ASTM E2403-04

Standard Test Method for Sulfated Ash of Organic Materials by Thermogravimetry

SCOPE
1.1 This standard describes the determination of sulfated ash content (sometimes called residue-on-ignition) of organic materials by thermogravimetry. The method converts common metals found in organic materials (such as sodium, potassium, lithium, calcium, magnesium, zinc, and tin0 into their sulfate salts permitting estimation of their total content as sulfates or oxides. The range of the test method is from 0.1 to 100 % metal content.
1.2 SI values are the standards.
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 to determine the applicability of regulatory limitations prior to use.

General Information

• Status: Historical
• Publication Date: 30-Sep-2004
• ICS: 71.040.40 - Chemical analysis
• Technical Committee: E37 - Thermal Measurements
• Drafting Committee: E37.01 - Calorimetry and Mass Loss

Relations

• Replaced By: ASTM E2403-06 - Standard Test Method for Sulfated Ash of Organic Materials by Thermogravimetry
• Effective Date: 01-Mar-2006

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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.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:E2403–04
Standard Test Method for
Sulfated Ash of Organic Materials by Thermogravimetry
This standard is issued under the fixed designation E 2403; 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 (e) indicates an editorial change since the last revision or reapproval.
1. Scope The United States Pharmacopeia XXII and The National
Formulary XVII, United States Pharmacopeial Conven-
1.1 This standard describes the determination of sulfated
tion, Rockville, MD, 1990, Section 281, p.1527.
ash content (sometimes called residue-on-ignition) of organic
materials by thermogravimetry. The method converts common
3. Terminology
metals found in organic materials (such as sodium, potassium,
3.1 Definitions: Technical terms used in this standard are
lithium, calcium, magnesium, zinc, and tin0 into their sulfate
defined in Terminologies E 473 and E 1142
salts permitting estimation of their total content as sulfates or
3.1.1 sulfated ash, n—the residue remaining after a speci-
oxides.Therangeofthetestmethodisfrom0.1to100 %metal
men has been oxidized, and the residue subsequently treated
content.
with sulfuric acid and heated to constant weight.
1.2 SI values are the standards.
3.1.2 residue-on-ignition, ROI, n—a commonly used alias
1.3 This standard does not purport to address all of the
for sulfated ash.
safety concerns, if any, associated with its use. It is the
3.1.3 volatiles, n—for the purpose of this test, those mate-
responsibility of the user of this standard to establish appro-
rials evolving as gas at temperatures below 160 °C in an air
priate safety and health practices and to determine the
atmosphere.
applicability of regulatory limitations prior to use.
4. Summary of Test Method
2. Referenced Documents
2 4.1 A test specimen is ignited and burned in an air atmo-
2.1 ASTM Standards:
sphere at temperatures up to 600 °C until only ash remains.
D 874 Test Method for Sulfated Ash from Lubricating Oils
After cooling, the residue is treated with sulfuric acid and
and Additives
heated to 800 °C to constant weight. The residue remaining is
D 914 Test Method for Ethylcellulose
identified as sulfated ash.
D 3516 Test Methods for Ashing Cellulose
4.2 This test method is similar to D 874 for lubricating oils
E 473 Terminology Relating to Thermal Analysis
and additives, D 914 for ethyl cellulose, D 3516 cellulose, and
E 1131 Standard Test Method for Compositional Analysis
that of the U.S. Pharmacopeia and makes use of thermogravi-
by Thermogravimetry
metric apparatus to perform the determination.
E 1142 Terminology Relating toThermophysical Properties
E 1582 Standard Practice for Calibration of Temperature
5. Significance and Use
Scale for Thermogravimetry
5.1 The sulfated ash may be used to indicate the level of
E 2040 StandardTest Method for Mass Scale Calibration of
known metal-containing additives or impurities in an organic
Thermogravimetric Analyzers
material. When phosphorus is absent, barium, calcium, mag-
2.2 Other Standards
nesium, sodium and potassium are converted to their sulfates.
Tin and zinc are converted to their oxides.
5.2 This standard may be used for research and develop-
ThistestmethodisunderthejurisdictionofASTMCommitteeE37onThermal
ment, specification acceptance and quality assurance purposes.
Measurements and is the direct responsibility of Subcommittee E37.01 on Thermal
and Rheological Test Methods and Practices.
6. Interferences
Current edition approved Oct. 1, 2004. Published November 2004.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
6.1 If phosphorus is present with metals, it partially or
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
wholly remains in the sulfated ash as metal phosphates.
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. 6.2 Sulfur and chlorides do not interfere.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
E2403–04
7. Apparatus 12. Procedure
7.1 Thermogravimetric Analyzer (TGA)—The essential in-
12.1 Transfer 30 to 40 mg of the sample into a tared, clean,
strumentation required to provide the minimum thermogravi-
and dry sample container. Assemble the thermogravimetric
metric analytical capability for this standard includes:
analyzer for operation. Record the initial weight of the test
7.1.1 A thermobalance composed of:
specimen as W to within 6 0.01 mg
o
7.1.1.1 Afurnace to provide uniform controlled heating of a
NOTE 1—The sample container may be preconditioned by heating in an
specimen to a constant temperature of 850 °C and at a constant
air atmosphere to 800 °C.
rate of 5 to 60 °C/min
NOTE 2—Smaller quantities of test specimen will reduce the quantifi-
7.1.1.2 Atemperature sensor to provide an indication of the
cation capability of this method.
specimen/furnace temperature to 6 1 °C.
7.1.1.3 A continuously recording balance to measure the 12.2 Heat the specimen from ambient to 600 °C at 10
specimen mass with a minimum capacity of 50 mg and a °C/min under an air purge gas with a flow rate of 50 to 100 6
sensitivity of 6 0.01 mg. 5 mL/min and record the thermal curve.
7.1.1.4 A means of maintaining the specimen/container
12.3 Cool the heated sample and thermogravimetric appa-
under atmospheric control of air at a purge flow rate of 50 to
ratus to 20 to 25 °C.
100 mL/min 6 5 mL/min.
12.4 Ifdesired,recordtheweightat150°C(W )asthemass
v
7.1.2 A temperature controller capable of executing a spe-
after apparent loss of volatiles. Record the weight at 600 °C as
cific temperature program by operating the furnace between
the mass of the residue (W ).
r
selected temperature limit at a rate of 5 to 60 °C/min and to an
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