Formaldehyde is an organic chemical with the chemical formula HCHO or CH? O. also known as ant aldehyde. It is a colorless and irritating gas, which is irritating to human eyes and nose. The relative density of gas is 1.067 (air = 1). Melting point -92℃, boiling point-65438 09.5℃. Soluble in water and ethanol. The highest concentration of aqueous solution can reach 55%, usually 35%-40%, usually 37%, which is called formaldehyde water, commonly known as formalin.

The chemical properties of formaldehyde redox are very active. Under the catalysis of metal or metal oxide, it is easily reduced to methanol; When oxidized, formic acid or carbon dioxide and water are produced. Formaldehyde is a strong reducing agent, which is more reducing when it is weakly alkaline, and can be slowly oxidized into formic acid in air.

Condensation reaction formaldehyde itself can undergo condensation reaction. Add 10%- 12% methanol as polymerization inhibitor in general commodities, otherwise polymerization will occur. It can perform aldol condensation reaction with aldehydes and ketones. It is easy to condense with ammonia or amine compounds, for example, it reacts with ammonia to produce urotropine, and condenses with urea to produce dimethylol urea. Ethylene glycol can be produced by condensation of formaldehyde with synthesis gas.