Thermo Scientific Orion AquaMate UV-Vis, Руководство пользователя

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Chapter 5
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Orion AQUAfast Reagent Chemistry Instructions for Orion AquaMate
76 | Orion AquaMate Spectrophotometer User Manual Thermo Scientific
AC4P29 Copper (Free) Powder Pack Test
Bicinchoninate Method
0.05 – 5 mg/l Cu
1. Load and run the AC4P29 method.
2. Fill a clean AQUAfast 24mm round vial, Cat. No. AC2V24, with 10 ml of sample. 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. Open the sample chamber door and remove the vial from the holder.
6. Add the contents of one Cu 1 F10 Powder Pack straight from the foil into the vial.
7. Close the vial tightly with the cap and swirl or invert several times to mix the contents. Wipe
the exterior of the vial.
8. Wait for a reaction period of 2 minutes.
9. Place the vial into the holder in the sample chamber and close the chamber door.
10. Press the Measure Sample function key to display the result in mg/l free copper.
Notes:
•
For determination of total copper, a digestion is required.
• Extremely acid water samples (pH 2 or less) must be adjusted between pH 4 and pH 6
before the reagent is added (with 8 mol/l potassium hydroxide solution, KOH).
• Accuracy is not affected by undissolved powder.
•
Interferences:
Cyanide (CN
-
) Cyanide prevents full color development. Add 0.2 ml formaldehyde to 10 ml
water sample and wait for a reaction time of 4 minutes (cyanide is masked).
After this perform test as described. Multiply the result by 1.02 to correct the
sample dilution by formaldehyde.
Silver (Ag
+
) If turbidity remains and turns black, silver interference is likely. Add 10 drops of
saturated potassium chloride solution to 75 ml of water sample. Filtrate through
a fine filter. Use 10 ml of the filtered water sample to perform test.