NEMI Method Summary

Method Summary Information

Method Number: 375.3 Media: WATER
Revision: Issued 1974; Editorial Revision 1978
Method Source: U.S. EPA National Exposure Research Laboratory (NERL) [formerly EMSL]
Analytes in this method
Subcategory: INORGANIC
Official Name: Sulfate (Gravimetric)
Descriptive Name Sulfate by Gravimetric Determination
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)
31754 Byte file
Brief Method
Summary:
 Sulfate is precipitated as barium sulfate in a hydrochloric acid medium by the addition of barium chloride. After a period of digestion, the precipitate is filtered, washed with hot water until free of chloride, ignited, and weighed as BaSO4.
Scope And
Application:
 This method is applicable to drinking, surface and saline water; and domestic and industrial wastes.
Applicable
Conc Range:
 10mg/L - * (* Method does not specify an upper detection limit.)
Interferences: (1) High results may be obtained for samples that contain suspended matter, nitrate, sulfite and silica.
(2) Alkali metal sulfates frequently yield low results. This is especially true of alkali hydrogen sulfates. Occlusion of alkali sulfate with barium sulfate causes the substitution of an element of lower atomic weight than barium in the precipitate. Hydrogen sulfate of alkali metal acts similarly and decomposes when heated. Heavy metals such as chromium and iron, cause low results by interfering with complete precipitation and by formation of heavy metal sulfates.
QC Requirements: not included
Sample Handling: Collect 50 mL samples in either glass or plastic bottles. Refrigerate at 4oC until analysis. Analyze within 28 days.
Max Holding Time:
 28 days (MCAWW, Table 1).
 
Relative Cost: Less than $50
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