Synthetic method of diphenyl sulfide

Abstract

The invention discloses a synthesis method of diphenyl sulfide. According to the method, the molar ratio of benzene, Lewis acid catalyst and sulfur is 3.0~3.6:1.0~3.0:1.0. After mixing benzene and catalyst, the temperature is raised to 50~70°C, sulfur is slowly added, and the hydrogen sulfide gas generated by the reaction is Pour into the sodium hydroxide solution, reflux until the reaction is complete after adding the sulfur, then cool to room temperature, and slowly add the synthetic material dropwise to 5-15% dilute hydrochloric acid for pickling, leave the upper layer organic layer after stratification Benzene is removed by heating and precipitating to obtain diphenyl sulfide, and benzene is recovered and used mechanically. The invention uses benzene and sulfur as raw materials, significantly reduces the cost, produces less waste gas and waste water, is environmentally friendly, and reaches the international standard. More than 98%, suitable for industrial production.

Description

technical field [0001] The invention relates to a synthesis method of diphenyl sulfide, which belongs to the field of organic chemistry. Background technique [0002] Diphenyl sulfide is an intermediate of pesticides, medicines, and dyes, and it is also used for the synthesis of 2,4-dichlorophenol, pesticide herbicides (benben, 2,4-D), insecticide ibifos (EPBP), and veterinary drug Dukesan And other catalysts can also be used in the synthesis of sulfur bis-dichlorophenol and so on. [0003] At present, there are mainly four preparation methods of diphenyl sulfide: 1) first mix benzene and aluminum trichloride, cool to a certain temperature, add dropwise the mixed solution of sulfur chloride and benzene under stirring, and hydrogen chloride will escape at the beginning of the reaction and a small amount of hydrogen sulfide to precipitate a yellow viscous aluminum trichloride complex. After the reaction is complete, diphenyl sulfide is obtained through a series of post-treatm...

AI Technical Summary

Problems solved by technology

[0004] The disadvantage of the first two methods is that sulfur chloride is a golden yellow liquid, and when the purity is not high, it is often caused by the presence of SCl 2 It is orange or even slightly red, fumes in humid air, and has an unpleasant pungent smell. The treatment of the three wastes is very difficult, and the yield is too low

The raw material iodobenzene of the third method is more expensive, and the yield is too poor, the production cost is relatively large, and it is difficult to form a production capacity

The fourth method needs to be carried out under high pressure. Although the yield is higher than that of the first three methods, it has higher requirements on the reaction conditions, and there are more operation steps and larger investment.

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