Method 231.2: Gold (Atomic Absorption, Furnace Technique)


United States
Environmental Protection
\r ^1 M^k. Agency

www.epa.gov	1978

Method 231.2: Gold (Atomic
Absorption, Furnace Technique)

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METHOD #: 231.2

TITLE:

ANALYTE:

Approved for NPDES (Issued 1978)
Gold (AA, Furnace Technique)
CAS # Au Gold 7440-57-5

INSTRUMENTATION:	AA

STORET NO.	71910

Optimum Concentration Range:	5-100 yg/L

Detection Limit:	1 /xg/L

1.0 Preparation of Standard Solution

1.1	Stock solution: Prepare as described under "direct aspiration method".

1.2	Prepare dilutions of the stock solution to be used as calibration standards at
the time of analysis. These solutions are also to be used for "standard
additions".

1.3	The calibration standard should be diluted to contain 0.5% (v/v) HNOs.

2.0 Sample Preservation

2.1 For sample handling and preservation, see part 4.1 of the Atomic Absorption
Methods section of this manual.

3.0 Sample Preparation

3.1 Prepare as described under "direct aspiration method". Sample solutions for
analysis should contain 0.5% (v/v) HNOs.

4.0 Instrument Parameters (General)

4.1	Drying Time and Temp: 30 sec-125°C.

4.2	Ashing Time and Temp: 30 sec-600°C.

4.3	Atomizing Time and Temp: 10 sec-2700°C.

4.4	Purge Gas Atmosphere: Argon

4.5	Wavelength: 242.8 nm.

4.6	Other operating parameters should be set as specified by the particular
instrument manufacturer.

5.0 Analysis Procedure

5.1 For the analysis procedure and the calculation, see "Furnace Procedure" part
9.3 of the Atomic Absorption Methods section of his manual.

6.0 Notes

6.1

The above concentration values and instrument conditions are for a

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Perkin-Elmer HGA- 2100, based on the use of a 20 uL injection, continuous
flow purge gas and non-pyrolytic graphite.

6.2	The use of background correction is recommended.

6.3	For every sample matrix analyzed, verification is necessary to determine that
method of standard addition is not required (see part 5.2.1 of the Atomic
Absorption Methods section of this manual).

6.4	If method of standard addition is required, follow the procedure given earlier
in part 8.5 of the Atomic Absorption Methods section of this manual.

6.5	Data to entered into STORET must be reported as /xg/L.

Precision and Accuracy

7.1 Precision and accuracy data are not available at this time.

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