Nature was created in a very high level of complexity. We will not find the element or compound that stands alone, in the sense not mixed with other compounds. For some purposes such as the synthesis of chemical compounds it need raw materials of chemical compounds in pure state. Therefore, the separation process is needed in this regard. An example such as petroleum. Petroleum is a complex mixture of hydrocarbons plus organic compounds of sulfur, oxygen, nitrogen and compounds containing metal constituents, especially Nickel, Iron and Copper.
To get petroleum, processing of crude oil is distilled to separate them into different fractions according to boiling point of the compound. The results of this separation produces a variety of fuels, which in turn are used to different specifications.
The example above is clear evidence of the separation process in chemical industry.Separation process broadly divided into two, namely the process of mechanical separation and chemical separation processes. You all must have guessed what kind of mechanical separation and chemical separation. Mechanical separation is a separation that utilizes the mechanical properties of a heterogeneous compound as an example we separate the water by using a sand filter. Unlike the chemical separation, the separation takes advantage of the chemical properties of a compound as an example of the distillation process earlier.
Many methods used in performing the separation. Principally, the process of separation is the separation process by which the formation of a new phase, so that it become a heterogeneous mixture that is easy to separate. So whenever possible we prevent the formation of a new phase in a compound that is easy to separate.
Here is an example of some common methods of separation that we hear in chemical engineering:
1. Distillation is a method of separating chemical substances based on differences in speed of evaporation (volatility) of materials. In our simpler analogy as follows: When we have a duty to separate a mixture of ethanol with water, then the method that we must use the method of distillation, Why? Because ethanol and water has a different speed of evaporation. When we are heating up the mixtures, ethanol will evaporate faster than water. Because ethanol has a lower boiling point than water. Ethanol vapor, which in the next process was changed from gas phase into liquid phase again with contacting steam with cold water.
2. Crystallization is the process of formation of solid material from the deposition solution, meltdown mixtures, or more rarely the direct deposition from the gas. Crystallization is also a chemical separation technique between solid-liquid material, in which occurs the mass transfer (mass transfer) of the solutes (solutes) from the liquid solution to solid crystal phase.
3. Chromatography is a separation technique based on the difference in speed of propagation of a mixture of components in a particular medium. More details, like this: In chromatography, the components are divided into two phases. Stationary phase will hold components while mobile phase mixture will dissolve the substance mixture components. Components are easily retained on the stationary phase will be missed. While the components that are easily dissolved in the mobile phase will move faster.
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