30% Acetic acid- 70% Water and Methylene Chloride: Two Liquid Phases for Partition Extractive Work-ups

Because Kilomentor puts a huge emphasis on simple, rugged, powerful separation methodologies, I am very interested in pairs of liquids that are not miscible with each other but where both have good solvent properties for a substantial range of  organic compounds. The reason is that liquid-liquid extraction is a simple and scalable purification method.

I have in my old laboratory notes mention that a mixture of two phases: one- methylene chloride, and the other- 30% acetic acid-70% water, was used to remove the non-polar contaminants from a peptide mixture made up from among neutral amino acids. It seems to me that the addition of the very good solvent acetic acid will have increased the number of polar or semi-polar substrates so substantially in this predominantly aqueous phase that it in competition with methylene chloride could separate some important mixtures. Furthermore, the dissolving power of methylene chloride probably can be further modulated by adding into it toluene or hexanes

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