Chapter 5
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Orion AQUAfast Reagent Chemistry Instructions for Orion AquaMate
Thermo Scientific
Orion AquaMate Spectrophotometer User Manual
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113
AC2065 Zinc Tablet Test
Zincon Method
0.02 – 1 mg/l Zn
1.
Load and run the AC2065 method.
2.
Fill a clean AQUAfast 24mm round vial, Cat. No. AC2V24, with 10 ml of deionized water.
Close the vial tightly with the cap. Wipe the exterior of the vial.
3.
Place the vial into the holder in the sample chamber and close the chamber door.
4.
Press the Measure Blank function key to measure the blank.
5.
Empty and dry the vial and then fill the vial with 10 ml of sample.
6.
Add one Copper / Zinc LR Tablet straight from the foil into the vial. Crush the tablet with a
clean stir rod.
7.
Close the vial tightly with the cap and swirl or invert several times until the tablet is
dissolved. Wipe the exterior of the vial.
8.
Wait for a reaction period of 5 minutes.
9.
Place the vial into the holder in the sample chamber and close the chamber door.
10.
Press the Measure Rgnt Blank function key to measure the reagent blank.
11.
Open the sample chamber door and remove the vial from the holder.
12.
Add one EDTA Tablet straight from the foil into the vial. Crush the tablet with a clean stir
rod.
13.
Close the vial tightly with the cap and swirl or invert several times until the tablet is
dissolved. Wipe the exterior of the vial.
14.
Place the vial into the holder in the sample chamber and close the chamber door.
15.
Press the Measure Sample function key to display the result in mg/l zinc.
Notes:
•
Reverse color methods use a reagent that, when prepared with samples, deceases in color
as the concentration of the species being measured in the samples increases. Reverse
color methods require the use of both a blank and a reagent blank. The blank is a clear
solution (deionized water) with zero absorbance. The reagent blank is a mixture of the
reagent and sample (with no EDTA reagent) and provides a zero concentration point with
the darkest color (highest absorbance). The color of samples prepared with the EDTA
reagent will decrease as the concentration increases for this method.
•
Measuring the reagent blank needs to be done with each sample analysis.
•
The tablets must be added in the correct sequence.
•
In the case of high levels of residual chlorine, perform the analysis with a dechlorinated
water sample.