Leaching process is influenced by processes such as desorption, complexation, and mineral dissolution. Commonly the extract is the product or intermediate product and the residue is a waste or byproduct.
Leaching is one of the oldest operations in chemical industries which involves the use of solvent to remove a solute form a solid mixture.
A solvent dissolves a solute, which is an element. As a result, the solvent will turn into a liquid, while the solute will be the component extracted from the solid matrix. Furthermore, in tea for example, the solute would be the extracted green tea, and the solvent would be hot water. In this example, the hot water removes substances from the solid matrix, i.e., the tea in the bag.
Leaching process is widely used in the biological and food processing industries for the separation of sugar from sugar beets with hot water, or for the extraction of oil from peanuts, soybeans, and sunflower seeds. Likewise, many pharmaceutical products are obtained by leaching plant roots, leaves and stems.
The advantages of leaching process include:
*Easy to execute.
*It is not very harmful when compared to pyrometallurgical methods.
*Does not generate any gaseous pollutants.
Leaching extraction process
