Leaching is one of many solid-fluid separation processes that are carried out in
the chemical, mineral and related industries. In fact, it is one of the oldest unit
operations in the chemical industries. The fundamental principle behind leaching
is the removal of a soluble material from an insoluble, permeable solid phase. The
soluble fraction, solid or liquid, may exist mechanically in the pore structure of
the insoluble material or chemically combined with that material. This soluble
material is removed through dissolution in a dissolving solvent. The most familiar
example of leaching is the extraction of tea and coffee, and most importantly
mineral recovery.
The rate of leaching (extraction) is affected by many physical and chemical phenomena. Mass transfer and equilibriumphenomena obviously playmajor roles. The process of leaching consists of the following steps: (i) The solvent diffuses into the solid phase; (ii) The diffused solvent dissolves the solutes (i.e. transfer the solute to the liquid phase). Leaching is always followed by solvent recovery, which involves another mass transfer operation; such as filtration.
The separation of materials of different chemical types and solubilities by selective solvent action; that is, some materials are more soluble in one solvent than in another, hence there is a preferential extractive action; used to refine petroleum products, chemicals, vegetable oils, and vitamins.
The principal of solvent extraction is Nernst's distribution law. It states that "if a solute "X" distributes between two non-miscible solvents 'a' and 'b' at a constant temperature and "X" is in the same molecular for in both of them, then the ratio of the concentrations of "X" in the two solvents is a constant quantity."
i.e. Concentration of "X" in solvent 'a' = C1 = K(constant) Concentration of "X" in solvent 'b' = C2
The constant K is called the partition coefficient and is also denoted by Kd (distribution constant).
For example, iodine, a violet crystalline solid when added to a mixture of two immiscible liquids, water and carbon tetrachloride, distributes in both of them. The value of K in this case is 85 at room temperature (i.e. 298 K).
Plant source are gotten from wild (forest)& cultivated source(farmland,reserves).Before collectin we must identify and authenticate the plant then we process by either over drying or air drying at a temperature of about 35¤-40¤c,but in stems or roots the temp. Should be between 40 and 60¤c. Powdering is also involved. The extraction types are:Marceration,percolation,soxhilete and super critical fluid extraction.
Separation of a component from a mixture with the aid of solvent which is miscible with this component but immiscible with the initial solvent of the mixture.
Solvents extraction is a separation method used in chemistry.
A component of a solution is extracted by the use of a selective solvent for this component.
The partial removal of a substance from a solution or mixture by dissolving in another,immiscible solvent in which it is more soluble
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conclusion for extraction of bitumen
Because you are providing a greater surface area of contact between the aqueous layer and organic layer
separation of immicible solvent
Essential oils are separated from plants by solvent extraction or water vapor extraction.
- It is used as a jet fuel - It is used as a solvent in solvent extraction of metals, etc.
hot water extraction , aqueous extraction, solvent extraction
conclusion for extraction of bitumen
hot water extraction , aqueous extraction, solvent extraction
By solvent extraction with water. By fractional distillation.
Pivalic Acid
Because you are providing a greater surface area of contact between the aqueous layer and organic layer
we can say this because both of these are separation technique
You think probable to a solvent for the solvent extraction method.
separation of immicible solvent
Essential oils are separated from plants by solvent extraction or water vapor extraction.
- It is used as a jet fuel - It is used as a solvent in solvent extraction of metals, etc.
Two methods are used: solvent extraction or water vapor extraction.