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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.
Acid–base extraction is a subclass of liquid–liquid extractions and involves the separation of chemical species from other acidic or basic compounds. [1] It is typically performed during the work-up step following a chemical synthesis to purify crude compounds [2] and results in the product being largely free of acidic or basic impurities.
If the constituents of a mixture are completely miscible in all proportions with each other, the type of azeotrope is called a homogeneous azeotrope. Homogeneous azeotropes can be of the low-boiling or high-boiling azeotropic type. For example, any amount of ethanol can be mixed with any amount of water to form a homogeneous solution.
Refining is used primarily in the petroleum industry, whereby crude oil is heated and separated into stages according to the condensation points of the various elements. Distillation, widely used in petroleum refining and in purification of ethanol separates volatile liquids on the basis of their relative volatilities. There are several type of ...
[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.
Mixtures contain more than one chemical substance, and they do not have a fixed composition. Butter, soil and wood are common examples of mixtures. Sometimes, mixtures can be separated into their component substances by mechanical processes, such as chromatography, distillation, or evaporation. [13]
The addition of a material separation agent, such as benzene to an ethanol/water mixture, changes the molecular interactions and eliminates the azeotrope. Added in the liquid phase, the new component can alter the activity coefficient of various compounds in different ways thus altering a mixture's relative volatility.
Acetic acid (CH 3 COOH) and ammonium (NH + 4) are good examples. Acetic acid is extremely soluble in water, but most of the compound dissolves into molecules, rendering it a weak electrolyte. Weak bases and weak acids are generally weak electrolytes. In an aqueous solution there will be some CH 3 COOH and some CH 3 COO − and H +.