NEMI Method Summary


Method Summary Information

Method Number:

3030 F

Media:

WATER

Revision:

Standard Methods Online

Method Source:

Standard Methods

Subcategory:

SAMPLING/PREPARATION

Official Name:

Nitric Acid-Hydrochloric Acid Digestion of Samples

Descriptive Name

Nitric and Hydrochloric Acid Digestion

Source Info:

Standard Methods Online is jointly produced by the American Public Health Association (APHA), the American Water Works Association (AWWA), and the Water Environment Federation (WEF).
These organizations may be contacted by phone for more information on Standard Methods Online:
APHA: (301) 893-1894
AWWA: (800) 926-7337, (1-303-794-7711, outside U.S. / Canada)
WEF: (800) 666-0206 (1-703-684-2452 outside U.S. / Canada)

Citation:

Standard Methods Online

Brief Method
Summary:

This method should be used for digesting samples containing Ag. For samples with Ag concentrations > 1 mg/L, dilute to < 1 mg/L for flame AA methods and < 25 ug/L for electrothermal analysis. When using more than 100 mL of sample during digestion, determine recovery for each matrix to verify method validity. I. Total HNO3/HCl: Determine sample volume for the expected metals concentration (see abstract in Method 3030-E). To well-mixed sample add 3 mL concentrated HNO3 and evaporate to < 5 mL. Cool and add 5 mL concentrated HNO3. Cover container and reflux over hot plate. Continue this process until digestion is complete and total volume is < 5 mL. Add 10 mL 1+1 HCl and 15 mL water per 100 mL final volume. Heat for 15 minutes to dissolve precipitate or residue. Cool and rinse container walls with water. Filter, centrifuge, or let stand overnight to remove insoluble material. II. Recoverable HNO3/HCl: To well-mixed sample add 2 mL 1+1 HNO3 and 10 mL 1+1 HCl, and evaporate to < 25 mL. Cool then filter, centrifuge, or let stand overnight to remove insoluble material. Bring volume to 100 mL and mix. Samples totally digested by acid digestion techniques yield comparable precision and bias, however, the minimal amount of acid should be used in the digestion as acid adds metals to the sample.

Scope And
Application:

This method is applicable to the digestion of metals in waste and wastewater samples.

Applicable
Conc Range:

Interferences:

Metals introduced during preliminary treatment from equipment common to environmental labs.

QC Requirements:

Check reagent grade acids for purity. Process blanks through all digestion and filtration steps.

Sample Handling:

Collect sample in plastic or glass container which has been rinsed with 1+1 HNO3. Adjust the pH of the sample to < 2 with HNO3. For dissolved metals, filter samples immediately. Analyze within 6 months.

Max Holding Time:

6 months

Relative Cost:

Less than $50

URL to obtain ordering information for this method:

http://www.standardmethods.org/

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Method Summary Information