0
Under what basic principle is fractional distillation employed in separating mixtures.?
Wiki User
∙ 8y ago
Fractional distillation is based on the principle that every liquid has a different boiling point. None of the mixtures of two or more miscible liquid have the same boiling point in the universe. So a mixture of two miscible liquids will have different boiling points and on the basis of this difference, the components of the mixture can be separated by the fractional distillation.
Fractional distillation is accomplished by applying varying degrees of heat (or cooling, depending on how you investigate it) to the process of separating different substances. Fractional distillation is applied broadly in the petrochemical industry to recover hydrocarbons of differing boiling points. In brief, if we heat a mixture of hydrocarbons sufficiently, all of those that have boiling points lower than the setting will evaporate or boil off of the inflow to the unit. As vapor or gas they rise. And as the temperature is reduced in stages as we move higher up the structure or tower (which some call a cracking unit), those substances with boiling points higher will begin to condense out. More volatile substances will continue higher in the unit before cooling is sufficient to get them to condense, and this will permit substances of even greater volatility to rise further before being condensed and recovered. It should be noted that in petrochemical refining, the chemist (petrochemist) is a key player, and nothing proceeds without him or her. But fractional distillation is a physical process, and not a chemical one. Links can be found below to check facts and learn more.
Wiki User
∙ 8y ago
Wiki User
∙ 7y agoDistillation is based on the differences between boiling points of components.
Wiki User
∙ 7y agoDistillation is applied to mixtures of liquids.
Wiki User
∙ 7y agoFractional distillation method of separation is based upon differences between boiling points of components.
Add your answer:
Earn +20 pts
What is the difference between extractive distillation and azeotropic distillation?
Extractive and azeotropic distillation have the common feature that a substance not normally present in the mixture to be separated is deliberately introduced into the system in order to increase the difference in volatility of the most hard to separate components. Extractive distillation can be defined as distillation in the presence of a substance which is relatively non-volatile compared to the components to be separa- ted, and which, therefore, is charged continuously near the top of the fractionating tower, so that an appreciable concentration is maintained on all plates in the tower below its entry. Azeotropic distillation can be defined as distillation in which the add- ed substance forms an azeotrope with one or more of the components in the feed, and by virtue of this are present on most of the plates in the tower above its entry at an These separation methods find their principal applications in the separation of mixtures whose components boil too close together for the economical use of simple fractionating equipment. These separation methods are particularly applicable when the components to be separated differ in chemical type. The theoretical principles in- volved are well documented, and will not be further considered here. The processes differ in the means used to maintain be desired solvent concentration on the plates of the tower. In extractive distillation the high concentration of solvent is maintained by virtue of its non-volatility, and by the fact that it is charged at a high point in the tower. The solvent is, necessarily, removed from the base of the principal tower. In azeotropic distillation, most of the solvent is taken off from overhead, with rela- tively small amounts (ideally, none) drawn off with the bottoms. Extractive distillation is generally more flexible than azeotropic distillation, a greater variety of solvents and a wider range of operation conditions are available; and the concentration of solvent may be controlled by heat and material balances rather than by the accident of azeotrope composition. Furthermore, since vaporization of the solvent is not required beat loads are usually considerably less. It has been mainly used for the separation of toluene, not benzene. But it is mentioned here for the sake of completeness. The use of azeotroptc distillation as a means of separation of BTX components from other non-aromatic hydrocarbons has been known and employed for some thirty years. Acetone is used as an entrainer to purify benzene from similar-boiling non-aro- matic hydrocarbons. Toluene can be separated by the use of either methanol, or of methyl ethyl ketone. Ethyl benzene may be separated from styrene either by isobuta- nol, of by l-nitro-propane. In a 1966 review paper, further information was made available. Fifty-eight pos- sible entraining agents for separating ethyl benzene (bp. 136.20C) and para-xylene (bp. 138.40C) have been examined. It would appear that 2-methyl butanol is the most suceessful agent, requiring a column with only 48 percent of the number of the- oretical plates required if no entrainet were used. The separation of para-and meta-xylenes (bp. 138. 20C and 139. 2aC respectively ) is much more difficult. Of thirty five entrainers examined the best appears to be 2-met- bylbutanol, but the change of relative volatility is only from l. 020 t0 1. 029, and hence it can be safely concluded that azeotropic distillation for the separation of the para-and meta-xylenes is not an economic proposition. Last, and easiest of the C8 aromatics is the separation of meta-from ortho-xylene ( bp. 139. 20C and 144. 50C respectively ). Twenty-eight entrainers were examined, the best being formic acid, required a column containing only 70 percent of the theo- retical plates required of no entrainer is used. Two commercial processes have been developed for the separation of toluene using azeotropic distillation. One using an aqueous solution of methyl ethyl ketone and wa- ter and the other using methanol. Both processes operate on a narrow boiling range concen-
Is decantation applicable for the separation of solid-liquid mixtures?
James Bond can help us with this as his martini is shaken and not stirred. The fluids and ice in the shaker are mixed, but when the cocktail is decanted, the chunks of ice (a solid) remain in the decanter. There is a bit more to this as it is more challenging to decant a liquid and leave something like a solid precipitate in the decanter, but with practice, and possibly some help from filtration media, the task can be accomplished.
Name the substance which is commonly employed as a cooling agent in the refrigerator?
freon
What is the principle of conductivity?
The common laboratory conductivity meters employ a potentiometric method and four electrodes. Often, the electrodes are cylindrical and arranged concentrically. The electrodes are usually made of platinum metal. An alternating current is applied to the outer pair of the electrodes. The potential between the inner pair is measured. Conductivity could in principle be determined using the distance between the electrodes and their surface area using the Ohm's law but generally, for accuracy, a calibration is employed using electrolytes of well-known conductivity. Industrial conductivity probes often employ an inductive method, which has the advantage that the fluid does not wet the electrical parts of the sensor. Here, two inductively-coupled coils are used. One is the driving coil producing a magnetic field and it is supplied with accurately-known voltage. The other forms a secondary coil of a transformer. The liquid passing through a channel in the sensor forms one turn in the secondary winding of the transformer. The induced current is the output of the sensor.
What reactions can be employed for getting unsymmetrical alkanes in good yield?
Corey-House reaction
What is the Use of autoclave and it's principle?
Sterilization of instruments. Heat is the usual principle employed.
What principle is employed in the operation of an artificial kidney?
Dialyisis
The principle employed in the operation of an artificial kidney is what?
dialysis
What would you say is the principle means of characterization employed by the author?
thoughts
How is science and technology utilized in desalination?
Desalination is the process of removing salt from sea water in order to make drinking water. The method of doing this typically uses reverse osmosis. Distillation is sometimes employed, usually using vacuum distillation.
What does Archimedes principle and the buoyancy have in common and where is it employed?
Archimedes' principle is the statement that says buoyancy exists, and explains how to calculate its magnitude. The principle is applied extensively in the maritime shipping and hot-air balooning industries.
What is the name for making sure there is no contamination in a liquid?
Various means are used to purify liquids for use or analysis. Common methods employed are filtration, precipitation, and distillation.
When drawing objects in proportion Transfer of Scale is employed more than any other principle true or false?
True.
What is the name of the principle employed by early astronomers to determine the distances to celestial objects using the displacement of the apparent position of an object viewed along two different?
parallax
What is the meaning of TAR?
A sailor; a seaman., A thick, black, viscous liquid obtained by the distillation of wood, coal, etc., and having a varied composition according to the temperature and material employed in obtaining it., To smear with tar, or as with tar; as, to tar ropes; to tar cloth.
What is the correct sentence employed at or employed with?
The correct sentence would be "employed at." For example, "She is employed at the bank."
What type of protection scheme is employed for protection of a large form of transformer against shortcircuit with neat sketchs discuss the working principle?
You've got to be kidding! The answer would require a chapter in a textbook, and not a response in this forum.
