Physicochemical properties and preparation method of sodium pentachlorophenate

Sodium Pentachlorophenate

[Alias] Sodium Pentachlorophenol

[Structural formula]

[Physical and chemical properties] White or light yellow needle-like crystals

[Preparation]

(1) Preparation method

①Hexachlorobenzene route method The traditional preparation of sodium pentachlorophenate adopts a three-step method, that is, the synthetic route of "useless substance → trichlorobenzene → hexachlorobenzene → sodium pentachlorophenate"

The above reaction does not use methanol as a solvent, and the reaction temperature and pressure are slightly higher than the methanol solvent hydrolysis method

Figure 7-11 Process flow of hexachlorobenzene route method

②Phenol direct chlorination method This method is a method for preparing sodium pentachlorophenate proposed in patent CN1923777, which adopts the two-step method "phenol→pentachlorophenol→sodium pentachlorophenol"

Figure 7-12 Process flow of phenol direct chlorination method

(2) Preparation example

①Put 1000kg of petroleum phenol into the chlorination reaction kettle, and pass steam into the jacket of the chlorination reaction kettle, and when the temperature in the kettle rises rapidly to 80°C, pure aluminum is added as a catalyst at a ratio of 1%, and then chlorine gas is added.

②Put the flake caustic soda into the alkalization tank and divide it into 3 times at a temperature of 80°C, with 10 min intervals each time, add pentachlorophenol, control the temperature at 90～95°C after feeding, and control the steam pressure after 2h alkalization At about 0.

[Technical Index] HG2-347-76

[Application] Sodium pentachlorophenate is mainly used as herbicide, bactericide, preservative, antifungal agent, etc.

Sodium pentachlorophenate is a contact herbicide, which mainly controls the germination of barnyardgrass and other seeds

Related link: Dichlorophen bactericidal and algaecide