ASTM E203-16

Standard Test Method for Water Using Volumetric Karl Fischer Titration

SIGNIFICANCE AND USE
4.1 Titration techniques using KF reagent are one of the most widely used for the determination of water.  
4.2 Although the volumetric KF titration can determine low levels of water, it is generally accepted that coulometric KF titrations (see Test Method E1064) are more accurate for routine determination of very low levels of water. As a general rule, if samples routinely contain water concentrations of 500 mg/kg or less, the coulometric technique should be considered.  
4.3 Applications can be subdivided into two sections: (1) organic and inorganic compounds, in which water may be determined directly, and (2) compounds, in which water cannot be determined directly, but in which interferences may be eliminated by suitable chemical reactions or modifications of the procedure. Further discussion of interferences is included in Section 5 and Appendix X2.  
4.4 Water can be determined directly in the presence of the following types of compounds:    
Organic Compounds  
Acetals  
Ethers  
Acids (Note 1)  
Halides  
Acyl halides  
Hydrocarbons (saturated and unsaturated)  
Alcohols  
Ketones, stable (Note 4)  
Aldehydes, stable (Note 2)  
Nitriles  
Amides  
Orthoesters  
Amines, weak (Note 3)  
Peroxides (hydro, dialkyl)  
Anhydrides  
Sulfides  
Disulfides  
Thiocyanates  
Esters  
Thioesters  
Inorganic Compounds  
Acids (Note 5)  
Cupric oxide  
Acid oxides (Note 6)  
Desiccants  
Aluminum oxides  
Hydrazine sulfate  
Anhydrides  
Salts of organic and inorganic acids (Note 6)  
Barium dioxide  
Calcium carbonate  
Note 1: Some acids, such as formic, acetic, and adipic acid, are slowly esterified. For high accuracy with pyridine-based reagents, use 30 to 50 % pyridine in methanol as the solvent. When using pyridine-free reagents, commercially available buffer solutions can be added to the sample prior to titration. With formic acid, it may be necessary to use methanol-free solvents and titrants (1).4
No...
SCOPE
1.1 This test method is intended as a general guide for the application of the volumetric Karl Fischer (KF) titration for determining free water and water of hydration in most solid or liquid organic and inorganic compounds. This test method is designed for use with automatic titration systems capable of determining the KF titration end point potentiometrically; however, a manual titration method for determining the end point visually is included as Appendix X1. Samples that are gaseous at room temperature are not covered (see Appendix X4). This test method covers the use of both pyridine and pyridine-free KF reagents for determining water by the volumetric titration. Determination of water using KF coulometric titration is not discussed. By proper choice of the sample size, KF reagent concentration and apparatus, this test method is suitable for measurement of water over a wide concentration range, that is, parts per million to pure water.  
1.2 The values stated in SI units are to be regarded as standard.  
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. Specific warnings are given in 3.1 and 7.3.3.  
1.4 Review the current Safety Data Sheets (SDS) for detailed information concerning toxicity, first aid procedures, and safety precautions for chemicals used in this test procedure.

General Information

• Status: Historical
• Publication Date: 31-Mar-2016
• ICS: 71.040.40 - Chemical analysis
• Technical Committee: D16 - Aromatic, Industrial, Specialty and Related Chemicals
• Drafting Committee: D16.04 - Instrumental Analysis

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: E203 − 16
Standard Test Method for
1
Water Using Volumetric Karl Fischer Titration
This standard is issued under the fixed designation E203; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
This standard has been approved for use by agencies of the U.S. Department of Defense.
1. Scope* 2. Referenced Documents
2.1 A list of existing ASTM Karl Fischer methods, their
1.1 This test method is intended as a general guide for the
applications to various products, and the sponsoring commit-
application of the volumetric Karl Fischer (KF) titration for
tees is given in Appendix X3.
determining free water and water of hydration in most solid or
2
liquid organic and inorganic compounds. This test method is
2.2 ASTM Standards:
designed for use with automatic titration systems capable of
D789 Test Methods for Determination of Solution Viscosi-
determining the KF titration end point potentiometrically;
ties of Polyamide (PA)
however, a manual titration method for determining the end
D803 Test Methods for Testing Tall Oil
point visually is included as Appendix X1. Samples that are
D890 Test Method for Water in Liquid Pine Chemicals
gaseous at room temperature are not covered (see Appendix
D1123 Test Methods for Water in Engine Coolant Concen-
X4). This test method covers the use of both pyridine and
trate by the Karl Fischer Reagent Method
pyridine-free KF reagents for determining water by the volu-
D1152 Specification for Methanol (Methyl Alcohol)
metric titration. Determination of water using KF coulometric
D1193 Specification for Reagent Water
titration is not discussed. By proper choice of the sample size,
D1348 Test Methods for Moisture in Cellulose (Withdrawn
3
KF reagent concentration and apparatus, this test method is
2017)
suitable for measurement of water over a wide concentration
D1364 Test Method for Water in Volatile Solvents (Karl
range, that is, parts per million to pure water.
Fischer Reagent Titration Method)
D1533 Test Method for Water in Insulating Liquids by
1.2 The values stated in SI units are to be regarded as
Coulometric Karl Fischer Titration
standard.
D1568 Test Methods for Sampling and Chemical Analysis of
1.3 This standard does not purport to address all of the
Alkylbenzene Sulfonates
safety concerns, if any, associated with its use. It is the
D1631 Test Method for Water in Phenol and Related Mate-
responsibility of the user of this standard to establish appro-
rials by the Iodine Reagent Method
priate safety, health, and environmental practices and deter-
D2072 Test Method for Water in Fatty Nitrogen Compounds
mine the applicability of regulatory limitations prior to use.
3
(Withdrawn 2007)
Specific warnings are given in 3.1 and 7.3.3.
D2575 Methods of Testing Polymerized Fatty Acids (With-
1.4 Review the current Safety Data Sheets (SDS) for de- 3
drawn 2007)
tailed information concerning toxicity, first aid procedures, and
D3277 Test Methods for Moisture Content of Oil-
safety precautions for chemicals used in this test procedure. 3
Impregnated Cellulosic Insulation (Withdrawn 2010)
1.5 This international standard was developed in accor- D3401 Test Methods for Water in Halogenated Organic
dance with internationally recognized principles on standard- Solvents and Their Admixtures
ization established in the Decision on Principles for the
D4017 Test Method for Water in Paints and Paint Materials
Development of International Standards, Guides and Recom- by Karl Fischer Method
mendations issued by the World Trade Organization Technical D4377 Test Method for Water in Crude Oils by Potentiomet-
Barriers to Trade (TBT) Committee. ric Karl Fischer Titration
1 2
This test method is under the jurisdiction of ASTM Committee D16 on For referenced ASTM standards, visit the ASTM website, www.astm.org, or
Aromatic, Industrial, Specialty and Related Chemicals and is the direct responsi- contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
bility of Subcommittee D16.04 on Instrumental Analysis. Standards volume information, refer to the standard’s Document Summary page on
Current edition approved April 1, 2016. Published May 2016. Originally the ASTM website.
3
approved in 1962 as E203 – 62 T. Last previous edition approved in 2008 as The last approved version of this historical standard is referenced on
E203 – 08. DOI: 10.1520/E0203-16. www.astm.org.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

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...

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: E203 − 08 E203 − 16
Standard Test Method for
1
Water Using Volumetric Karl Fischer Titration
This standard is issued under the fixed designation E203; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
This standard has been approved for use by agencies of the U.S. Department of Defense.
1. Scope*
1.1 This test method is intended as a general guide for the application of the volumetric Karl Fischer (KF) titration for
determining free water and water of hydration in most solid or liquid organic and inorganic compounds. This test method is
designed for use with automatic titration systems capable of determining the KF titration end point potentiometrically; however,
a manual titration method for determining the end point visually is included as Appendix X1. Samples that are gaseous at room
temperature are not covered (see Appendix X4). This test method covers the use of both pyridine and pyridine-free KF reagents
for determining water by the volumetric titration. Determination of water using KF coulometric titration is not discussed. By proper
choice of the sample size, KF reagent concentration and apparatus, this test method is suitable for measurement of water over a
wide concentration range, that is, parts per million to pure water.
1.2 The values stated in SI units are to be regarded as standard.
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility
of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory
limitations prior to use. Specific warnings are given in 3.1 and 7.3.3.
1.4 Review the current Material Safety Data Sheets (MSDS)(SDS) for detailed information concerning toxicity, first aid
procedures, and safety precautions for chemicals used in this test procedure.
2. Referenced Documents
2.1 A list of existing ASTM Karl Fischer methods, their applications to various products, and the sponsoring committees is
given in Appendix X3.
2
2.2 ASTM Standards:
D789 Test Methods for Determination of Solution Viscosities of Polyamide (PA)
D803 Test Methods for Testing Tall Oil
D890 Test Method for Water in Liquid Pine Chemicals
D1123 Test Methods for Water in Engine Coolant Concentrate by the Karl Fischer Reagent Method
D1152 Specification for Methanol (Methyl Alcohol)
D1193 Specification for Reagent Water
D1348 Test Methods for Moisture in Cellulose
D1364 Test Method for Water in Volatile Solvents (Karl Fischer Reagent Titration Method)
D1533 Test Method for Water in Insulating Liquids by Coulometric Karl Fischer Titration
D1568 Test Methods for Sampling and Chemical Analysis of Alkylbenzene Sulfonates
D1631 Test Method for Water in Phenol and Related Materials by the Iodine Reagent Method
3
D2072 Test Method for Water in Fatty Nitrogen Compounds (Withdrawn 2007)
3
D2575 Methods of Testing Polymerized Fatty Acids (Withdrawn 2007)
3
D3277 Test Methods for Moisture Content of Oil-Impregnated Cellulosic Insulation (Withdrawn 2010)
D3401 Test Methods for Water in Halogenated Organic Solvents and Their Admixtures
1
This test method is under the jurisdiction of ASTM Committee E15 on Industrial and Specialty Chemicals and is the direct responsibility of Subcommittee E15.01 on
General Standards.
Current edition approved Oct. 1, 2008April 1, 2016. Published November 2008May 2016. Originally approved in 1962 as E203 – 62 T. Last previous edition approved
in 20012008 as E203 – 01.E203 – 08. DOI: 10.1520/E0203-08.10.1520/E0203-16.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
3
The last approved version of this historical standard is referenced on www.astm.org.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

---------------------- Page: 1 ----------------------
E203 − 16
D4017 Test Method for Water in Paints and Paint Materials by Karl Fischer Method
D4377 Test Method for Water in Crude Oils by Potentiometric Karl Fischer Titration
D4672 Test Method for
...