Nowadays, a rotary evaporator is mainly applicable for the concentration, crystallization, drying, separation and solvent recovery widely used in pharmaceutical, chemical and biological fields, factories and laboratories. Some people may wonder how to choose an appropriate rotary evaporator and what should be taken into consideration. The following could be helpful for purchasing an appropriate rotary evaporator.
Before purchasing a rotary evaporator, there are four things that should be given consideration to:
- What is the distillation amount of a rotary evaporator?
- What is the expected distilled solvent?
- What is the boiling point of the solvent?
- What is the number of samples to be distilled？
Once you’ve determined the experimental requirements for distillation and the type of solvent, you can start buying rotary evaporators. Besides, in the process of purchasing, we should also pay attention to four issues.
Tips on Purchasing a Rotary Evaporator:
- Develop a clear rotary evaporator specification. The specification of rotary evaporators is determined by the value of the flask.The size of the evaporator depends on the number of materials. In general, 2L, 3L, 5L rotary evaporators are suitable for small laboratory tests; 5L, 10L and 20L are suitable for medium test; and 5L, 10L, 20L are suitable for medium scale test and production.
- Specify the number of distillation flasks required by a rotary evaporator. The distillation efficiency is critical, which determines the number of samples that need to be steamed in a single day. Under the same conditions, the higher efficient the distillation is, the more samples can be distilled. Here, I want to explain again some factors that affect the efficiency of distillation, such as the vacuum degree in the system, the temperature of the heating pot, and the temperature of the cooling medium.
- It is necessary to assess the security risks that exist.The main risks of distillation mainly come from the distillation solvent and heating medium. If the heating medium is silicone oil, the ignition temperature is 25 ° C higher than the heating plate temperature. Distillation solvents with flammable, explosive, explosion-proof glass components are preferred. After the distillation is complete, it is correct to choose automatic deflation so as to avoid manual deflation that may cause an explosion. If you need to optimize the laboratory, the auxiliary condensing unit can maximize the recovery of the distillation solvent, which is also an excellent choice.
- Pay attention to the after-sale service. After-sales service is an important reference standard when purchasing a rotary evaporator. With the development of science and technology, the products made in China are highly competitive in the market and have attracted wide attention. At the same time, the products made in China have favorable price and quality guarantee.
What’s the Core Technology of Rotary Evaporator?
The key is system’s air tightness, that is whether system can keep high vacuum degree under all sorts of solvent’s corrosion and movement state. Henan Lanphan’ s R series instrument, which is sealed by composite material four fluorine rubber and glass, can stand all sorts of solvent, has reliable gas tightness and can maintain a high vacuum degree above -0.096MPa.
Electric Lift or Manual lift, Which One is Better?
Electric lifting like icing on the cake. But some cases with explosion-proof requirements almost do not consider electric lifting. Considering the cost performance, safety, failure rate and other factors, more customers buy manual lifting rotary evaporators.
How to Choose a Matching Vacuum Pump for Rotary Evaporator?
The vacuum pump is one of the necessary supporting products of rotary evaporators, users can choose according to the actual situation. Generally speaking, desk top vacuum pump is one of the hot products for its light weight, anti-corrosion, pollution free as well as low cost, and it is suitable for rotary evaporators whose volume is under 5L. More than 5L rotary evaporators use vertical vacuum pumps, which also features pollution free, corrosion resistance and larger pumping capacity. The working medium of rotary vane vacuum pump is oil, with high speed, large pumping capacity, which can be used alone or as a pre-stage pump and pre-pump for various high vacuum systems. The diaphragm vacuum pump is small in size, light in weight, and powerful in pumping work, but it is higher in cost than the above. Does the power of the bath pan affect the evaporation rate? The power of the water bath greatly affects the evaporation speed. In particular, when vaporizing a substance with a large latent heat such as water, gasification absorbs a large amount of heat energy, and its fastest evaporation rate is almost proportional to the maximum heating power.
What if the Temperature of Water is not Low Enough to Condense?
In summer, the tap water temperature is close to 30 ° C, and the solvent with a steam temperature of 30 ° C or less is almost impossible to recover. At this point we can use the following methods:
- Choose a low temperature circulating water pump. Note that the refrigerating capacity is more important than the minimum temperature.
- Small rotary evaporator below 5L can be equipped with cold traps for ice cooling, which costs less but requires ice to be applied by hand.
- Reduce the vacuum degree and improve the steam temperature,At the expense of evaporation rate, the temperature of the bath is constant.
What Factor Decides the Working Efficiency of Rotary Evaporator?
For same type equipment, mainly includes: steam temperature, vacuum degree and cooling water temperature. Restricted by some material’s thermolability, the steam temperature may have certain limitation when working, so high vacuum degree and low cooling water temperature are two main factors for efficiency improving (can select cryopump to lower the temperature).