ISO/PRF 25095-1

ISO/DISPRF 25095-1:2025(en)
ISO/TC 47
Secretariat: JISC
Date: 2025-12-12026-01-13
Propylene oxide for industrial use — —
Part 1:
Determination of purity and trace impurities by gas chromatography
PROOF
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ii
ISO/DISPRF 25095-1:20252026(en)
Contents
Foreword . iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Principle . 1
5 Reagents and materials . 2
6 Apparatus . 3
7 Sampling . 3
8 Procedure . 3
9 Calculation of relative correction factors . 4
10 Calculation of results . 5
11 Expression of results . 5
12 Repeatability and reproducibility . 5
13 Test report . 6
Annex A (informative) Representative chromatograms . 7
Annex B (informative) Reference retention time and relative correction factor for each
component . 13

Foreword . iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Principle . 2
5 Reagents and materials . 2
6 Apparatus . 3
7 Sampling . 3
8 Procedure . 3
9 Calculation of relative correction factors . 4
10 Calculation of results . 5
11 Expression of results . 5
12 Repeatability and reproducibility . 5
13 Test report . 6
Annex A . 7
Annex B . 11

iii
Foreword
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Field Code Changed
iv
DRAFT International Standard ISO/DIS 25095-1:2025(en)

Propylene oxide for industrial use – —
Part 1:
Determination of purity and trace impurities by gas chromatography
WARNING — Persons using this document should be familiar with normal laboratory practice. This
document does not purport to address all the safety problems, if any, associated with its use. It is the
responsibility of the user to establish appropriate safety and health practices.
1 Scope
This document specifies a test method for the determination of propylene oxide and trace impurities in
propylene oxide for industrial use by gas chromatography.
This document is suitable for the determination of propylene oxide with which is produced by
Ethylbenzeneethylbenzene Co-oxidation (PO/SM), Isobutane Co-oxidation (PO/TBA), Cumene Co-oxidation
(CHPPO), Hydrogen Peroxide Oxidation (HPPO) and Chlorohydrin. This document is applicable for
determination of propylene oxide with a purity > 99,7 % and impurity content ≥ 0,000 3 %.
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 760, Determination of water — Karl Fischer method (General method)
ISO 3165:1976, Sampling of chemical products for industrial use — Safety in sampling
ISO 3170:2025, Hydrocarbon liquids—Liquids — Manual sampling
ISO 25095--2, Propylene oxide for industrial use—Part 2: determination of aldehydes by Liquid chromatography
3 Terms and definitions
No terms and definitions are listed in this document.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— — ISO Online browsing platform: available at https://www.iso.org/obphttps://www.iso.org/obp
— — IEC Electropedia: available at https://www.electropedia.org/https://www.electropedia.org/
—
4 Principle
Propylene oxide and impurities in a sample are separated by a gas chromatograph (GC) under propriate
conditions and detected by flame ionization detector (FID). Quantification is achieved by corrected peak-area
normalization, the content of propylene oxide can be calculated after deducting water and total aldehydes,
which are difficult to measure by GC/FID .

5 Reagents and materials
Unless otherwise specified, use only reagents of recognized analytical grade. If there are impurities to be
considered other than those listed as follows, appropriate reagents can be used.
©11)
5.1 5.1 Propylene, CAS No. 115-07-1
5.2 5.2 Methanol solution of dimethyl ether, CAS No. 115-10-6.
5.3 5.3 Methanol, CAS No. 67-56-1.
5.4 5.4 n-Pentane, CAS No. 109-66-0.
5.5 5.5 Acetaldehyde, CAS No. 75-07-0.
5.6 5.6 Ethylene oxide, CAS No. 75-21-8.
5.7 5.7 Methyl formate, CAS No. 107-31-3.
5.8 5.8 Furan, CAS No. 110-00-9.
5.9 5.9 2-Methylpentane, CAS No. 43133-95-5.
5.10 5.10 iso-Propanol, CAS No. 67-63-0.
5.11 5.11 Dimethoxymethane, CAS No. 109-87-5.
5.12 5.12 n-Hexane, CAS No. 110-54-3.
5.13 5.13 Propylene oxide, CAS No. 75-56-9.
5.14 5.14 Propionaldehyde, CAS No. 123-38-6.
5.15 5.15 Acrolein, CAS No. 107-02-8.
5.16 5.16 Acetone, CAS No. 67-64-1.
5.17 5.17 iso-Octane, CAS No. 540-84-1.
5.18 5.18 Benzene, CAS No. 71-43-2.
5.19 5.19 Ethylene glycol monomethyl ether, CAS No. 109-86-4.

1) CAS Registry Number® is a trademark of CAS corporation. This information is given for the convenience of
users of this document and does not constitute an endorsement by ISO of the product named. Equivalent
products may be used if they can be shown to lead to the same results.
1) 1
CAS Registry Number® is a trademark of CAS corporation. This information is given for the convenience of users of
this document and does not constitute an endorsement by ISO of the product named. Equivalent products may be used if
they can be shown to lead to the same results.

2 © ISO /DIS 25095-1 2026 – All rights reserved
ISO/DISPRF 25095-1:20252026(en)
5.20 5.20 1, 2-Dichloropropane, CAS No. 78-87-5.
5.21 5.21 n-Octane, CAS No. 111-65-9.
5.22 5.22 Ethylene glycol, CAS No. 107-21-1.
5.23 5.23 1-Methoxy-2-propanol, CAS No. 107-98-2.
5.24 5.24 1, 2-Propylene glycol, CAS No. 57-55-6.
5.25 5.25 Ethylbenzene, CAS No. 100-41-4.
5.26 5.26 1, 3-Propanediol, CAS No. 504-63-2.
5.27 5.27 iso-Propylbenzen
...