Methylene chloride would typically be considered a sem-polar solvent. A true non-polar solvent, such as hexane, has specific use in WW extraction. It is quite good at extracting highly non-polar compounds, such as PCBs, pesticides, aliphatic hydrocarbons, etc.
Methylene chloride is a broader range solvent, as you will also be able to extract semi-polar organics from water, such as phenols, amines, aromatic hydrocarbons, etc.
The non-polar solvents conveniently separate very well from water and don't pick up water, so they are very nice to use for a quick shake-and-shoot analysis.
To extract organic compounds for water, which is a polar solvent, an immiscible non-polar solvent must be used so that there will be two phases. Typically, dichloromethane is used as a non-polar solvent for extraction of organic compounds from waste water. USEPA method 625 or 1625 describe a procedure to do this.
Methylene chloride would typically be considered a sem-polar solvent. A true non-polar solvent, such as hexane, has specific use in WW extraction. It is quite good at extracting highly non-polar compounds, such as PCBs, pesticides, aliphatic hydrocarbons, etc.
Methylene chloride is a broader range solvent, as you will also be able to extract semi-polar organics from water, such as phenols, amines, aromatic hydrocarbons, etc.
The non-polar solvents conveniently separate very well from water and don't pick up water, so they are very nice to use for a quick shake-and-shoot analysis.