Study On Batch Distillation Of Heat Sensitive Material In A Batch Stripper

The research of the distillation of heat-sensitive material was briefly reviewed in this paper. The studies on inverted batch distillation were introduced, and the main difficulties of such a process in application were also pointed out..In order to study the process of inverted batch distillation for separating heat-sensitive material, a constant volume hold-up batch distillation model with heat sensitive reaction was established and solved by Gear method. The characteristics of inverted batch distillation process was investigated and the effects of operation parameters such as reboiler ratio, reaction rate, theoretical stages and feed composition to inverted batch distillation were also studied by simulation. The simulation results show that: For the separation of heat sensitive material in a batch stripper, it is benefit to the separation of the heat sensitive material if the reboiler ratio is increased properly, but the reboiler ratio cannot be very large, otherwise, the heat damage ratio is increased and the purity and yield of the heat sensitive material are decreased, so the reboiler ratio has an optimum value; Generally, it is benefit to the separation of heat sensitive material if the number of the theoretical stages is increased, but the number of theoretical stages cannot be very large for the high vacuum distillation; It is difficult to separate the heat sensitive material with a large heat sensitive reaction rate. Furthermore, the comparison between the inverted batch distillation and the conventional batch distillation was carried out. It shows that: the inverted batch distillation is more suitable for the separation of heat sensitive material, especially for the feed containing a large amount of heat sensitive heavy component.The batch distillation experiments for separation of methanol,ethanol,N-propanol were carried out, and the simulation results agrees with that of experiments. The heat sensitive test of 4-methyl-3-decen-5-ol was carried out and effects of temperature and pressure were studied. The separation experiments of 4-methyl-3-decen-5-ol and methyl anthranilate in batch stripper were carried out, and the experiment results proved the effectiveness of inverted batch distillation for heat sensitive material separation.