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Region 9 Laboratory SOP 275
TPH Extraction Using CLLE
Summary
This SOP describes the procedures used to extract hydrocarbon fuels or oils from water samples using continuous liquid-liquid extraction. This procedure is applicable to finished water, groundwater, and waste water samples. This SOP is based on procedures in SW-846 method 3520C, Continuous Liquid-Liquid Extraction, Revision 3, December 1996.
A measured volume of aqueous sample, approximately one liter, is placed in a continuous liquidliquid extractor. The sample pH is adjusted to <2 with a 6N hydrochloric acid solution, spiked with a surrogate solution and extracted with methylene chloride for eighteen to twenty-four hours. The extract is dried with sodium sulfate and concentrated to 5 mL using a Kuderna-Danish apparatus. The extract is analyzed by GC with a flame ionization detector as documented in SOP #385.