To the reactor equipped with stirring, thermometer and overhead tank, add formic acid and hydrogen peroxide, start stirring, then add 1-octene, after the addition, the reaction mixture solution is kept for 100 minutes, and then the formic acid and the formic acid are evaporated under reduced pressure. Water, then add sodium hydroxide solution under stirring until the pH value of the mixture solution is alkaline, then add ester to extract, the obtained extract is washed twice with sodium chloride with a concentration of 30%, and the washed extract is added without After dehydration of magnesium sulfate water, vacuum distillation is performed, and fractions are collected under the condition of 131°C/1330Pa, and the obtained fractions are the product 1,2-octanediol. The reaction temperature in the reactor is controlled at 20-90°C.
In a four-necked flask, install an electric stirrer, a condenser, a thermometer, an external cold water bath, and a dropping funnel. Add metered formic acid, hydrogen peroxide and catalyst to the flask in turn, and stir vigorously to mix thoroughly. Under external cooling, add a metered amount of 1-octene dropwise, control the temperature in the bottle to react at 35°C-40°C, after the dropwise addition, keep the reaction at 40°C-45°C for 3-4 hours, and then stir at room temperature After 1-2 hours of reaction, a clear and transparent mixed solution can be obtained. The clear and transparent mixed solution was distilled under high vacuum and reduced pressure, and the water and excess formic acid were distilled off until only an oily substance remained.
2. Neutralization and extraction
In a four-necked flask, configure an electric stirrer, a thermometer, a cold water bath, a condenser, and a dropping funnel. Put the above-mentioned oily substance into the flask, turn on the stirrer, control the temperature in the flask at 40℃-45℃, add 30% NaOH solution dropwise for neutralization, and add enough NaOH solution to make the pH value of the solution rise to 12 -13. After the pH value is stable, sample and analyze, and after passing the test, neutralize the obtained mixed solution with 30% HCl at 20 °C to make the pH value of the mixed solution 7, and the neutralization time is about 3h. Add solid NaCl to the mixed solution to make the aqueous phase a saturated brine mixture. Then add an appropriate amount of ethyl acetate for extraction, and the extract is saturated with
Washed with brine, finally dried over anhydrous Na2SO4 and vacuum filtered.
The filtrate was concentrated under reduced pressure, and the ethyl acetate was evaporated until only oil remained; then the oil was distilled under reduced pressure at 1.33*103Pa, and the product was evaporated, which was a colorless, transparent liquid with a pungent odor. It was analyzed by gas chromatograph FID-6890 area normalization method, and the content was more than 99%.