This note describes the use of alternative solvents for sample clean-up with Agilent EnviroPrep columns to replace the toxic dichloromethane. Several solvent mixtures were investigated for use with EnviroPrep columns, and the effect of the eluent on the elution of the standard test mixture described in the EPA methodology is described.
The document addresses the toxicity of dichloromethane, a recommended eluent for EPA 3640a sample clean-up procedures. It proposes ethyl acetate and cyclohexane as alternative solvents to reduce health risks while maintaining separation efficiency.
Experiments were conducted using Agilent EnviroPrep columns (part number PL1210-6120EPA) with a standard test mixture containing corn oil, bis(2-ethylhexyl) phthalate, methoxychlor, perylene, and sulfur. The study evaluated pure ethyl acetate, pure cyclohexane, and various mixtures of the two solvents to determine optimal polarity for chromatographic separation.
| Column Part Number | PL1210-6120EPA |
|---|---|
| Flow Rate | 6.0 mL/min |
| Injection Volume | 200 pL |
A 1:1 mixture of ethyl acetate and cyclohexane was determined to be a suitable replacement.
Ethyl acetate and cyclohexane were selected as relatively safe chemicals to use.