The extraction process depend on the solubility of a particular species in the extracting solvent from aqueous solutions. Methanol is suitable for extraction than Ethanol, because most of the polar or mid polar compounds get dissolved in methanol as compare to ethanol and it has low boiling point and high vapor pressure so can be useful to separate the extracted compound by easy drying.
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methanol was more efficient compare to ethanol.Methanol is a polar solvent and non polar molecules can be picked up in methanol.
Mostly methanol is used for extraction various polar compounds but certain group of non polar compounds are fairly soluble in methanol if not readily soluble.