Commonly used solvents in the rubber and plastic industry, the properties and uses of acetic acid

[alias]Acetic acid

[Molecular formula]C2H4O2

[Structural formula]CH3COOH

[Properties]Colorless transparent liquid. It is an important component of vinegar, a typical fatty acid with a pungent sour taste. The relative density of anhydrous is 1.049 (20°C), the boiling point is 118°C, the melting point is 16.604°C, the flash point (open cup) is 57°C, the autoignition temperature is 427°C, and the refractive index is 1.3716 (20°C). Acetic acid is a weak acid, but it can neutralize with alkalis to form acetate; it can also be esterified with alcohols to form various esters. It can be miscible with water, ethanol, ether, glycerin and benzene, but insoluble in carbon disulfide. The pH value of the aqueous solution: 2.4 at 6% and 2.9 at 0.6%. Acetic acid vapor is very easy to catch fire, and the explosion range when mixed with air is 4%-17%. It is non-toxic at low concentrations, and highly corrosive at high concentrations. The content of ordinary acetic acid is about 36%; it has the generality of saturated fatty acids, and it reacts with certain metals, metal oxides and hydroxides to form salts; it undergoes esterification reaction with alcohols.

［Application］ Acetic acid is an important organic chemical raw material. It is used in the synthesis of vinyl acetate, acetate, acetate, thioglycolic acid and chloroacetic acid, etc. It is also used as a solvent for the manufacture of rubber, plastics, dyes, etc. In the printing and dyeing industry, it is used as an anti-alkali agent for dye developing solution, a preparation agent for pigment printing adhesive, as well as a dyeing aid and a dyeing retarder. The food industry is used as a sour agent and spice. In the fermentation industry, it is used as a flavor enhancer for koji wine. It is also a raw material for the manufacture of dyes, medicines, pesticides, and synthetic fibers. It is also used as a disinfectant, fungicide, etc.

[Brief Recipe]

① Acetic acid can be produced by liquid-phase oxidation of acetaldehyde and air or oxygen under the action of manganese acetate and cobalt acetate catalysts.

② Synthesize acetic acid from methanol and carbon monoxide under the action of a catalyst.

③ After butane or naphtha and homogeneous catalyst (manganese acetate, cobalt acetate) are dissolved in acetic acid, acetic acid can also be produced by passing air under high pressure for oxidation reaction.

[Safety and Protection]Acetic acid is a Class II organic acid corrosive substance, hazard code number: 9400l. Packed in aluminum alloy or plastic barrels, the net weight of each barrel is 100kg, 200kg in aluminum barrels, and 25L in plastic barrels. Pay attention to fire and explosion protection during storage.

Low concentration of acetic acid is non-toxic, and when the concentration exceeds 5%, it is highly corrosive to the skin and has a strong irritating effect on the respiratory tract, esophagus, eyes, etc. When touching the skin, it should be washed immediately with plenty of water or 2% baking soda solution.