How to further improve the molecular distillation equipment？

    Molecular distillation is a distillation process operating under high vacuum, where the mean free path of the vapor molecules is greater than the distance between the evaporation surface and the condensing surface, so that the difference in evaporation rate of the components in the feed liquid can be utilized. Separate.
    Although molecular distillation equipment has become more sophisticated, there are still many shortcomings in actual operation. For better operation, the molecular distiller can be modified as follows.
(1) In the feeding system, in order to ensure the high vacuum of the system, the materials to be separated should be degassed first, and the large-scale industrial production should be separately provided with a vacuum degassing system. The liquid storage tank should be provided with a heating and stirring device so that the liquid can be preheated in the storage tank before the feed liquid is sent to the distiller to increase the distillation efficiency. In the molecular distillation process, the feed rate is a very important operating parameter, so accurate flow measurement and control instruments should be installed on the feed line.
(2) Distillator, the retort is always in a high vacuum state during operation. In the study of mass transfer and heat transfer of molecular distillation, temperature and pressure distribution data inside the distiller are very needed, and the current common molecular distillation device Only the temperature of the heating medium on the evaporation surface and the pressure at the vacuum pump interface can be measured. Therefore, for small molecular distillation equipment mainly used in experimental research, if temperature and pressure detection probes can be set at appropriate positions in the distiller to obtain temperature and pressure distribution data between the evaporation surface and the condensation surface, the pair of molecular distillation The research of the process and the development of new molecular distillation equipment are of great significance.
(3) The fraction collection system, the fraction may be in a solid state at normal temperature, so the fraction collection system should be provided with a heat preservation or heating device to prevent the distillate or the residual liquid from being cooled to a solid and clogging the pipeline during the outflow process. For small molecular distillation equipment mainly used in experimental research, the structure of the receiver should adopt a multi-stage receiving form, so that the fractions under different operating conditions can be collected without stopping by adjusting the valve or the turntable, thereby giving experimental research bands. Convenient.
(4) Cooling system, the constant temperature water bath that controls the temperature of the cooling system should have both heating and cooling functions. If there is only heating function, if the temperature is high and the distillation temperature is low, the condensation effect may be too small due to the temperature difference being too small, resulting in a decrease in yield, and in severe cases, the condensation temperature may be unstable, causing measurement error. Increased, resulting in non-parallel results.