EQUIPMENT

1. Perkin-Elmer Model 4100 ZL Atomic Absorption Spectrophotometer
2. Perkin-Elmer AS-71 Autosampler
3. Antimony electrodless discharge lamp
4. Perkin-Elmer System 2 EDL power supply
5. Hamilton Digital Diluter
6. Pyrolytically coated, platform graphite tubes
7. 2 mL sample cups

INSTRUMENT PARAMETERS

1	Wavelength	217.6 nm
2	Slit Width	0.7 nm
3	Slit Height	LOW
4	Signal Type	Zeeman AA
5	Signal Measurement	Peak Area
6	Read Time	5 seconds
7	Read Delay	0 seconds
8	BOC Time	2 seconds
9	Sample Volume	20 micro L
10	Modifier Volume	10 micro L

FURNACE PARAMETERS

STEP	TEMP (°C)	Time (sec)		INT. FLOW
		RAMP	HOLD
1	110	10	25	250
2	130	10	35	250
3	1300	5	30	250
4	1900	0	5	0
5	2400	1	2	250

GAS

1. Argon 99.99%

STANDARDS

1. Stock Solutions
   1. 1000 ppm Antimony: Use certified, NIST traceable Plasma Grade Standard.
   2. 100 ppm Antimony: Pipet 10 mL of 1000 ppm antimony standard into a 100 mL volumetric flask. Dilute to volume with deionized water and mix well. Prepare fresh daily.
   3. 1 ppm Antimony: Pipet 1 mL of 100 ppm antimony standard into a 100 mL volumetric flask. Dilute to volume with deionized water and mix well. Prepare fresh daily.
2. Instrument Calibration Standards:
   1. 20, 60, and 100 ppb Antimony - use the following settings on the Hamilton digital diluter to make dilutions of the 1 ppm antimony standard to produce the 60 and 100 ppb antimony standard. Make the 20 ppb antimony standard by diluting the 100 ppb antimony standard.

      Standard Used	Diluter Settings		Final Concentration ppb
      	Diluent	Sample
      100 ppb	32	80	20
      1 ppm	47	30	60
      1 ppm	36	40	100

      Note: This protocol produces 4 mL of the 20 and 100 ppb antimony standard and 5 mL of 60 ppb antimony standard.

MATRIX MODIFIER REAGENTS

1. Palladium Nitrate: Pd(NO₃)₂
2. Magnesium Nitrate: Mg(NO₃)₂.6H₂O

MATRIX MODIFIER PREPARATION

1. Weigh 0.1083 g palladium nitrate into a 100 mL amber volumetric flask.
2. Add 0.0518 g magnesium nitrate to the 100 mL volumetric flask.
3. Dissolve and dilute to volume with deionized water and mix well.

AUTOSAMPLER LOADING

1. Load the autosampler tray in the following manner:

   Positions 1-34	client samples
   Position 35	matrix modifier
   Position 36	deionized water
   Position 37	20 ppb antimony standard
   Position 38	60 ppb antimony standard
   Position 39	100 ppb antimony standard
   Position 40	quality control sample

PROCEDURE

1. Use the same procedure as given in the procedure section for the lead graphite furnace method p. 125-127, with the following changes:
   1. Step 2 - change to - Install the antimony electrodeless discharge lamp. With the "MOD" button on (green light on), set the power output level to 330 milliamps. Allow the lamp to warm up for 30 minutes. The set current will increase as the lamp warms up. DO NOT READJUST.
   2. Step 6 - change to - Scroll down to and click on "WATER_SB.GEL"
   3. Step 15 - change to: Scroll down to and click on "SB_H2O.IDW"

QUALITY CONTROL

1. If the r value for the calibration curve is less than .990, remake the standards and recalibrate.
2. Analyze the quality control sample before and after the analysis of client samples. Values must be within the control limits established by the supplier of this sample.

REFERENCE

1. Methods for Chemical Analysis of Water and Wastes, 1983, Environmental Protection Agency, Antimony Method 204.2 (Atomic Absorption, furnace technique).