Ethyl (R)-3-hydroxybutyrate (88.4 g) and water (300 ml) were added to a three-vial bottle. Potassium hydroxide (37.5g) was slowly added in batches within 3 hours and the temperature is 10 °C. After 2 hours, add activated carbon (0.3g ) to the mixtrue. Continue the reaction for 10 minutes and then filter the reaction solution. The filtrate was concentrated to 100 ml. Stir for 1h to room temperature. After centrifugation and vacuum drying, white solid (potassium 3-hydroxybutyrate) was obtained. Yield=88.2%.
