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A separation process is a method that converts a mixture or a solution of chemical substances into two or more distinct product mixtures, [1] a scientific process of separating two or more substances in order to obtain purity. At least one product mixture from the separation is enriched in one or more of the source mixture's constituents.
Azeotropes are useful in separating zeotropic mixtures. An example is zeotropic acetic acid and water. It is very difficult to separate out pure acetic acid (boiling point: 118.1 °C): progressive distillations produce drier solutions, but each further distillation becomes less effective at removing the remaining water.
Acid-base extraction can be used to easily separate out the acidic starting materials from the ester. By rinsing the crude product mixture with a weak base (e.g. sodium bicarbonate), the carboxylic acid and alcohol will be washed away with the aqueous layer, leaving purified ester in the organic layer. [14]
The product is isolated from the mixture by the following work-up: [3] Synthesis of 4-methylcyclohexene with work-up step in red. A concentrated solution of sodium chloride in water, known as a brine solution, is added to the mixture and the layers are allowed to separate. The brine is used to remove any acid or water from the organic layer.
Water purification combines a number of methods to produce potable or drinking water. Downstream processing refers to purification of chemicals, pharmaceuticals and food ingredients produced by fermentation or synthesized by plant and animal tissues, for example antibiotics, citric acid, vitamin E, and insulin.
Homogeneous mixtures can be separated by molecular separation processes; these are either equilibrium-based or rate-controlled. Equilibrium-based processes are operating by the formation of two immiscible phases with different compositions at equilibrium, an example is distillation (in distillation the vapor has another composition than the ...
[8] [9] Mixtures differ from chemical compounds in the following ways: The substances in a mixture can be separated using physical methods such as filtration, freezing, and distillation. There is little or no energy change when a mixture forms (see Enthalpy of mixing). The substances in a mixture keep their separate properties.
Another example of this application is extracting anisole from a mixture of water and 5% acetic acid using ether, then the anisole will enter the organic phase. The two phases would then be separated. [citation needed] The acetic acid can then be scrubbed (removed) from the organic phase by shaking the organic extract with sodium bicarbonate.