The short path distillation is more and more well-received in many fields. Compared to other separation methods, such as extraction, filtration and crystallization, it has the advantage that no other solvents than system components are required, thus ensuring that no new impurities are introduced. So what is a short path distillation? Let’s talk about it in the following.
What is a Short Path Distillation?
The short path distillation refers to a kind of evaporation and distillation equipment. As a type of thermodynamic separation technology, the equipment can evaporate components with low boiling points by utilizing that the boiling point of each component in the mixed liquid or liquid-solid mixture is different, and then condense the material to separate the whole components. It is the combination of evaporation and condensation unit operations as well as a kind of liquid-liquid separation technology.
The principle is that the pressure difference between the boiling film and condensing surface is the driving force of the steam flow, and the minimum pressure will cause the flowing of steam. Under the 1mbar, the operation requires that there is the shortest distance between the boiling surface and condensing surface. The evaporator manufactured based on the principle is called the short-path distillation. The short-path distillation (molecular distillation) is equipped with a inside condenser which is opposite to the heating surface, and make the operation pressure reduce to under 0.001mbar. Its relative low boiling temperature is very suitable for the material with heat sensitive and high boiling point.
Components of Short-Path Distillation
1. Evaporation equipment
Evaporation equipment is the key part of the whole equipment. It is in charge of evaporating solvents, which is to extract solvents from liquid sample. In this part, there are two parts, which are heating mantle and evaporation flask. Heating mantle is to improve the evaporation flask’s temperature till solvents’ boiling point in order to extract it. The temperature of heating mantle is adjustable and users can adjust temperature through control panel.
2. Receiving equipment
There are two different receiving flasks here in the whole equipment. Because short path distillation is to separate two solvents, then it is necessary to set two different containers.
3. Condensing equipment
Liquid solvents are easier than gas solvents to collect. So there is condensing equipment working here to cool the gas solvents down. In this part, low temperature coolant circulation pump and condenser work together to cool gas solvents down.
4. Vacuum pump
In the whole process, the equipment works under vacuum at the whole time. Vacuum pump provides vacuum environment for the reacting equipment.
What does Short Path Distillation Do?
The short path distillation is one of the most high-efficiency distillation techniques in people’s using, which can solve the problem that conventional distillation technology can’t. It is widely used in food, medicine, fine chemicals, electronic materials, plastic engineering and polymers (such as polyols, fatty acids, polyphenols, polyurethane, epoxy resins, lactic acid, monoglycerides, flavors, heavy oils and paraffin oils) and other fields.
Advantages of Short Path Distillation
The short path distillation is widely used in industrial field because it has many advantages, as following:
- Because of vacuum environment, the boiling point of solvents will become lower properly. Then we do not have to offer that energy to heat the sample mixtures, which means more energy can be saved in the short path distillation’s working process.
- The short path distillation can offer a higher purity of extracted solvents than the traditional extracting apparatus. In the whole working process of the short path distillation, the pressure difference between vacuum and atmospheric pressure keeps the whole equipment sealed tightly, which makes the purity of extracted solvents high.
- Meanwhile, the size of short path distillation is smaller and more economic than the traditional extracting apparatus, which saves more material and energy.