The key difference between steam distillation and fractional distillation is that the steam distillation separates heat sensitive components whereas the fractional distillation separates hydrocarbon fractions.
Distillation is the process of heating a liquid to create vapor that is collected when cooled separately from the original liquid. This process uses the differences in boiling points or volatility of different components in a mixture. There are several types of distillation techniques such as simple distillation , batch distillation, continuous distillation , steam distillation and fractional distillation.
Overview and Key Difference 2. What is Steam Distillation 3. What is Fractional Distillation 4. Steam distillation is a process of separating components in a heat sensitive mixture by adding water to the distillation flask.
Therefore, it is useful as a purification technique to remove impurities in a compound. However, the components of the mixture should be volatile in order to successfully carry this process.
In this process, we separate the components in the mixture by vaporizing them at boiling points lower than their actual boiling point. In this case the system contains two columns and a decanter. The fresh feed A-B is added into the first column In the industry the butanol- water mixture is separated with this technique. Now fresh feed is mixed with entrainer and distilled over. It does not form any type of azeotrope.
Steam distillation remains important in certain industrial sectors. Lab equipment Industrial equipment. Total views 7, On Slideshare 0. From embeds 0. Number of embeds Downloads Shares 0. Comments 0. Likes You just clipped your first slide! Clipping is a handy way to collect important slides you want to go back to later. Now customize the name of a clipboard to store your clips. Visibility Others can see my Clipboard. Cancel Save. In simple distillation, the liquid mixture is heated and the vapor rises through a tube and is collected and recondensed.
The recondensed liquid will have a higher concentration of the more volatile component than the original mix. If the two liquids in the original mix have widely different boiling points, a one-step evaporation and recondensation process is all that is necessary. This process is called simple distillation. Fractional distillation is similar to simple distillation, except the same process is repeated in successive cycles. Each cycle produces a mixture richer in the more volatile compound than the mixture before it.
Fractional distillation is necessary when the boiling points of the liquids in the original mix are close enough to each other that simple distillation is not enough to purify either compound. Some liquids boil at such high temperatures that simple or fractional distillation using the process described above would be impractical or dangerous.
Vacuum distillation, however, offers another alternative. The boiling point of a liquid falls when the pressure is reduced. The boiling point of water, for example, is lower at high altitude than at sea level. By reducing the pressure in the container, the boiling point of the liquids in the mixture can be reduced and the mixture distilled at a lower temperature.
Explain the difference between a bubble point and a dew point. What difference is there between handling zeotropes and azeotropes? Zeotropes must leave the cylinder as a liquid but azeotropes may leave the cylinder as either a liquid or a vapor.
A general definition of refrigerant is: The fluid used in a refrigeration system for transferring heat. The total temperature glide of a refrigerant blend is defined as the temperature difference between the saturated vapor temperature and the saturated liquid temperature at a constant pressure. Many refrigerant blends have temperature glide when they change phase in both the condenser and evaporator.
Azeotropic mixtures have been very widely used in refrigeration, for example the popular cold storage refrigerant R is a mixture of R22 and Ra.
Examples of pure refrigerants are R12, R22 and Ra.
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