ISO 4907-3:2023

Plastics — Ion exchange resin — Part 3: Determination of exchange capacity of anion exchange resins in hydroxide form

This document specifies test methods of the total exchange capacity, the strong-base group capacity and the weak-base group capacity of the styrene anion exchange resins in hydroxide form.

Plastiques — Résine échangeuse d'ions — Partie 3: Détermination de la capacité d'échange des résines échangeuses d'anions sous forme d'hydroxyde

General Information

• Status: Published
• Publication Date: 17-Apr-2023
• ICS: 83.080.01 - Plastics in general
• Technical Committee: ISO/TC 61/SC 5 - Physical-chemical properties
• Drafting Committee: ISO/TC 61/SC 5/WG 11 - Analytical methods
• Current Stage: 6060 - International Standard published
• Start Date: 18-Apr-2023
• Due Date: 30-Jun-2023
• Completion Date: 18-Apr-2023

Standards Content (Sample)

INTERNATIONAL ISO
STANDARD 4907-3
First edition
2023-04
Plastics — Ion exchange resin —
Part 3:
Determination of exchange capacity
of anion exchange resins in hydroxide
form
Reference number
ISO 4907-3:2023(E)
© ISO 2023

---------------------- Page: 1 ----------------------
ISO 4907-3:2023(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2023
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: [phone]
Email: [e-mail]
Website: www.iso.org
Published in Switzerland
ii
  © ISO 2023 – All rights reserved

---------------------- Page: 2 ----------------------
ISO 4907-3:2023(E)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Principle . 2
5 Reagents . 2
6 Apparatus . 4
7 Samples . 5
7.1 Sampling . 5
7.2 Sample preparation . 5
8 Procedure .6
8.1 General . 6
8.2 Total exchange capacity . 6
8.3 Strong-base group capacity . 6
9 Calculation . 7
9.1 Total exchange capacity . 7
9.2 Strong-base group capacity . 7
9.3 Weak-base group capacity . 8
10 Test report . 8
Annex A (normative) Sampling . 9
Bibliography .11
iii
© ISO 2023 – All rights reserved

---------------------- Page: 3 ----------------------
ISO 4907-3:2023(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.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of ISO document should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).
ISO draws attention to the possibility that the implementation of this document may involve the use
of (a) patent(s). ISO takes no position concerning the evidence, validity or applicability of any claimed
patent rights in respect thereof. As of the date of publication of this document, ISO had not received
notice of (a) patent(s) which may be required to implement this document. However, implementers are
cautioned that this may not represent the latest information, which may be obtained from the patent
database available at www.iso.org/patents. ISO shall not be held responsible for identifying any or all
such patent rights.
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to
the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see
www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 61, Plastics, Subcommittee SC 5, Physical-
chemical properties.
A list of all parts in the ISO 4907 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.
iv
  © ISO 2023 – All rights reserved

---------------------- Page: 4 ----------------------
ISO 4907-3:2023(E)
Introduction
Exchange capacity often determines the performance. In practical use, the anion exchange resin is
usually converted to hydroxide (or amine) form. What is more, from the change of strong-base and
weak-base groups, the degree of pollution and degradation can be judged. This document specifies how
to determine the exchange capacity of anion exchange resins in hydroxide (or amine) form.
v
© ISO 2023 – All rights reserved

---------------------- Page: 5 ----------------------
INTERNATIONAL STANDARD ISO 4907-3:2023(E)
Plastics — Ion exchange resin —
Part 3:
Determination of exchange capacity of anion exchange
resins in hydroxide form
1 Scope
This document specifies test methods of the total exchange capacity, the strong-base group capacity
and the weak-base group capacity of the styrene anion exchange resins in hydroxide form.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 3696, Water for analytical laboratory use — Specification and test methods
ISO 4907-2:2023, Plastics — Ion exchange resin — Part 2: Determination of water content of anion
exchange resins in hydroxide form
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1
hydroxide form styrene anion exchange resin
ionic type of styrene anion exchange resins regenerated by sodium hydroxide solution under the
conditions specified in this document
Note 1 to entry: It is a general term that includes the strong-base groups existing in hydroxide form and the
weak-base groups existing in free amine form.
3.2
total exchange capacity
quantity of active groups in hydroxide form styrene anion exchange resin (3.1) that can exchange with
strong acid under the conditions specified in this document
Note 1 to entry: It is expressed in millimoles per gram or in moles per litre of anion exchange resins.
3.3
strong-base group capacity
quantity of active groups in hydroxide form styrene anion exchange resin (3.1) that can exchange with
neutral salts under the conditions specified in this document
Note 1 to entry: It is expressed in millimoles per gram or in moles per litre of anion exchange resins.
1
© ISO 2023 – All rights reserved

---------------------- Page: 6 ----------------------
ISO 4907-3:2023(E)
4 Principle
When styrene anion exchange resins in hydroxide form reacts with strong acid solution (such as
hydrochloric acid solution), it can exchange active hydroxyls with other anions, and the substituted
hydroxyls will neutralize with hydrions.
The reaction formula is:
CH NCHOH CH NCHCl
() ()
 
2 3 2 3
 
3 3
RR− +→HCl − +HO
 
2
CH NCHH CH NCH HHHCl
 ()  ()
 
223 2 3 2
When styrene anion exchange resins in hydroxide form reacts with neutral salt solution (such as
sodium sulphate solution), it can exchange strong hydroxyls with other anions.
The reaction formula is:
CH NCHOH CH NCHSO
() ()
 
2 3 2 3 4
 3  3
+−
RR− +→Na SO − ++Na OH
 
24
CH NCHH CH NCHHH
 ()  ()
 223  2 3 2
5 Reagents
WARNING — Reagents used in this document may have potential hazards to human health and
the environment. Ensure that the the instructions for the use of reagents are strictly followed.
Unless otherwise indicated, the reagents specified in this document should be analytical grade.
Commercially available, ready-made solutions may be used.
5.1 Water, grade 2 in accordance with ISO 3696.
5.2 Sodium hydroxide, standard solution, c(NaOH) ≈ 0,10 mol/l.
Dissolve 4 g of sodium hydroxide to 1 000 ml with water. Standardize this solution at least weekly as
follows.
5.2.1 Calibration
Dry 10 g of potassium hydrogen phthalate (KHC H O , Guaranteed Reagent) at 105 °C to 110 °C for 4 h.
8 4 4
And then cool to room temperature in a desiccator.
Weigh 0,75 g of potassium hydrogen phthalate (m ) to the nearest 0,00 1 g, and dissolve with 100 ml
1
water in a flask. Add 0,1 ml of phenolphthalein indicator solution. Titrate with 0,10 mol/l sodium
hydroxide solution (5.2) until the pink colour appears and persists for 15 s. Record the consumption
volume of alkali (V ).
1
5.2.2 Blank determination
Pipet 100 ml of water. Carry out a blank determination according to the appropriate procedure 5.2.1.
Record the consumption volume of alkali (V ).
2
5.2.3 Calculation
See Formula (1):
1 000×m
1
c(NaOH)= (1)
204,(220×−VV )
12
...

ISO/FDIS 4907-3:20222023(E)
ISO TC 61/SC 5/WG 11
Date: 2022-112023-01-13
Secretariat: DIN
Plastics — Ion exchange resin — Part 3: Determination of exchange capacity of anion exchange
resins in hydroxide form

---------------------- Page: 1 ----------------------
ISO/FDIS 4907-3:2023(E)
© ISO 20222023
All rights reserved. Unless otherwise specified, or required in the context of its implementation,
no part of this publication may be reproduced or utilized otherwise in any form or by any means,
electronic or mechanical, including photocopying, or posting on the internet or an intranet,
without prior written permission. Permission can be requested from either ISO at the address
below or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: [phone]
Email: [e-mail]
Website: www.iso.org
Published in Switzerland
ii © ISO 2023 – All rights reserved

---------------------- Page: 2 ----------------------
ISO/FDIS 4907-3:2023(E)
Contents
Foreword . iv
Introduction . v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Principle . 2
5 Reagents . 2
6 Apparatus . 4
7 Samples . 5
7.1 Sampling . 5
7.2 Sample preparation . 5
8 Procedure . 6
8.1 Total exchange capacity . 6
8.2 Strong-base group capacity . 6
9 Calculation . 7
9.1 Total exchange capacity . 7
9.2 Strong-base group capacity . 7
9.3 Weak-base group capacity . 8
10 Test Report . 8
Annex A (normative) Sampling . 9

© ISO 2023 – All rights reserved iii

---------------------- Page: 3 ----------------------
ISO/FDIS 4907-3:2023(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.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www.iso.org/patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO’s adherence to the
World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see
www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 61, Plastics, Subcommittee SC 5, Physical-
chemical properties.
A list of all parts in the ISO 4907 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.
iv © ISO 2023 – All rights reserved

---------------------- Page: 4 ----------------------
ISO/FDIS 4907-3:2023(E)
Introduction
Exchange capacity often determines the performance. In practical use, the anion exchange resin is
usually converted to hydroxide (or amine) form. What is more, from the change of strong-base and
weak-base groups, the degree of pollution and degradation can be judged. This document specifies how
to determine the exchange capacity of anion exchange resins in hydroxide (or amine) form.
© ISO 2023 – All rights reserved v

---------------------- Page: 5 ----------------------
FINAL DRAFT INTERNATIONAL STANDARD ISO/FDIS 4907-3:2023(E)

Plastics — Ion exchange resin — Part 3: Determination of
exchange capacity of anion exchange resins in hydroxide form
1 Scope
This document specifies test methods of the total exchange capacity, the strong-base group capacity and
the weak-base group capacity of the styrene anion exchange resins in hydroxide form.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 3696, Water for analytical laboratory use — Specification and test methods
ISO 3696, Water for analytical laboratory use — Specification and test methods
ISO 4907-2:202y2023, Plastics — Ion exchange resin — Part 2: Determination of water content of
anion exchange resins in hydroxide form
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https://www.iso.org/obp
— IEC Electropedia: available at https://www.electropedia.org/
3.1
hydroxide form styrene anion exchange resin
ionic type of styrene anion exchange resins regenerated by sodium hydroxide solution under the
conditions specified in this document
Note 1 to entry: It is a general term that includes the strong-base groups existing in hydroxide form and the
weak-base groups existing in free amine form.
3.2
total exchange capacity
quantity of active groups in hydroxide form styrene anion exchange resin (3.1) that can exchange with
strong acid under the conditions specified in this document
Note 1 to entry: It is expressed in millimoles per gram or in moles per literlitre of anion exchange resins.
3.3
strong-base group capacity
© ISO 2023 – All rights reserved 1

---------------------- Page: 6 ----------------------
ISO/FDIS 4907-3:2023(E)
quantity of active groups in hydroxide form styrene anion exchange resin (3.1) that can exchange with
neutral salts under the conditions specified in this document
Note 1 to entry: It is expressed in millimoles per gram or in moles per literlitre of anion exchange resins.
4 Principle
When styrene anion exchange resins in hydroxide form reacts with strong acid solution (such as
hydrochloric acid solution), it can exchange active hydroxyls with other anions, and the substituted
hydroxyls will neutralize with hydrions.
The reaction formula is:
CH N(CH ) OH CH N(CH ) Cl

23 23
3 3
RR− + HCl→− + H O

2
CH N(CH )H CH N(CH )H HCl

2 3 2 2 3 2
CH N(CH ) OH CH N(CH ) Cl

23 23
3 3
RR− + HCl→− + H O

2
CH N(CH )H CH N(CH )H HCl

2 3 2 2 3 2
When styrene anion exchange resins in hydroxide form reacts with neutral salt solution (such as
sodium sulphate solution), it can exchange strong hydroxyls with other anions.
The reaction formula is:
CH N(CH ) OH CH N(CH ) SO

23 23 4
33
+−
RR− + Na SO →− + Na + OH

24
CH N(CH )H CH N(CH )H

2 3 2 2 3 2
CH N(CH ) OH CH N(CH ) SO

23 23 4
33
+−
RR− + Na SO →− + Na + OH

24
CH N(CH )H CH N(CH )H

2 3 2 2 3 2
5 Reagents
WARNING — Reagents used in this document may have potential hazards to human health and the
environment. Please strictly followEnsure that the the instructions for the use of reagents are strictly
followed.
Unless otherwise indicated, the reagents specified in this document should be analytical grade.
Commercially available, ready-made solutions may be used.
5.1 Water, grade 2 in accordance with ISO 3696.
5.2 Sodium hydroxide, standard solution, c(NaOH) ≈ 0,10 mol/l.
Dissolve 4 g of sodium hydroxide to 1 000 ml with water. Standardize this solution at least weekly as
follows.
5.2.1 Calibration
Dry 10 g of potassium hydrogen phthalate (KHC H O , Guaranteed Reagent) at 105 °C to 110 °C for
8 4 4
4 h. And then cool to room temperature in a desiccator.
2 © ISO 2023 – All rights reserved

---------------------- Page: 7 ----------------------
ISO/FDIS 4907-3:2023(E)
Weigh 0,75 g of potassium hydrogen phthalate (m ) to the nearest 0,00 1 g, and dissolve with 100 ml
1
water in a flask. Add 0,1 ml of phenolphthalein indicator solution. Titrate with 0,10 mol/l sodium
hydroxide solution (5.2) until the pink colour appears and persists for 15 s. Record the consumption
volume of alkali (V ).
1
5.2.2 Blank determination
Pipet 100 ml of water. Carry out a blank determination according to the appropriate procedure 5.2.1.
Record the consumption volume of alkali (V ).
2
5.2.3 Calculation
See Formula (1):
1 000×m 1 000×m
1 1
c(NaOH)= c(NaOH)=
(1)
204,220×(VV− ) 204,220×−(VV )
12 1 2
where
 c(NaOH) is the actual concentration, expressed in moles per litre (mol/l), of the sodium hydroxid
solution;
 m is the mass, expressed in grams (g), of potassium hydrogen phthalate;
1
 V is the titration consumption volume, expressed in millilitres (ml), of the sodium
1
hydroxide solution;
 V is the blank consumption volume, expressed in millilitres (ml), of the sodium hydroxide
2
solution.
5.3 Hydrochloric acid, standard solution, c(HCl) ≈ 0,10 mol/l.
Dilute 9 ml of hydrochloric acid (1,19 g/ml) to 1 000 ml with water. Calibrate this solution at least
weekly as follows.
5.3.1 Calibration
Dry 5 g of sodium carbonate (Na CO , Guaranteed Reagent) at 270 °C to 300 °C for 4 h. And then cool to
2 3
room temperature in a desiccator.
Weigh 0,2
...

FINAL
INTERNATIONAL ISO/FDIS
DRAFT
STANDARD 4907-3
ISO/TC 61/SC 5
Plastics — Ion exchange resin —
Secretariat: DIN
Voting begins on:
Part 3:
2023-01-30
Determination of exchange capacity
Voting terminates on:
of anion exchange resins in hydroxide
2023-03-27
form
RECIPIENTS OF THIS DRAFT ARE INVITED TO
SUBMIT, WITH THEIR COMMENTS, NOTIFICATION
OF ANY RELEVANT PATENT RIGHTS OF WHICH
THEY ARE AWARE AND TO PROVIDE SUPPOR TING
DOCUMENTATION.
IN ADDITION TO THEIR EVALUATION AS
Reference number
BEING ACCEPTABLE FOR INDUSTRIAL, TECHNO-
ISO/FDIS 4907-3:2023(E)
LOGICAL, COMMERCIAL AND USER PURPOSES,
DRAFT INTERNATIONAL STANDARDS MAY ON
OCCASION HAVE TO BE CONSIDERED IN THE
LIGHT OF THEIR POTENTIAL TO BECOME STAN-
DARDS TO WHICH REFERENCE MAY BE MADE IN
NATIONAL REGULATIONS. © ISO 2023

---------------------- Page: 1 ----------------------
ISO/FDIS 4907-3:2023(E)
FINAL
INTERNATIONAL ISO/FDIS
DRAFT
STANDARD 4907-3
ISO/TC 61/SC 5
Plastics — Ion exchange resin —
Secretariat: DIN
Voting begins on:
Part 3:
Determination of exchange capacity
Voting terminates on:
of anion exchange resins in hydroxide
form
COPYRIGHT PROTECTED DOCUMENT
© ISO 2023
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
or ISO’s member body in the country of the requester.
RECIPIENTS OF THIS DRAFT ARE INVITED TO
ISO copyright office
SUBMIT, WITH THEIR COMMENTS, NOTIFICATION
OF ANY RELEVANT PATENT RIGHTS OF WHICH
CP 401 • Ch. de Blandonnet 8
THEY ARE AWARE AND TO PROVIDE SUPPOR TING
CH-1214 Vernier, Geneva
DOCUMENTATION.
Phone: [phone]
IN ADDITION TO THEIR EVALUATION AS
Reference number
Email: [e-mail]
BEING ACCEPTABLE FOR INDUSTRIAL, TECHNO-
ISO/FDIS 4907-3:2023(E)
Website: www.iso.org
LOGICAL, COMMERCIAL AND USER PURPOSES,
DRAFT INTERNATIONAL STANDARDS MAY ON
Published in Switzerland
OCCASION HAVE TO BE CONSIDERED IN THE
LIGHT OF THEIR POTENTIAL TO BECOME STAN-
DARDS TO WHICH REFERENCE MAY BE MADE IN
ii
  © ISO 2023 – All rights reserved
NATIONAL REGULATIONS. © ISO 2023

---------------------- Page: 2 ----------------------
ISO/FDIS 4907-3:2023(E)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Principle . 2
5 Reagents . 2
6 Apparatus . 4
7 Samples . 5
7.1 Sampling . 5
7.2 Sample preparation . 5
8 Procedure .6
8.1 General . 6
8.2 Total exchange capacity . 6
8.3 Strong-base group capacity . 6
9 Calculation . 6
9.1 Total exchange capacity . 6
9.2 Strong-base group capacity . 7
9.3 Weak-base group capacity . 8
10 Test Report .8
Annex A (normative) Sampling . 9
Bibliography .11
iii
© ISO 2023 – All rights reserved

---------------------- Page: 3 ----------------------
ISO/FDIS 4907-3:2023(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.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www.iso.org/patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO’s adherence to
the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see
www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 61, Plastics, Subcommittee SC 5, Physical-
chemical properties.
A list of all parts in the ISO 4907 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.
iv
  © ISO 2023 – All rights reserved

---------------------- Page: 4 ----------------------
ISO/FDIS 4907-3:2023(E)
Introduction
Exchange capacity often determines the performance. In practical use, the anion exchange resin is
usually converted to hydroxide (or amine) form. What is more, from the change of strong-base and
weak-base groups, the degree of pollution and degradation can be judged. This document specifies how
to determine the exchange capacity of anion exchange resins in hydroxide (or amine) form.
v
© ISO 2023 – All rights reserved

---------------------- Page: 5 ----------------------
FINAL DRAFT INTERNATIONAL STANDARD ISO/FDIS 4907-3:2023(E)
Plastics — Ion exchange resin —
Part 3:
Determination of exchange capacity of anion exchange
resins in hydroxide form
1 Scope
This document specifies test methods of the total exchange capacity, the strong-base group capacity
and the weak-base group capacity of the styrene anion exchange resins in hydroxide form.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 3696, Water for analytical laboratory use — Specification and test methods
ISO 4907-2:2023, Plastics — Ion exchange resin — Part 2: Determination of water content of anion
exchange resins in hydroxide form
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1
hydroxide form styrene anion exchange resin
ionic type of styrene anion exchange resins regenerated by sodium hydroxide solution under the
conditions specified in this document
Note 1 to entry: It is a general term that includes the strong-base groups existing in hydroxide form and the
weak-base groups existing in free amine form.
3.2
total exchange capacity
quantity of active groups in hydroxide form styrene anion exchange resin (3.1) that can exchange with
strong acid under the conditions specified in this document
Note 1 to entry: It is expressed in millimoles per gram or in moles per litre of anion exchange resins.
3.3
strong-base group capacity
quantity of active groups in hydroxide form styrene anion exchange resin (3.1) that can exchange with
neutral salts under the conditions specified in this document
Note 1 to entry: It is expressed in millimoles per gram or in moles per litre of anion exchange resins.
1
© ISO 2023 – All rights reserved

---------------------- Page: 6 ----------------------
ISO/FDIS 4907-3:2023(E)
4 Principle
When styrene anion exchange resins in hydroxide form reacts with strong acid solution (such as
hydrochloric acid solution), it can exchange active hydroxyls with other anions, and the substituted
hydroxyls will neutralize with hydrions.
The reaction formula is:
CH NCHOH CH NCHCl
() ()
 
2 3 2 3
 
3 3
RR− +→HCl − +HO
 
2
CH NCHH CH NCH HHHCl
 ()  ()
 
223 2 3 2
When styrene anion exchange resins in hydroxide form reacts with neutral salt solution (such as
sodium sulphate solution), it can exchange strong hydroxyls with other anions.
The reaction formula is:
CH NCHOH CH NCHSO
() ()
 
2 3 2 3 4
 3  3
+−
RR− +→Na SO − ++Na OH
 
24
CH NCHH CH NCHHH
 ()  ()
 223  2 3 2
5 Reagents
WARNING — Reagents used in this document may have potential hazards to human health and
the environment. Ensure that the the instructions for the use of reagents are strictly followed.
Unless otherwise indicated, the reagents specified in this document should be analytical grade.
Commercially available, ready-made solutions may be used.
5.1 Water, grade 2 in accordance with ISO 3696.
5.2 Sodium hydroxide, standard solution, c(NaOH) ≈ 0,10 mol/l.
Dissolve 4 g of sodium hydroxide to 1 000 ml with water. Standardize this solution at least weekly as
follows.
5.2.1 Calibration
Dry 10 g of potassium hydrogen phthalate (KHC H O , Guaranteed Reagent) at 105 °C to 110 °C for 4 h.
8 4 4
And then cool to room temperature in a desiccator.
Weigh 0,7
...