反应详情

温度

80 °C

Three hundred grams of parahydroxybenzoic acid and one thousand and five hundred grams of 10% aqueous methanol solution were put into a 2 L flask, and heated to 80° C. to give a 10% aqueous methanol solution containing parahydroxybenzoic acid. The solution was cooled to 25° C. at a rate of 0.5° C./min, and filtered by using a centrifuge at 25° C. As a result, 324.9 g of crystalline parahydroxybenzoic acid monohydrate was obtained. The water content measured by Karl Fischer's method was 16.6%. The resulting crystalline product was dried with airflow at 70° C., and 268.4 g of crystalline parahydroxybenzoic acid anhydride was obtained.

1. temperatureThe solution was cooled to 25° C. at a rate of 0.5° C./min
2. filtrationfiltered
3. customat 25° C