Solvents for Extraction and Partitioning Distribution

The partitioning of a substance between two liquid phases (multistage partitioning, partition chromatography) and the extraction of solids require similar properties of a solvent [50-55]. When a substance has to be partitioned, a solvent system with limited miscibility of the components is required in order that the substance dissolves to a different extent in the two phases. The greater the chemical differences between any two solvents, the more limited their miscibility. Other requirements that the solvent system must fulfil are, inter alia, a favorable partition coefficient (the average partition coefficient of the component mixture should be between ca. 0.2 and 5), as high a separation 

Solvent fbp/°C Suitable solvent for Second solvent for mixture  

Water 1.000 100.0 Salts, amides, some carboxyhc adds Acetone, alcohols, 1,4-dioxane, acetonitrile 

Methanol 0.762 64.5 General, esters, nitro and bromo compounds Water, diethyl ether, benzene 

2-Methoxyethanol 0.657 124.6 Sugars Water, benzene, diethyl ether 

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