NEMI Method Summary

Method Summary Information

Method Number: 413.1 Media: WATER
Revision: Editorial Revision 1978
Method Source: U.S. EPA National Exposure Research Laboratory (NERL) [formerly EMSL]
Analytes in this method
Subcategory: ORGANIC
Official Name: Oil And Grease (Gravimetric, Separatory Funnel Extraction)
Descriptive Name Oil and Grease in Water by Extraction and Gravimetery
Source Info: U.S.EPA National Exposure Research Laboratory (NERL)
Microbiological and Chemical Exposure Assessment Research Division (MCEARD)
[formerly the Environmental Monitoring Systems Laboratory (EMSL), Cincinnati, OH]
26 West Martin Luther King Drive
Cincinnati, Ohio 45268-0001
Fax: 513-569-7757
email: DWmethods.help@epa.gov
Citation: Methods for the Chemical Analysis of Water and Wastes (MCAWW) (EPA/600/4-79/020)
  Byte file
Brief Method
Summary:
 The sample is acidified to a low pH ( < 2) and serially extracted with fluorocarbon-113 in a separatory funnel. The solvent is evaporated from the extract and the residue weighed.

The definition of oil and grease is based on the procedure used. The nature of the oil and/or grease, and the presence of extractable non-oily matter will influence the material measured and interpretation of results.
Scope And
Application:
 This method includes the measurement of fluorocarbon-113 extractable matter from surface and saline waters, industrial and domestic wastes. It is applicable to the determination of relatively non-volatile hydrocarbons, vegetable oils, animal fats, waxes, soaps, greases and related matter. The method is not applicable to measurement of light hydrocarbons that volatilize at temperatures below 70oC. Petroleum fuels from gasoline through #2 fuel oils are completely or partially lost in the solvent removal operation. Also, some crude oils and heavy fuel oils contain a significant percentage of residue-type materials that are not soluble in fluorocarbon-113. Accordingly, recoveries of these materials will be low.
Applicable
Conc Range:
 5 to 1000 mg/L of extractable material
Interferences:
QC Requirements: None.
Sample Handling: A representative sample of 1 liter volume should be collected in a glass bottle. If analysis is to be delayed for more than a few hours, the sample is preserved by the addition of 5 mL HCl at the time of collection and refrigerated at 4oC. (Note: Table 1 of MCAWW manual specifies preserving to pH < 2 with H2SO4)

Because losses of grease will occur on sampling equipment, the collection of a composite sample is impractical. Individual portions collected at prescribed time intervals must be analyzed separately to obtain the average concentration over an extended period.
Max Holding Time:
 28 days (MCAWW, Table 1)
 
Relative Cost: $51 to $200
7280
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