Ethylene Glycol → Tetrachlorophthalic acid

Participants

Reaction Steps

A 20 g quantity of sodium hydroxide was dissolved in 1000 g of water, and 200 g of ethylene glycol was added to the solution. Subsequently, 143 g of tetrachlorophthalic anhydride was added to the mixture, and the resulting mixture was heated to 95° to 98° C. to obtain a solution. A 122.5 g quantity of 40% aqueous solution of Cr2 (SO4)3 was diluted with 200 g of water and then added dropwise to the obtained solution at the same temperature, over a period of 40 minutes. The resulting mixture was thereafter stirred for 20 minutes, and provided a grayish green precipitate. Subsequently, 10% aqueous solution of sodium hydroxide was added dropwise to the reaction mixture to adjust the pH thereof to about 3. About 13 g of sodium hydroxide was so used. The mixture was further stirred for 2 hours, then cooled and filtered at about 50° C. The resulting reaction product was washed with water and dried, giving 140 g of Cr complex compound of tetrachlorophthalic acid. This complex compound was found to have good thermal stability (as tested at temperatures of below 350° C. in the same manner as described in Example 1).

Provenance & Evidence