Study on optimization of extraction conditions of rosemary essential oil by atmospheric distillation
To explore the optimal extraction process of rosemary essential oil by atmospheric distillation,the experiment was conducted using different distillation times,liquid-solid material ratios,and sampling times for the hydrodistillation of fresh rosemary leaves with reflux extraction by steam distillation.The volatile components were analyzed and compared using headspace injection GC-MS.The extraction process was optimized using the response surface method to determine the best process conditions.All experiments were repeated three times.The results showed that the order of influence of various factors on the yield of rosemary essential oil was liquid-solid material ratio>sampling time>distillation time.The theoretical optimal extraction conditions were determined to be a distillation time of 3.96 hours,a liquid-solid material ratio of 1.50 mL/g,and a sampling time of 13:12,with a theoretical predicted yield of rosemary essential oil of approximately 1.551%.The results showed that the highest yield of rosemary essential oil was 1.543%after sampling time 13:10,liquid-solid ratio 1.50 mL/g and distillation for 4 h,with a relative error of 0.52%compared to the predicted value of 1.551%.The relative content of characteristic components met international standards.The study indicates that the atmospheric distillation extraction process of rosemary essential oil is stable and effective.
rosemary essential oilextraction processatmospheric distillationanalyse of GC-MS