SIST EN ISO 15061:2001

SLOVENSKI STANDARD
SIST EN ISO 15061:2001
01-december-2001
.DNRYRVWYRGH'RORþHYDQMHUD]WRSOMHQHJDEURPDWD0HWRGD]LRQVNR
NURPDWRJUDILMR,62
Water quality - Determination of dissolved bromate - Method by liquid chromatography of
ions (ISO 15061:2001)
Wasserbeschaffenheit - Bestimmung von gelöstem Bromat - Verfahren mittels
Ionenchromatographie (ISO 15061:2001)
Qualité de l'eau - Dosage du bromate dissous - Méthode par chromatographie des ions
en phase liquide (ISO 15061:2001)
Ta slovenski standard je istoveten z: EN ISO 15061:2001
ICS:
13.060.50 3UHLVNDYDYRGHQDNHPLþQH Examination of water for
VQRYL chemical substances
SIST EN ISO 15061:2001 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

---------------------- Page: 1 ----------------------

SIST EN ISO 15061:2001

---------------------- Page: 2 ----------------------

SIST EN ISO 15061:2001
EUROPEAN STANDARD
EN ISO 15061
NORME EUROPÉENNE
EUROPÄISCHE NORM
July 2001
ICS 13.060.01
English version
Water quality - Determination of dissolved bromate - Method by
liquid chromatography of ions (ISO 15061:2001)
Qualité de l'eau - Dosage du bromate dissous - Méthode Wasserbeschaffenheit - Bestimmung von gelöstem Bromat
par chromatographie des ions en phase liquide (ISO - Verfahren mittels Ionenchromatographie (ISO
15061:2001) 15061:2001)
This European Standard was approved by CEN on 28 June 2001.
CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European
Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national
standards may be obtained on application to the Management Centre or to any CEN member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by translation
under the responsibility of a CEN member into its own language and notified to the Management Centre has the same status as the official
versions.
CEN members are the national standards bodies of Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece,
Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: rue de Stassart, 36  B-1050 Brussels
© 2001 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 15061:2001 E
worldwide for CEN national Members.

---------------------- Page: 3 ----------------------

SIST EN ISO 15061:2001
EN ISO 15061:2001 (E)
Foreword
The text of the International Standard ISO 15061:2001 has been prepared by Technical
Committee ISO/TC 147 "Water quality" in collaboration with Technical Committee CEN/TC
230 "Water analysis", the secretariat of which is held by DIN.
This European Standard shall be given the status of a national standard, either by publication
of an identical text or by endorsement, at the latest by January 2002, and conflicting national
standards shall be withdrawn at the latest by January 2002.
According to the CEN/CENELEC Internal Regulations, the national standards organizations of
the following countries are bound to implement this European Standard: Austria, Belgium,
Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy,
Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and the United
Kingdom.
NOTE FROM CMC: The foreword is susceptible to be amended on reception of the German
language version. The confirmed or amended foreword, and when appropriate, the normative
annex ZA for the references to international publications with their relevant European
publications will be circulated with the German version.
Endorsement notice
The text of the International Standard ISO 15061:2001 was approved by CEN as a European
Standard without any modification.
2

---------------------- Page: 4 ----------------------

SIST EN ISO 15061:2001
INTERNATIONAL ISO
STANDARD 15061
First edition
2001-07-01
Water quality — Determination of dissolved
bromate — Method by liquid
chromatography of ions
Qualité de l'eau — Dosage du bromate dissous — Méthode par
chromatographie des ions en phase liquide
Reference number
ISO 15061:2001(E)
©
ISO 2001

---------------------- Page: 5 ----------------------

SIST EN ISO 15061:2001
ISO 15061:2001(E)
PDF disclaimer
This PDF file may contain embedded typefaces. In accordance with Adobe's licensing policy, this file may be printed or viewed but shall not
be edited unless the typefaces which are embedded are licensed to and installed on the computer performing the editing. In downloading this
file, parties accept therein the responsibility of not infringing Adobe's licensing policy. The ISO Central Secretariat accepts no liability in this
area.
Adobe is a trademark of Adobe Systems Incorporated.
Details of the software products used to create this PDF file can be found in the General Info relative to the file; the PDF-creation parameters
were optimized for printing. Every care has been taken to ensure that the file is suitable for use by ISO member bodies. In the unlikely event
that a problem relating to it is found, please inform the Central Secretariat at the address given below.
© ISO 2001
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means, electronic
or mechanical, including photocopying and microfilm, without permission in writing from either ISO at the address below or ISO's member body
in the country of the requester.
ISO copyright office
Case postale 56 � CH-1211 Geneva 20
Tel. + 41 22 749 01 11
Fax + 41 22 749 09 47
E-mail copyright@iso.ch
Web www.iso.ch
Printed in Switzerland
ii © ISO 2001 – All rights reserved

---------------------- Page: 6 ----------------------

SIST EN ISO 15061:2001
ISO 15061:2001(E)
Contents Page
Foreword.iv
Introduction.v
1 Scope .1
2 Normative references .1
3 Interferences .1
4 Principle.2
5 Essential minimum requirements .2
6 Reagents.3
7 Apparatus .4
8 Quality requirements for the separator column .6
9 Sampling and sample pretreatment.8
10 Procedure .10
11 Calculation.12
12 Expression of results .12
13 Test report .12
Annex A (informative) Eluents .13
Annex B (informative) Regeneration solutions .15
Annex C (informative) Example of column-switching technique .16
Annex D (informative) Interlaboratory trial .18
Annex E (informative) Checked interferences.20
Bibliography.21
© ISO 2001 – All rights reserved iii

---------------------- Page: 7 ----------------------

SIST EN ISO 15061:2001
ISO 15061:2001(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO
member bodies). The work of preparing International Standards is normally carried out through ISO technical
committees. Each member body interested in a subject for which a technical committee has been established has
the right to be represented on that committee. International organizations, governmental and non-governmental, in
liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical
Commission (IEC) on all matters of electrotechnical standardization.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 3.
Draft International Standards adopted by the technical committees are circulated to the member bodies for voting.
Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote.
Attention is drawn to the possibility that some of the elements of this International Standard may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights.
International Standard ISO 15061 was prepared by Technical Committee ISO/TC 147, Water quality,
Subcommittee SC 2, Physical, chemical and biochemical methods.
Annexes A, B, C, D and E of this International Standard are for information only.
iv © ISO 2001 – All rights reserved

---------------------- Page: 8 ----------------------

SIST EN ISO 15061:2001
ISO 15061:2001(E)
Introduction
The essential minimum requirements of an ion chromatographic system applied within the scope of this
International Standard for the determination of dissolved bromate are given in clause 5.
The diversity of the appropriate and suitable assemblies, and the procedural steps depending on them, permit a
general description only.
Further information on the analytical technique can be found in the normative references (clause 2) and the
bibliography.
© ISO 2001 – All rights reserved v

---------------------- Page: 9 ----------------------

SIST EN ISO 15061:2001

---------------------- Page: 10 ----------------------

SIST EN ISO 15061:2001
INTERNATIONAL STANDARD ISO 15061:2001(E)
Water quality — Determination of dissolved bromate — Method by
liquid chromatography of ions
1 Scope
This International Standard specifies a method for the determination of dissolved bromate in water (e.g. drinking
water, raw water, surface water, partially treated water or swimming pool water).
Appropriate pretreatment of the sample, for example by elimination of chloride, sulfate, metals, preconcentration or
dilution, gives a range of applicability of 0,5µg/l to 1 000µg/l dissolved bromate.
The working range is restricted by the ion-exchange capacity of any preconcentration columns used and that of the
separator column. Dilution of the sample to the working range may be necessary.
2 Normative references
The following normative documents contain provisions which, through reference in this text, constitute provisions of
this International Standard. For dated references, subsequent amendments to, or revisions of, any of these
publications do not apply. However, parties to agreements based on this International Standard are encouraged to
investigate the possibility of applying the most recent editions of the normative documents indicated below. For
undated references, the latest edition of the normative document referred to applies. Members of ISO and IEC
maintain registers of currently valid International Standards.
ISO 3696:1987, Water for analytical laboratory use — Specification and test methods.
ISO 5667-1:1980, Water quality — Sampling — Part 1: Guidance on the design of sampling programmes.
ISO 5667-2:1991, Water quality — Sampling — Part 2: Guidance on sampling techniques.
ISO 5667-3:1994, Water quality — Sampling — Part 3: Guidance on the preservation and handling of samples.
ISO 8466-1:1990, Water quality — Calibration and evaluation of analytical methods and estimation of performance
characteristics — Part 1: Statistical evaluation of the linear calibration function.
ISO 8466-2:1993, Water quality — Calibration and evaluation of analytical methods and estimation of performance
characteristics — Part 2: Calibration strategy for non-linear second order calibration functions.
3 Interferences
3.1 The presence of nitrate, chloride, carbonate and sulfate may affect the capacity of the concentrator column
and lead to poor recovery of bromate (9.2.1).
3.2 The presence of chloride, sulfate, carbonate and hydrogen carbonate can cause interference with the
determination of bromate (9.2.1). Depending on the column utilized, other ions may interfere; this should be
checked.
3.3 Metals present (e.g. barium and silver ions released from sample pretreatment steps) will bind to the resin
material of concentrator and separator columns, resulting in a loss of performance. Metal ions may be eliminated
with the aid of a metal clean-up column or special exchangers (see Figure 1 and clause 9).
© ISO 2001 – All rights reserved 1

---------------------- Page: 11 ----------------------

SIST EN ISO 15061:2001
ISO 15061:2001(E)
3.4 The interference of some organic acids with the determination of bromate was checked and found not to be
significant to the concentrations tested (annex E).
3.5 Solid particles and organic compounds such as mineral oils, detergents and humic acids shorten the life-time
of the concentrator and separator column.
4Principle
4.1 Sample pretreatment is carried out in order to remove ozone (9.1.3) and solids, and to reduce chloride,
sulfate, carbonate, hydrogen carbonate and metals present by use of cation exchangers (9.2).
4.2 Measurement of bromate is made in the range 0,5µg/l to 1 000µg/l, with or without preconcentration (10.3).
4.3 Liquid chromatographic separation of bromate is carried out either by means of a separator column or after
elution of bromate from a concentrator column, if used. An anion exchange resin is used as the stationary phase,
and usually, aqueous solutions of salts of weak mono- and dibasic acids as eluent (see 6.10 and annex A).
4.4 A conductivity detector (CD) with chemical suppression is used. A UV detector (� = 190 nm to 205 nm) is
suitable to confirm the CD results only.
NOTE When using conductivity detectors it is essential that the eluents have a sufficiently low conductivity. For this reason,
conductivity detectors are combined with a suppressor device (cation exchanger) which reduces the conductivity of the eluent
and transforms the sample species into their respective acids. UV detection measures absorbance directly.
4.5 Strongly retained ions (e.g. nitrate, phosphate, sulfate) are removed from the separator column, e.g. by
flushing the separator column with a more concentrated eluent.
4.6 The concentration of bromate is determined after calibration of the overall procedure.
5 Essential minimum requirements
a) Preconcentration
For low bromate concentrations the use of a concentrator column may be required. On-line techniques can be
used (see 10.3 and annex C). Ensure that recovery is within 80 % to 120 %.
b) Resolution power of the column
It is essential that the peak resolution R shall not fall below 1,3 (clause 8, Figure 4) between bromate and the
nearest peak, which is usually chloride.
c) Method of detection
Measurement of the electrical conductivity (CD) with a chemical suppressor device, and UV if confirmation is
required.
d) Applicability of the method: 0,5µg/l to 1 000µg/l.
e) Calibration shall be carried out in accordance with ISO 8466-1 or ISO 8466-2 (10.2).
f) Guarantee of analytical quality
Control is necessary for the validity of the calibration function (10.5). Replicate determinations may be
necessary. Use of the method of standard addition may be required when matrix interferences are expected
(10.3).
2 © ISO 2001 – All rights reserved

---------------------- Page: 12 ----------------------

SIST EN ISO 15061:2001
ISO 15061:2001(E)
6 Reagents
Use only reagents of recognized analytical grade. Carry out weighing of the reagents with an accuracy of � 1% of
the nominal mass, unless stated otherwise.
6.1 Water, complying with grade 1 as defined in ISO 3696.
6.2 Sodium hydrogen carbonate, NaHCO .
3
6.3 Sodium carbonate,Na CO .
2 3
6.4 Disodium tetraborate decahydrate,Na B O � 10 H O.
2 4 7 2
6.5 Boric acid,H BO .
3 3
6.6 Potassium bromate,KBrO .
3
6.7 Nitric acid, c(HNO )=0,1mol/l.
3
6.8 Sulfuric acid,�(H SO ) = 1,84 g/ml.
2 4
6.9 Ethylenediamine,C H N .
2 8 2
6.10 Eluents.
Degas all water used for eluent preparation. Take steps to avoid any renewed air pick-up during operation (e.g. by
helium sparging). In order to minimize the growth of bacteria or algae, store the eluents in the dark and renew
every 3 d.
See annex A for examples of eluents.
Two different types of eluent are used.
6.10.1 Eluent of Type 1, of a lower concentration level (for examples see clause A.1) to be applicable for the
separation of bromate
and
6.10.2 Eluent of Type 2, of a higher concentration level (for examples see clause A.2) to be applicable to remove
strongly retained ions (e.g. nitrate, phosphate) from the concentrator and separator column.
The choice of eluent is dependent on the choice of column and detector; seek advice from the column supplier.
The chosen combination of separator column and eluent shall conform to the resolution requirements stated in
clause 8.
A selection of reagents for common eluents is presented in 6.2 to 6.5.
�
6.11 Bromate stock standard solution,�(BrO ) = 1 000 mg/l
3
Dry approximately 1,5 g of potassium bromate (6.6) for at least 1 h at 105 °C � 5 °C. Store the dried solid in a
desiccator.
Dissolve 1,306 g � 0,001 g of the dried potassium bromate in approximately 800 ml of water (6.1) in a 1 000 ml
volumetric flask, and dilute to volume with water (6.1). Store the solution at 2 °Cto 6 °C in polyethylene or glass
bottles and renew it every 12 months.
Alternatively, use commercially available stock solutions of the required concentration.
© ISO 2001 – All rights reserved 3

---------------------- Page: 13 ----------------------

SIST EN ISO 15061:2001
ISO 15061:2001(E)
6.12 Bromate standard solutions.
6.12.1 General
Depending upon the concentrations expected, prepare the following standard solutions of different bromate
concentrations from the stock standard solution (6.11). Note the possible risk of changes in concentration caused
by interaction with the vessel material increases with decreasing bromate concentration. Store the standard
solutions in polyethylene or glass bottles.
6.12.2 Bromate Standard Solution I
�
The mass concentration of this solution is �(BrO )=100mg/l.
3
Pipette 10,0 ml of stock standard solution (6.11) into a 100 ml volumetric flask, and dilute to volume with water
(6.1).
Store the solution at 2 °Cto6 °C in polyethylene or glass bottles and renew every 6 months.
6.12.3 Bromate Standard Solution II
�
The mass concentration of this solution is �(BrO )=1mg/l.
3
Pipette 1,0 ml of Standard Solution I (6.12.2) into a 100 ml volumetric flask, dilute to volume with water (6.1).
Store the solution at 2 °Cto6 °C in polyethylene or glass bottles and renew every 3 months.
6.13 Bromate calibration solutions.
Depending on the bromate concentration expected in the sample, use the Bromate Standard Solution I or II (6.12.2
or 6.12.3) to prepare five to ten calibration solutions distributed over the expected working range as evenly as
possible.
�
For example, proceed as follows for the range 0,5µg/l to 5,0µg/l BrO :
3
Pipette, into a series of 100 ml volumetric flasks, the following volumes: 50µl, 100µl, 150µl, 200µl, 250µl, 300µl,
350µl, 400µl, 450µl or 500µl of Bromate Standard Solution II (6.12.3) and dilute to volume with water (6.1).
�
The concentrations of BrO in these calibration solutions are: 0,5µg/l, 1,0µg/l, 1,5µg/l, 2,0µg/l, 2,5µg/l, 3,0µg/l,
3
3,5µg/l, 4,0µg/l, 4,5µg/l and 5,0µg/l respectively.
Prepare the calibration solutions on the day of use.
6.14 Regeneration solutions.
The choice is dependent on the type of metal clean-up columns or suppressor devices. Therefore, follow the
column manufacturer's instructions for the exact composition of the regeneration solutions (for examples of
compositions see annex B).
6.15 Blank solution.
Fill a 100 ml volumetric flask with water (6.1).
7 Apparatus
Usual laboratory apparatus, and, in particular:
4 © ISO 2001 – All rights reserved

---------------------- Page: 14 ----------------------

SIST EN ISO 15061:2001
ISO 15061:2001(E)
7.1 Ion chromatographic system, complying with the quality requirements of clause 8, i.e. resolution. In
general, it shall consist of the following components (see Figure 1):
a) eluent reservoirs, and a degassing unit for two eluents;
b) pump, suitable for step gradient technique;
c) sample delivery device (e.g. sample pump) including a sample injection system incorporating a sample loop of
appropriate volume (e.g. 0,05 ml to 2 ml) or autosampler device;
d) column-switching valves (e.g. 6-port-valve) including a device for timing and controlling valves and pump;
e) concentrator column (may be required for low concentrations);
f) separator column with the specified separating performance (see clause 8);
g) conductivity detector with an anion suppressor device assembly;
h) UV detector (e.g. spectrophotometer: 190 nm to 400 nm);
i) recording device (e.g. recorder, integrator with printer, PC with software for data acquisition and evaluation).
NOTE If a preconcentration step is required, see annex C for an example of a possible system configuration.
7.2 Cartridges.
� cation exchanger in the Ag-form (cartridge);
� cation exchanger in the Ba-form (cartridge);
� cation exchanger in the H-form (cartridge);
� optional: metal clean-up column for on-line use;
� cartridges with non-polar phases to be used for sample preparation (e.g. polyvinylpyrrolidone).
Key
a
Optional.
b
To be recommended for direct injection, when not using a concentrator column (see 10.3, note 1).
Figure 1 — Schematic representation of an ion chromatographic system, including an on-line
preconcentration system
© ISO 2001 – All rights reserved 5

---------------------- Page: 15 ----------------------

SIST EN ISO 15061:2001
ISO 15061:2001(E)
8 Quality requirements for the separator column
Separation conditions shall be such that possible interfering anions do not interfere with bromate. Figures 2 and 3
give examples for different types of water matrix checked.
In chromatograms of samples and standard solutions of bromate, the peak resolution R between bromate and its
nearest peak, usually chloride, shall not fall below 1,3 [see equation (1) and Figure 4].
Key
1 Formate, lactate, propionate, acetate or butyrate 5 Monobromoacetate
2 Valerate or unknown 6 0,8µg/l bromate
3 Unknown 7 Chloride
4 Chlorite
NOTE 1 Verified identification of peaks 6 and 7. Uncertain identification of the other peaks.
NOTE 2 Sample preparation: preconcentration of 2 ml of sample after use of Ag- and H-cartridges according to 9.1.
Figure 2 — Example chromatogram of an ozonylated treated raw water sample prepared conforming
to this International Standard
6 © ISO 2001 – All rights reserved

---------------------- Page: 16 ----------------------

SIST EN ISO 15061:2001
ISO 15061:2001(E)
Key
1 Formate 6 Chlorite
2 Propionate, acetate, or butyrate 7 Unknown
3 Valerate 8 Bromate
4 Unknown 9 Chloride
5 Unknown
NOTE 1 Verified identification of peaks 8 and 9. Uncertain identification of the other peaks.
NOTE 2 Sample preparation: preconcentration of 2 ml of sample after use of Ag- and H-cartridges according to 9.1.
NOTE 3 Elution sequences and retention times (t ) can vary, depending on the type of column and the eluent composition.
R
Figure 3 — Chromatogram of a river sample (River Meuse, sample spiked with 3µg/l bromate) prepared
conforming to this International Standard
© ISO 2001 – All rights reserved 7

---------------------- Page: 17 ----------------------

SIST EN ISO 15061:2001
ISO 15061:2001(E)
Key
1 Peak 1
2 Peak 2
Figure 4 — Graphical representation of the parameters to calculate the peak resolution R
Calculate the peak resolution R using equation (1):
2��tt
��
RR21
R � (1)
2,1
ww�
21
where
R is the resolution for the peak pair 2,1;
2,1
t is the retention time, in seconds, of the first peak;
R1
t is the retention time, in seconds, of the second peak;
R2
w is the peak width, in seconds on the time axis, of the first peak;
1
w is the peak width, in seconds on the time axis, of the second peak.
2
NOTE w , w are the base widths of the isosceles triangles constructed over the Gaussian peaks.
1 2
9 Sampling and sample pretreatment
9.1 General requirements
9.1.1 Sampling and sampling preservation procedures shall be in accordance with ISO 5667-1, ISO 5667-2 and
ISO 5667-3. Treat the calibration solutions (6.13) and the blank solution (6.15) in the same manner as the sample
solution (see Figure 5, steps 1 to 5 and 9.1.3 to 9.2.6).
8 © ISO 2001 – All rights reserved

---------------------- Page: 18 ----------------------

SIST EN ISO 15061:2001
ISO 15061:2001(E)
Figure 5 — Pretreatment steps for samples, calibration and blank solution
9.1.2 Use clean polyethylene vessels for sampling.
9.1.3 Avoid any further formation of bromate after sampling by immediately removing any ozone present. For
example, add 50 mg of ethylenediamine (6.9) to 1 l of sample immediately after sampling (see Figure 5, step 1).
9.1.4 Store the sample in a polyethene vessel at 2 °Cto6 °C until analysis is carried out.
9.2 Elimination of dissolved sulfate, chloride, carbonate, hydrogen carbonate and metals
9.2.1 If considered necessary, remove chloride, sulfate, carbonate and hydrogen carbonate with the aid of the
ion-exchange cartridges described, by carrying out the following elution steps with a constant flowrate of between
1 ml/min and 1,5 ml/min (see Figure 5, steps 2 to 4). Rinse ion-exchange cartridges with water (6.1) before use
according to the manufacturer's instructions. In addition, purge the sample with an inert gas (e.g. N or He) to
2
eliminate carbon dioxide (formed from carbonate and hydrogen carbonate salts).
The presence of nitrate, chloride, carbonate and sulfate may affect the capacity of the concentrator column and
may lead to poor recovery of bromate. This effect should be checked for every matrix by standard addition, and the
recovery of bromate should be in the range 80 % to 120 %.
© ISO 2001 – All rights reserved 9

---------------------- Page: 19 ----------------------

SIST EN ISO 15061:2001
ISO 15061:2001(E)
9.2.2 Prepare the samples as described in 9.1.
9.2.3 Pass approximately 15 ml of the sample through a cation exchanger in the Ba-form (cartridge, 7.2) to
remove dissolved sulfate ions from the sample (see Figure 5, step 2). Discard the first portion of 2 ml.
9.2.4 Pass approximately 10 ml of the remaining sample through a strongly acid cation exchanger in the Ag-form
(cartridge, 7.2) to remove dissolved halides from the sample (see Figure 5, step 3). Discard the first portion of 2 ml.
9.2.5 Pass approximately 8 ml of the remaining sample through a cation exchanger in the H-form (cartridge, 7.2)
to remove dissolved metal ions, carbonate and hydrogen carbonate from the sample (see Figure 5, step 4). Discard
the first portion of 2 ml.
NOTE Alternatively, connect all the clean-up columns/cartridges (see Figure 5, steps 2 to 4). In this case, the first 3 ml of
eluate of the sample leaving the last cartridge should be discarded (see Figure 5, step 4).
9.2.6 Purge the remaining sample for approximately 5 min with an inert gas (e.g. N , He) in order to eliminate
2
carbon dioxide from the sample (see Figure 5, step 5), and analyse the resulting eluate of the sample using the ion
chromatographic system.
10 Procedure
10.1 General
Set up the ion chromatographic system (7.1) according to the instrument manufacturer's instructions.
Run the starting eluent; once the baseline is stable analysis can begin.
If metal clean-up, concentrator columns and suppressor devices are being used, regenerate according to the
instrument manufacturer's instructions before use.
Perform the calibration as described in 10.2. Measure the samples and blank solution (6.15) as described in 10.3.
10.2 Calibration
Inject the pretreated bromate cal
...