The first thing we are going to do before entering fully into the meaning of the term leaching is to discover its etymological origin. In this case, we can establish that it derives from Latin. Exactly we can establish that it is the result of the sum of two well-differentiated lexical components of said language:
-The noun "lixivia", which can be translated as "lye".
-The suffix "-cion", which is used to indicate "action and effect."
The idea of leaching is used in the field of chemistry . This is what the act and result of leaching is called: dividing the soluble parts and the insoluble parts of a substance by using a solvent .
Leaching is also known as solid-liquid extraction , since it consists of the use of a liquid solvent with a pulverized solid, an action that allows the dissolution of the soluble elements of the solid.
Through leaching, in short, it is possible to extract solutes from a solid thanks to the use of a liquid solvent . When the phases contact, the solutes diffuse into the liquid, achieving separation.
Leaching is a process that develops in different contexts. Through it you can obtain sugar , dyes or oils , for example.
In the field of metallurgy , leaching makes it possible to extract useful species from a mineral, using reagents that are responsible for its dissolution. Copper , silver and gold are metals that are usually extracted through leaching, which can be carried out in different ways (by agitation, in heaps, in dumps, etc.).
In the field of mining we have to establish that different types of leaching can be carried out. Thus, for example, among the most significant are the following:
-Heap leaching. This is carried out, above all, to be able to recover what are the values of the so-called "low grade" minerals. Likewise, we can highlight that, currently, for example, it is used in just over a hundred mines in the world and, specifically, on silver and gold ores. No less interesting is knowing that this procedure has its origins five centuries ago and was discussed for the first time in the work "De Re Metallica" (1557) by Georgius Agricola.
-Leaching from landfills. Specifically, this other modality is being undertaken in what are sulphurous copper ore landfills. Thus, these are wetted with water or sulfuric acid to proceed to leach out what are the copper salts.
Likewise, there are also two other well-known modalities: in situ leaching and so-called pressure leaching.
The concept of leaching is used in ecology to refer to the sliding of polluting agents and waste into the seas and rivers. Water is responsible for carrying away these substances that can cause significant damage to the environment.
Similarly, geology uses the notion of leaching to name the washing of a geological layer or stratum through water .