How To Extract and Wash What

Here are some practical examples of washings and extractions, covering various types and mixtures and separations and broken down into the four classifications listed above. 

A strong organic acid. Extract into sat d (saturated) sodium bicarbonate solution. 

A weakly acidic organic acid. Extract into 10% NaOH-water solution. The strong base is needed to rip the protons out of weak acids (they don t want to give them up) and turn them into salts Then they ll go into the NaOH-water layer. 

An organic base. Extract with 10% HCl-water solution. The strong acid turns the base into a salt (This turning the whatever into a salt that dissolves in the water solution should be pretty familiar to you by now. Think about it.). Then the salt goes into the water layer. 

A neutral organic. If you ve extracted strong acids first, then weak acids, then bases, there are only neutral compound(s) left. If possible, just remove the solvent that now contains only your neutral compound. If you have more than one neutral compound, you may want to extract one from the other(s). You ll have to find two different immiscible organic liquids, and one liquid must dissolve ONLY the neutral organic compound you want A tall order. You must count on one neutral organic compound being more soluble in one layer than in the other. Usually the separation is not clean—not complete. And you have to do more work. 

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Washing and Extracting Various Things How To Extract and Wash What... 

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