Bante Instruments 221 User Manual

ORP I 18
(3) If the platinum sensing element is severely contaminated, polish
the platinum surface gently with an abrasive paper of 600 grid.
Place the electrode in 0.1M HCl solution for 10 minutes. Remove
and rinse with distilled water, then soak in 4M KCl solution for
at least 6 hours.
If the electrode does not restore normal performance, replace
the electrode.
Storing the ORP Electrode
If you do not use the electrode for long periods, store the electrode in
4M KCl solution or storage solution.
Appendix
Preparation of ORP Standard Solutions
Quinhydrone solution A: Dissolve 3 grams of quinhydrone reagent in
500 ml of the pH 4.01 buffer solution, stir the solution for 10 minutes.
Undissolved quinhydrone reagent must be present. If necessary, add
the reagent.
Temperature
Potential (± 10 mV)
20° C
268 mV
25°C
263 mV
30° C
260 mV
Quinhydrone solution B: Dissolve 3 grams of quinhydrone reagent in
500 ml of the pH 7.00 buffer solution, stir the solution for 10 minutes.
Undissolved quinhydrone reagent must be present. If necessary, add
the reagent.
Temperature
Potential (± 10 mV)
20° C
94 mV
25°C
87 mV
30° C
80 mV
Due to the quinhydrone solution is susceptible to air oxidation in
storage, make sure to prepare the fresh solution before use.
Preparation of Electrode Storage Solution
• Dissolve 29.8 grams of analytical grade potassium chloride (KCl)
reagent in 100 ml distilled water.
• Add pH 4.01 standard buffer and adjust solution to pH 4.
Platinum sensing element

Bante Instruments 221 Specifications

General

Brand	Bante Instruments
Model	221
Category	Measuring Instruments
Language	English