Abstract��
Nerol and geraniol are important fragrant additives widely used in many areas.Both of them are temperature sensitive materials and the difference of the boiling point between them is 2�� only.Vacuum batch distillation may be preferable for processing temperature-sensitive materials.In the previous study on the purification of nerol and geraniol by vacuum batch distillation,the temperature of still pot was high,the period of experiment was too long and yield was small(46%) though distillate of nerol's purity above 90% were gained.Distillation at lower pressure results in lower temperature of still pot and higher relative volatility,and operation for a constant product of composition at the column top is mostly applied to separate batches of binaries.In this paper,the effects of operational conditions such as time of total reflux,reflux ratio pressure on the purity of nerol and geraniol are investigated.This research chooses following experimental conditions of distillation:600 to 700Pa operational pressure,temperature of still pot at about 152��,top temperature at about 80��,5.5h to 6h time of total reflux,reflux radio varying from 20/1 to 5/1,and (4 800) to (4 900)Pa pressure drop of column.By one-pass distillation operation under the condition described above,nerol and geraniol were gained with yield up to 65% and purity above 90%.The experimental results provided an important basis for technique innovation in factories,for the total cycle time is adoptable and the process is steady without thermal decomposition.
HANG Jin-yu,ZHANG Hai-ying,CHANG He-ying,WANG Hua.Study on the Purification of Nerol and Geraniol by Vacuum Batch Distillation[J]. Chemcial Industry and Engineering, 2003,20(6): 429-433
2003, Vol. 20 
