Phthalimide is a white prismatic crystal. Phthalimide is soluble in alkali solution and boiling acetic acid, slightly soluble in water and ethanol and soluble in benzene. Can sublimate. It is mainly used for synthesizing intermediates of various fine chemicals, producing ion exchange resins and surfactants, etc. The pure product is white crisp crystal, and the industrial product is light yellow amorphous block, which is soluble in alkali and glacial acetic acid at 238℃, insoluble in water and slightly soluble in heated chloroform, benzene, ether and alcohol.
High quality phthalimides have the following uses:
① Phthalimide is the intermediate of germicide chlordane, insecticide thiophosphate and herbicide bentazone.
② It can be used to produce CTP as pesticide, dye, perfume, medicine and rubber auxiliary agent, and also can be used to produce high-efficiency ion exchange resin and surfactant, etc.
③ used for organic synthesis
④ This product is an intermediate of many fine chemicals, such as auxiliary dyes, pesticides, medicines, rubber additives, etc., for example, it is used to produce phthalide, phthalonitrile, indigo, germicide, germicide, insecticide, and so on.
The following dioxane manufacturers introduce the preparation method for everyone:
Its preparation methods include ammonium bicarbonate method and urea method in industrial production. There are many methods to prepare phthalimide from phthalic anhydride, among which ammonium bicarbonate method and urea method are actually used in industrial production.
(1) ammonium bicarbonate method
In ammonium bicarbonate method, phthalic anhydride and ammonium bicarbonate are mixed according to the molar ratio of 1: 1.2, crushed by a pulverizer, put into a reaction kettle, heated for about 4 hours to 200℃, and then heated to 280-300℃ at a slightly faster rate. The melt is discharged to crystallization, cooled, solidified and crushed to obtain the finished product with a yield of over 95%.
1030kg phthalic anhydride and 660kg 95% ammonium bicarbonate are consumed per ton of phthalimide with 95% content. (Phthalic anhydride and ammonium bicarbonate (liquid ammonia or ammonia water) are evenly mixed according to the molar ratio of 1: 1.2, heated at 300℃ in a reaction tank, cooled and crushed to obtain the finished product. )
(2) Urea method
In urea method, phthalic anhydride and urea are mixed evenly, heated and stirred, and when they are completely melted and kept at 160℃ for about 10min, the volume of reactants suddenly increases, and the heating is stopped and stirred until the reactants are solidified, then heated with large fire, and then stopped for several minutes and stirred continuously. After a certain time, water is added to filter, washed with 3% sodium bicarbonate first, then washed with water and dried to obtain the finished product.