CEN/TS 17789-1:2022

SLOVENSKI STANDARD
01-februar-2023
Organsko-mineralna gnojila - Identifikacija sredstev za kelatiranje - 1. del:
Določevanje EDTA, HEEDTA in DTPA z ionsko kromatografijo
Organo-mineral fertilizers - Identification of chelating agents - Part 1: Determination of
EDTA, HEEDTA and DTPA by ion chromatography
Organisch-mineralische Düngemittel - Identifizierung von Chelatbildnern - Teil 1:
Bestimmung von EDTA, HEEDTA und DTPA mittels Ionenchromatographie
Engrais organo-minéraux - Identification des agents chélatants - Partie 1 : Détermination
de l'EDTA, de l'HEEDTA et du DTPA par chromatographie ionique
Ta slovenski standard je istoveten z: CEN/TS 17789-1:2022
ICS:
65.080 Gnojila Fertilizers
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

CEN/TS 17789-1
TECHNICAL SPECIFICATION
SPÉCIFICATION TECHNIQUE
April 2022
TECHNISCHE SPEZIFIKATION
ICS 65.080
English Version
Organo-mineral fertilizers - Identification of chelating
agents - Part 1: Determination of EDTA, HEEDTA and
DTPA by ion chromatography
Engrais organo-minéraux - Identification des agents Organisch-mineralische Düngemittel - Identifizierung
chélatants - Partie 1 : Détermination de l'EDTA, de von Chelatbildnern - Teil 1: Bestimmung von EDTA,
l'HEEDTA et du DTPA par chromatographie ionique HEEDTA und DTPA mittels Ionenchromatographie
This Technical Specification (CEN/TS) was approved by CEN on 21 February 2022 for provisional application.

The period of validity of this CEN/TS is limited initially to three years. After two years the members of CEN will be requested to
submit their comments, particularly on the question whether the CEN/TS can be converted into a European Standard.

CEN members are required to announce the existence of this CEN/TS in the same way as for an EN and to make the CEN/TS
available promptly at national level in an appropriate form. It is permissible to keep conflicting national standards in force (in
parallel to the CEN/TS) until the final decision about the possible conversion of the CEN/TS into an EN is reached.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and
United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2022 CEN All rights of exploitation in any form and by any means reserved Ref. No. CEN/TS 17789-1:2022 E
worldwide for CEN national Members.

Contents Page
European foreword . 3
Introduction . 4
1 Scope . 5
2 Normative references . 5
3 Terms and definitions . 5
4 Principle . 5
5 Interferences . 5
6 Reagents . 6
7 Apparatus . 7
8 Sampling and sample preparation . 8
9 Procedure . 8
9.1 Preparation of the test solution . 8
9.2 Preparation of the standard solutions . 8
9.3 Chromatographic analysis . 8
10 Expression of results . 9
11 Test report . 9
Annex A (informative) Complete names of chelating agents . 10
Annex B (informative) Chromatogram . 11
Bibliography . 12

European foreword
This document (CEN/TS 17789-1:2022) has been prepared by Technical Committee CEN/TC 260
“Fertilizers and liming materials”, the secretariat of which is held by DIN.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
This document has been prepared under a Standardization Request given to CEN by the European
Commission and the European Free Trade Association.
Any feedback and questions on this document should be directed to the users’ national standards body.
A complete listing of these bodies can be found on the CEN website.
According to the CEN/CENELEC Internal Regulations, the national standards organisations of the
following countries are bound to announce this Technical Specification: Austria, Belgium, Bulgaria,
Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland,
Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of
North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United
Kingdom.
Introduction
Micronutrients are considered to be, in plant nutrition, a number of elements known to be needed in
small amounts for proper plant growth and development. The most common are Iron (Fe), Manganese
(Mn), Molybdenum (Mo), Copper (Cu), Zinc (Zn) and Boron (B).
If an organo-mineral fertilizer contains a substance, or one of the substances in the mixture, which is
intended to enhance the long term availability to plants of micronutrients in the EU fertilizing product,
that substance is either a chelating agent or a complexing agent.
The chelating agents are divided into two groups :
— Group 1: EDTA, DTPA, HEEDTA, IDHA and [S,S]-EDDS;
— Group 2: Chelating agents present in UVCB (unknown or variable composition, complex reaction
products or biological materials) chelates including [o,o] EDDHA, [o,p] EDDHA, [o,o] EDDHMA, HBED
and EDDHSA.
This document specifies the test method to be used in order to determine the content of certain chelating
agents (EDTA, DTPA and HEEDTA) in organo-mineral fertilizers (product function category (PFC) 1(B)
according to Regulation (EU) 2019/1009 [4]).

Abbreviated terms are described in Annex A.
1 Scope
This document specifies a method for the determination by ion chromatography of the total amount of
each of the individual chelating agents EDTA, HEEDTA, and DTPA in organo-mineral fertilizers, having an
organic matrix based on vegetal residues (cocoa shells, grape residue, soybean residue, …), algae extract,
and animal meal (feather, bones, blood, .) and containing one or more of these substances.
The method allows the identification and the determination of the total water-soluble fraction of each of
these chelating agents. It does not allow to distinguish between the free form and the metal bound form
of the chelating agents.
This method applies to organo-mineral fertilizers containing chelates of one or more of the following
micronutrients: cobalt, copper, iron, manganese, zinc and with a mass fraction of at least 0,1 %.
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.
EN 12944-1, Fertilizers and liming materials — Vocabulary — Part 1: General terms
EN 12944-2, Fertilizers and liming materials — Vocabulary — Part 2: Terms relating to fertilizers
3 Terms and definitions
For the purposes of this document, the terms and definitions given in EN 12944-1 and EN 12944-2 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/
4 Principle
The micronutrients associated with the chelating agents present in an aqueous extract of the sample are
replaced by iron(III). The iron chelates are separated and determined by ion chromatography. The
separation is based on anion exchange, by elution with a nitrate acetate solution. The detection is based
on UV photometry at 330 nm, after post-column reaction with diluted perchloric acid.
5 Interferences
Several substances can interfere, to a degree largely dependent on the type of column used. With the
column described in 7.2, the following phenomena have been observed.
a) Injection of solutions having high concentrations of salts can cause shifts in the retention times,
mostly decreasing the retention when compared to the standard solutions. In these cases, the identity
of the peaks can be confirmed by standard addition.
b) Solutions having high concentrations of salts can also create a large signal at the void volume, poorly
resolved from the HEEDTA peak.
c) High concentrations of nitrate, carbonate, sulfate, and phosphate do not interfere. However, large
amounts of chloride create a negative fronting peak poorly resolved from the DTPA peak and altering
its peak shape.
d) Compounds, related to the group of polyamino polycarboxylic acids can interfere. While signals for
[o,o] EDDHA, [o,o] EDDHMA, and EDDHSA are not detected, relatively weak signals are observed for
NTA and CDTA. Under some conditions NTA can coelute with HEEDTA or EDTA.
e) No signals have been detected for the following complexing agents: citrate, oxalate, tartrate,
phthalate, and 20 naturally occurring amino acids.
6 Reagents
All reagents shall be of recognized analytical grade.
6.1 Water
All water used should conform to EN ISO 3696 and be degassed.
6.2 Nitric acid, substance concentration c(HNO ) = 7,2 mol/l.
Nitric acid, diluted 1 + 1 with water.
6.3 Sodium hydroxide solution, c(NaOH) = 0,5 mol/l.
Dissolve 20 g of NaOH in pellet form in a 1 000 ml volumetric flask with water. Dilute to the mark and
homogenize.
6.4 EDTA stock solution, c(EDTA) = 2 mmol/l.
Dissolve 372 mg of the disodium dihydrogen salt of ethylene diamine tetraacetic acid dihydrate in 400 ml
of water in a 500 ml volumetric flask. After dissolution, dilute to the mark with water and homogenize.
Store the solution in a plastic bottle.
6.5 HEEDTA stock solution, c(HEEDTA) = 2 mmol/l.
Dissolve 380 mg of the trisodium salt of hydroxyethyl ethylene diamine triacetic acid dihydrate in 400 ml
of water in a 500 ml volumetric flask. After dissolution, dilute to the mark with water and homogenize.
Store the solution in a plastic bottle.
6.6 DTPA stock solution, c(DTPA) = 2 mmol/l.
Dissolve 393 mg of diethylene triamine pentaacetic acid in 10 ml of NaOH (6.3) in a 50 ml beaker. After
dissolution, transfer quantitatively into a 500 ml volumetric flask, dilute to the mark with water and
homogenize. Store the solution in a plastic bottle.
6.7 EDTA/HEEDTA/DTPA standard mixtures.
Into a set of three volumetric flasks of 100 ml, pipette respectively 2,5 ml, 5 ml and 10 ml of each stock
solution of 2 mmol/l (6.4, 6.5 and 6.6). Dilute to the mark with water and homogenize. These solutions
contain a mixture of EDTA, HEEDTA and DTPA, in concentrations of respectively 0,05 mmol/l, 0,1 mmol/l
and 0,2 mmol/l. They should be used within two days.
6.8 Eluent nitrate (50 mmol/l) and acetate (50 mmol/l).
Dissolve 4,10 g of anhydrous sodium acetate (NaCH COO) in a mixture of 800 ml of water and 6,95 ml of
nitric acid (6.2) in a 1 l volumetric flask. Dilute to the mark with water and homogenize. Adjust the pH of
the eluent to 2,75 ± 0,20. Before use, filter the solution through a 0,45 µm membrane filter (7.4).
NOTE The concentration of the eluent influences the speed and the efficiency of the separation, which can be
carried out with eluent concentrations varying between 25 mmol/l and 75 mmol/l of nitrate and acetate. At low
concentrations, an improved separation between the void signal, the HEEDTA and the EDTA peaks can be obtained,
while at high concentrations a better DTPA peak shape is observed.
...