Rotary Evaporator Suppliers Tell Us How to Buy Rotovap

The first step is to choose the specifications of the rotary distiller

The specifications of the rotary distiller are distinguished by the volume of the evaporating flask. The size of the evaporating flask depends on the amount of evaporated material.

Generally speaking, 2L, 3L, 5L rotary distillers are suitable for small-scale laboratory experiments; 5L, 10L, 20L rotary distillers are suitable for pilot tests; 20L, 50L rotary distillers are suitable for pilot tests and production. If you want to buy rotovap, you should first know the capacity you need.

The second step considers the evaporation rate of the rotary distiller

For the rotary distiller of the same specification, the evaporation rate of the rotary distiller is also important to buy rotovap. There are four main factors that affect the evaporation rate.

1. Heating tank temperature

The higher the heating bath temperature, the stronger the evaporation of materials. However, the commonly used temperature is 60 degrees Celsius, which is limited by material heat resistance, safety, and energy consumption. The temperature of the heating tank minus the heat transfer temperature difference of the evaporating flask T1 and the evaporation superheat is the material temperature. The heat resistance of materials mainly refers to the permissible temperature at which biologically active substances do not change.

Safety in use mainly refers to the risk of no scalding during the process of changing the evaporating flask. The temperature of the heating bath is moderate, the water volatilization rate is low, and the energy utilization rate is high.

2. Condenser coolant temperature

Material temperature minus condenser t2 heat transfer temperature difference and condensation subcooling, that is, the average temperature of condenser coolant required, and the relationship between material temperature and vacuum is in line with the saturation temperature and pressure of the material relationship. When determining the temperature and vacuum of the heating tank, the temperature of the cooling medium depends on the type of material.

3.Evaporating flask speed

The higher the evaporating flask speed, the larger the infiltration area of the inner surface of the flask and the larger the heating area; but at the same time, the thicker the liquid film thickness, the greater the heat transfer temperature difference.

For materials of different viscosities, there are rotational speeds. As the temperature, vacuum degree, and cooling medium of the heating tank are related parameters, these parameters are related to the material type and condensate recovery rate. If you need the help of our technicians, please fill in the “User Demand Form”.

4. Rotary distiller vacuum

95-98 kPa (pressure 2-5 kPa) is recommended.

The third step is to choose supporting equipment.

The supporting equipment refers to vacuum equipment and cold source equipment.

The vacuum pump is recommended to use a water circulation vacuum pump or diaphragm vacuum pump, which is resistant to corrosion by various solvents. A vacuum controller for rotary evaporator can be selected to achieve a more controllable distillation process. Rotary evaporator suppliers also supply these types of vacuum pumps for you to choose from.

Choose cold source equipment according to cooling medium temperature and evaporation

The basic working conditions of the rotary distiller are as follows: heating bath temperature 60°C, vacuum degree 95-98 kPa (pressure 2-5 kPa), cooling medium temperature 20°C.

The working parameters are as follows: heating tank temperature<80℃, vacuum degree<98kPa (pressure<2kPa), cooling medium temperature -20℃, and room temperature.

As professional rotary evaporator suppliers, Hawach recommends that we first determine the type of condenser that needs to be used. There are two types of condensers for rotary distillers: vertical and inclined. There is no difference in heat transfer and flow processes between them. Because the vertical evaporator occupies a small area, the rotary distiller usually adopts a vertical condenser.