MANUAL DE INSTRUCCIONES
CODIGO 80189 REV E
12/2020
Pag.: 51
J
.P. SELECTA s.a.u.
Autovía A-2 Km 585.1 Abrera 08630 (Barcelona) España
Tel 34 937 700 877 Fax 34 937 702 362
e-mail: [email protected] - website: http://www.jpselecta.es
7 Reagents
The reagents to be used must be free of ammonia.
7.1 Prepared reagents
The best thing is to use reagents factory prepared, mainly the HCl for titration. Any
error on its preparation has a direct influence on the result.
As an example, the following reagents could be used, or the equivalent one in
other brands:
•
Boric acid in pounder 99.5%
PANREAC 141015
•
Mixed indicator 4.8 (or 5) RV
PANREAC 283303
(Red of Green Bromocresol)
•
Mixed indicator 4.4 RV
PANREAC 282430
(Red of Blue of Metilene)
•
HCl 0.1N SV
PANREAC 171023
•
HCl 0.25N
SV
PANREAC 182318
•
H
2
SO
4
0.1N
SV
PANREAC 181061
•
H
2
SO
4
0.2N
SV
PANREAC 182011
•
Sodium Hydroxide 40% RE
PANREAC 171220
(For N determination)
•
Acetanilide 99% (Validation standard)
PANREAC 151005
•
Ammonia sulphate (Validation standard)
PANREAC 131140
•
Kjeldahl Catalyst 6.25% Cu tabl. 8g
PANREAC 174428
7.2 Ammonia fixative solution preparation
The preparation of the ammonia fixative solution
is critical
to get a good opera-
tion with PRO-NITRO «A».
This solution must be prepared, working accurately, and using material clean of
strong acids or alkalis.
Note:
- The use of different fixative solutions to the specified ones do not warranty the
equipment good operation.
- Leave the ammonia fixative solution between 24h and 48h before checking,
adjusting and using it.
7.2.1 Preparation for Mixed indicator 4.8 (or 5) (Easy)
Prepare according to this formula for 1 litre of solution:
- Weight 10g of Boric acid (in pounder)
PANREAC 141015
- Solve in 1 litre of distilled water.
- Add 15ml of mixed indicator 5
PANREAC 283303
7.2.2 Preparation for Mixed indicator 4.4
Prepare according to this formula for 1 litre of solution:
- Weight 10g of Boric acid (in pounder)
PANREAC 141015
- Solve in 1 litre of distilled water.
- Add 10ml of mixed indicator 4.4
PANREAC 282430
7.2.3 Preparation for indicator according to ISO 5663
Prepare according to standard ISO 5663 / EN 25663. For water analysis.
Modify on the «CONFIGURATION» menu the following parameters:
•
LS:
Change to value 10
•
Light:
Change to value 10
Note
: If this solution is not prepared with sufficient accuracy, it may be necessary
to adjust the assessment parameters with several tests.
