor or may be odorless. Its good water solubility facilitates its use in various applications.

Molecular Structure of Calcium Acetate

Each molecule of calcium acetate consists of one Ca²⁺ cation and two acetate anions (CH₃COO⁻). It is an ionic compound, and in the solid state, it forms a crystalline ionic lattice that varies depending on the presence of water (monohydrate or anhydrous form).

Key Properties of Calcium Acetate

• Appearance: White crystalline powder

• Odor: Odorless or faint vinegar smell

• Solubility: Highly soluble in water (34 g/100 mL at 0°C), slightly soluble in ethanol, nearly insoluble in acetone

• Molar Mass: 158.17 g/mol (anhydrous), 176.18 g/mol (monohydrate)

• Melting/Decomposition Point: Around 160°C, decomposing into CaCO₃, acetic acid, and water

• pH of Aqueous Solution: For a 5–10% solution in water: approximately 6.3 to 9.5 (depending on concentration and temperature)

• Moisture Absorption: The anhydrous form is slightly hygroscopic but stable when stored in airtight containers

Advantages of Using Calcium Acetate

• Nutritional or Pharmaceutical Calcium Source: Used as a calcium supplement (for osteoporosis and hypocalcemia)

• Food Preservative: Approved as E263, prevents microbial growth

• pH Regulator: Functions as a buffer in food and pharmaceutical products

• Texture Stabilizer: Used in canned vegetables, preserved foods, and tofu

• High Safety: Recognized as safe by FDA and EFSA within regulated doses

• Phosphate Binder: Used in dialysis patients to lower blood phosphate levels

Disadvantages and Considerations

• Hygroscopic Nature: Recommended to be stored in moisture-resistant containers

• Drug Interactions: May interfere with the absorption of thyroid medications, antibiotics, and iron supplements

• Hypercalcemia Risk: Excessive or prolonged use may lead to elevated blood calcium levels

Applications of Calcium Acetate

Food Industry:

• Used as a preservative and buffering agent in bread, cakes, and animal feed

• Stabilizes texture and color in canned fruits and vegetables

• Acts as a coagulant in tofu production

Pharmaceutical and Medical Fields:

• Used as a calcium supplement

• Acts as a phosphate binder in dialysis treatment

• Serves as a buffering agent in pharmaceutical formulations

Textile Industry:

• Used as a mordant in dyeing processes

Chemical Industry:

• Formerly used as a precursor in acetone production (now obsolete)

• In the production of greases and metallic soaps

• Removes sulfate ions from water and wastewater

Other Industrial Applications:

• As a catalyst in specific chemical reactions

• In the production of gel fuels by combining with alcohol