Liuottimteokset

Liuottimteokset, often translated as solvent extraction or liquid-liquid extraction, is a fundamental chemical engineering and analytical chemistry technique. It involves the separation of a substance from one solvent into another immiscible solvent. This process relies on the differential solubility of the target compound in two liquid phases.

The principle behind solvent extraction is the partitioning of a solute between two liquid phases that do not mix. When a solution containing the solute is brought into contact with a second, immiscible solvent, the solute will distribute itself between the two solvents based on its relative affinity for each. This distribution is governed by the Nernst partition law, which states that at equilibrium, the ratio of the solute's concentration in the two phases is constant at a given temperature.

Solvent extraction finds wide applications across various fields. In chemical industries, it is used for the purification of compounds, recovery of valuable materials from waste streams, and the separation of metals. In analytical chemistry, it serves as a sample preparation technique to isolate and concentrate analytes before measurement, improving detection limits and reducing interference. It is also employed in pharmaceutical manufacturing for drug purification and in environmental analysis for the detection of pollutants. The choice of solvents is crucial for effective separation, and it depends on factors such as the polarity of the solute, immiscibility of the solvents, and safety considerations.