The application of formic acid in the printing and dyeing industry, the performance and use of formic acid

[alias] Mosquito acid.

[Molecular formula]CH2O2

[Structural formula]HCOOH

[Property]The simplest fatty acid. It is also known as formic acid because it exists in a small amount in red mosquitoes and in the secretions of some caterpillars. It also exists in the leaves and roots of plants and some fruits. A colorless liquid with a pungent odor. Smoke, flammable relative density 1.220 (20 ℃). Melting point: 8.6 ℃. Boiling point: 100.8°C. The flash point (cup open) is 68.9°C. The spontaneous ignition point is 601°C, the refractive index is 1.3714 (20°C), the viscosity is 1.784mPa·s (20°C), the surface tension is 3.58mN/m (20°C), and the surface tension is 37.58mN/m (20°C). Soluble in water, ethanol, ether, glycerol, slightly soluble in benzene, insoluble in hydrocarbons. Formic acid is the simplest structure among the organic compound aliphatic carboxylic acids (-COOH), and the strongest acidity. Its structure is different from other homologues. The carboxyl groups in formic acid are directly connected, and there is no influence of hydrocarbon chains. It oxidizes easily and is also a good reducing agent. Easily oxidized into water and carbon dioxide, thermally decomposed into water and carbon monoxide with sulfuric acid. Hydrogen gas is released when zinc, magnesium and iron are dissolved in formic acid. Corrosive, causes skin blisters, and is slow to heal. 80%~90% of formic acid is easy to freeze in cold atmosphere.

［Application］Formic acid is a basic organic raw material, which can be used to synthesize formate, formate, formamide and xylamide wait. In the printing and dyeing industry, it is used as a dyeing aid for acid dyes and neutral dyes and as a dyeing aid for nylon dyeing. In the tanning industry, it is used for deliming, dehairing, neutralizing lime, preventing leather mildew and making the leather surface clean and smooth. In the pharmaceutical industry, it is used to produce borneol, analgin, aminopyrine, caffeine, vitamins and other drugs. In the pesticide industry, it is used to produce insecticidal glands, green fodder and grain preservation. It can also be used as rubber coagulant, cement coagulant, disinfectant, preservative, fiber and paper dyeing agent, plasticizer, pH regulator, animal feed additive, and used in the manufacture of oxalic acid and various solvents.

[Brief recipe]

①Sodium formate is obtained by reacting carbon monoxide and sodium hydroxide at high temperature, and formic acid is obtained by acidifying sodium formate with sulfuric acid.

②Formic acid can also be produced by oxidation of methanol or formaldehyde under certain conditions.

［Safety and Protection］Formic acid is a first-class organic acid corrosive substance, hazard code number: 92001. Packed in plastic barrels, each barrel Net weight 25kg. Do not coexist with ammonia, sulfuric acid or oxidizing agents. There should be signs of “corrosive substances” and “poisonous substances” on the packaging. Store in a cool, ventilated and dry place. Formic acid is a flammable liquid with an explosion limit of 18% -57%.

Formic acid is soluble in fat and can be absorbed through the skin. The steam is strongly irritating to the eyes, and the irritation to the mucous membrane is similar to that of inorganic strong acids. If the skin comes into contact with formic acid, it should be washed immediately with plenty of water, or with a 2% baking soda solution.