NEMI Method Summary


Method Summary Information

Method Number:

D3113A

Media:

WATER

Revision:

Reapproved 1998. Current edition approved Nov. 15, 1992.

Method Source:

ASTM International

Subcategory:

INORGANIC

Analytes in this method

Official Name:

Standard Test Methods for Sodium Salts of EDTA in Water

Descriptive Name

EDTA: Total (Chelated and Unchelated) Sodium Salt of EDTA (Method A)

Source Info:

ASTM International
100 Barr Harbor Drive West
Conshohocken, PA 19428
Telephone: (610) 832-9500
Fax: (610) 832-9555
Email: service@astm.org

Citation:

ASTM Volume 11.02

Brief Method
Summary:

The intensity of the red-colored zirconium-xylenol orange complex formed in a strong acid medium is reduced in the presence of free EDTA or its metallic complexes through formation of a more stable zirconium-EDTA complex. The reduction in color intensity is a measure of total EDTA in the sample reported as milligrams per litre of Na₄EDTA.

Scope And
Application:

This test method as described may be applied to waters containing free Na₄EDTA or heavy metal or alkaline earth chelates of Na₄EDTA either individually or in combination, in concentrations from 0.5 to 20 mg/L. Higher concentrations may be determined by dilution.

Applicable
Conc Range:

0.5-20

Interferences:

Nitrilotriacetate (NTA) produces erratic values in the test for waters treated with NTA or mixtures of NTA and EDTA.
Polyphosphates interfere in this analysis and produce high values for the EDTA concentration. Interference from concentrations up to 12 mg/L can be eliminated by adding 1 mL of a thorium nitrate solution.
Other chelating agents may react the same as EDTA.

QC Requirements:

Sample Handling:

Collect the samples in accordance with Practice D 1066 or Practices D 3370 as applicable.

Max Holding Time:

Relative Cost:

Unknown

URL to obtain ordering information for this method:

http://www.astm.org/cgi-bin/SoftCart.exe/DATABASE.CART/PAGES/D3113.htm?E+mystore

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Method Summary Information