Acetic acid chemical formula CH3COOH pure anhydrous acetic acid
Chemical formula: CH3COOH
Appearance: Colorless transparent liquid with pungent odor
Particular weight: 60.05
CAS: 64-19-7
EINECS: 231-791-2
Melting point: 16.6 ℃
Boiling point: 117.9 ℃
Water soluble: Dissolved in water
Density: 1.05 g/cm³
Flash point: 39 ℃
UN No.: 2790
Physical properties:
Boiling point: 117.9℃
Freezing point: 16.6℃
Relative density (water=1): 1.050
Chemical properties
Acidity of acetic acid
The carboxyl hydrogen atoms of acetic acid can be partially ionized into hydrogen ions (protons) and released,acidity leading to carboxylic acid.Acetic acid is a weak monobasic acid in aqueous solution with an acidity coefficient of 4.8.pKa=4.75(25℃).A solution of acetic acid with a concentration of 1 mol/L (similar to the concentration of household vinegar) has a pH of 2.4.That is to say, only 0.4% of the acetic acid molecules are dissociated.
The following is the national standard of the People’s Republic of China on industrial acetic acid:
Item |
Specific |
||
Grade |
Premium |
First grade |
Qualified |
Chroma,Hazen Units (Platinum-Cobalt) ≤ |
10 |
20 |
30 |
Acetic acid content % ≥ |
99.8 |
99.0 |
98.0 |
Moisture % ≤ |
0.15 |
- |
- |
Formic acid content % ≤ |
0.06 |
0.15 |
0.35 |
Acetaldehyde content % ≤ |
0.05 |
0.05 |
0.10 |
Evaporation residue % ≤ |
0.01 |
0.02 |
0.03 |
Iron content (as Fe)% ≤ |
0.00004 |
0.0002 |
0.0004 |
Reduction of potassium permanganate substances min ≥ |
30 |
5 |
- |
Application
Industry application
- Acetic acid is a bulk chemical product and one of the most important organic acids.Mainly used in the production of acetic anhydride, acetate and cellulose acetate, etc.Polyvinyl acetate can be made into films and adhesives and is also a raw material for synthetic fiber vinylon.Cellulose acetate can be used to make rayon and motion picture film.
- Acetates formed from lower alcohols are excellent solvents and are widely used in the paint industry.Since acetic acid dissolves most organics, it is also a commonly used organic solvent (eg for the oxidation of p-xylene to produce terephthalic acid).
Storage management
Store in a cool, ventilated warehouse. Keep away from fire and heat sources. In the freezing season, the storage temperature should be kept higher than 16 ℃ to prevent solidification.Keep container tightly closed. It should be stored separately from oxidants and alkalis, and should not be mixed.Use explosion-proof lighting and ventilation facilities. Prohibit the use of mechanical equipment and tools that are prone to sparks. Storage areas should be equipped with emergency release equipment and suitable containment materials.