What are four characteristics of a good extraction solvent?

A substance that dissolves the solute is solvent. High solubility, immiscible, volatile and less toxicity are the characteristics.

A good solvent for the extraction should have high and good solubility as the compound to be extracted must be soluble in the solvent for the extraction.

They should be immiscible as the solution to be extracted must not mix with the extracting solvent otherwise the extraction process could not be done.

The extracting solvent must be volatile so that it can be separated from the extracted compound or the substance. Also, they should be less toxic and safe to use so that the compound can be extracted without any environmental harm.

Therefore, high solubility, immiscible, volatile and less toxicity are the characteristics of a good extraction solvent.

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A good extraction solvent should have a strong solubilizing capability for the compound of interest, it should be immiscible or only weakly misciblewith the matrix solvent ( the first solution or mixture containing the compound from its natural source, e.g., water/ether. water/ chloroform, etc. If possible the extraction solvent should be non-flammable, non-toxic or of low toxicity, reasonably volatile, and of low eco-impact. Inexpensive and available, of high purity , and shelf stable. If one is determining the compound of interest by UV/Vis spectrophotometry or fluorescence, the solvent should have extremely low absobance or emission at the wavelength of analysis

•high solubility for the solute and low solubility for the carrier liquid.

•density difference vs. the carrier liquid greater than 150 kg/m. ...

•mid-level interfacial tension (5–30 dyne/cm)

•high resistance to thermal degradation.