ASTM E2403-06(2012)

Standard Test Method for Sulfated Ash of Organic Materials by Thermogravimetry

SIGNIFICANCE AND USE
5.1 The sulfated ash may be used to indicate the level of known metal-containing additives or impurities in an organic material. When phosphorus is absent, barium, calcium, magnesium, 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 development, specification acceptance and quality assurance purposes.
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 tin) 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 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this 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 to determine the applicability of regulatory limitations prior to use.

General Information

• Status: Historical
• Publication Date: 31-Aug-2012
• ICS: 71.040.40 - Chemical analysis
• Technical Committee: E37 - Thermal Measurements
• Drafting Committee: E37.01 - Calorimetry and Mass Loss

Relations

• Replaces: ASTM E2403-06 - Standard Test Method for Sulfated Ash of Organic Materials by Thermogravimetry
• Effective Date: 01-Sep-2012

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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.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 − 06 (Reapproved 2012)
Standard Test Method for
Sulfated Ash of Organic Materials by Thermogravimetry
This standard is issued under the fixed designation E2403; 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.
1. Scope 2.2 Other Standards:
The United States Pharmacopeia XXII and The National
1.1 This standard describes the determination of sulfated
Formulary XVII, United States Pharmacopeial
ash content (sometimes called residue-on-ignition) of organic
Convention, Rockville, MD, 1990, Section 281, p. 1527
materials by thermogravimetry. The method converts common
metals found in organic materials (such as sodium, potassium,
3. Terminology
lithium, calcium, magnesium, zinc, and tin) into their sulfate
3.1 Definitions—Technical terms used in this standard are
salts permitting estimation of their total content as sulfates or
oxides. The range of the test method is from 0.1 to 100 % defined in Terminologies E473 and E1142.
3.1.1 sulfated ash, n—the residue remaining after a speci-
metal content.
men has been oxidized, and the residue subsequently treated
1.2 The values stated in SI units are to be regarded as
with sulfuric acid and heated to constant weight.
standard. No other units of measurement are included in this
3.1.2 residue-on-ignition, ROI, n—a commonly used alias
standard.
for sulfated ash.
1.3 This standard does not purport to address all of the
3.1.3 volatiles, n—for the purpose of this test, those mate-
safety concerns, if any, associated with its use. It is the
rials evolving as gas at temperatures below 160°C in an air
responsibility of the user of this standard to establish appro-
atmosphere.
priate safety and health practices and to determine the
applicability of regulatory limitations prior to use.
4. Summary of Test Method
2. Referenced Documents
4.1 A test specimen is ignited and burned in an air atmo-
sphere at temperatures up to 600°C until only ash remains.
2.1 ASTM Standards:
After cooling, the residue is treated with sulfuric acid and
D874 Test Method for Sulfated Ash from Lubricating Oils
heated to 800°C to constant weight. The residue remaining is
and Additives
identified as sulfated ash.
D914 Test Methods for Ethylcellulose
D3516 Test Methods for Ashing Cellulose
4.2 This test method is similar to Test Method D874 for
E473 Terminology Relating to Thermal Analysis and Rhe-
lubricating oils and additives, Test Methods D914 for ethyl
ology
cellulose, Test Methods D3516 cellulose, and that of The
E1131 Test Method for CompositionalAnalysis by Thermo-
United States Pharmacopeia XXII and makes use of thermo-
gravimetry
gravimetric apparatus to perform the determination.
E1142 Terminology Relating to Thermophysical Properties
E1582 Practice for Calibration of Temperature Scale for
5. Significance and Use
Thermogravimetry
5.1 The sulfated ash may be used to indicate the level of
E2040 Test Method for Mass Scale Calibration of Thermo-
known metal-containing additives or impurities in an organic
gravimetric Analyzers
material. When phosphorus is absent, barium, calcium,
magnesium, sodium and potassium are converted to their
sulfates. Tin and zinc are converted to their oxides.
ThistestmethodisunderthejurisdictionofASTMCommitteeE37onThermal
Measurements and is the direct responsibility of Subcommittee E37.01 on Calo- 5.2 This standard may be used for research and
rimetry and Mass Loss.
development, specification acceptance and quality assurance
Current edition approved Sept. 1, 2012. Published September 2012. Originally
purposes.
approved in 2004. Last previous edition approved in 2006 as E2403 – 06. DOI:
10.1520/E2403-06R12.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or 6. Interferences
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
6.1 If phosphorus is present with metals, it partially or
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. wholly remains in the sulfated ash as metal phosphates.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
E2403 − 06 (2012)
6.2 Sulfur and chlorides do not interfere. 11. Calibration and Standardization
11.1 Perform temperature calibration of the thermogravi-
7. Apparatus
metric analyzer according to Practice E1582 using reference
materials suitable for the temperature range of this method,
7.1 Thermogravimetric Analyzer (TGA)—The essential in-
namely 25 to 800°C.
strumentation required to provide the minimum thermogravi-
metric analytical capability for this standard includes:
11.2 Perform mass calibration of the thermogravimetric
analyzer according to Test Method E2040.
7.1.1 A thermobalance composed of:
7.1.1.1 Afurnace to provide uniform controlled heating of a
12. Procedure
specimen to a constant temperature of 850°C and at a constant
12.1 Transfer 30 to 40 mg of the sample into a tared, clean,
rate of 5 to 60°C/min
and dry sample container. Assemble the thermogravimetric
7.1.1.2 Atemperature sensor to provide an indication of the
analyzer for operation. Record the initial weight of the test
specimen or furnace temperature to 61°C.
specimen as W to within 60.01 mg
o
7.1.1.3 A continuously recording balance to measure the
NOTE 1—The sample container may be preconditioned by heating in an
specimen mass with a minimum capacity of 50 mg and a
air atmosphere to 800°C.
sensitivity of 60.01 mg.
NOTE 2—Smaller quantities of test specimen will reduce the quantifi-
7.1.1.4 A means of maintaining the specimen or container
cation capability of this method.
under atmospheric control of air at a purge flow rate of 50 to
12.2 Heat the specimen from ambient to 600°C at 10°C/min
100 mL/min 6 5 mL/min.
under an air purge gas with a flow rate of 50 to 100 6 5
7.1.2 A temperature controller capable of executing a spe-
mL/min and record the thermal curve.
cific temperature program by operating the furnace between
12.3 Cool the heated sample and thermogravimetric appa-
selected temperature limit at a rate of 5 to 60°C/min and to an
ratus to 20 to 25°C.
isothermal temperature of up to 850°C which is maintained
12.4 If desired, record the weight at 150°C (W ) as the mass
constant to 610°C for a minimum of 70 minutes.
v
after apparent loss of volatiles. Record the weight at 600°C as
7.1.3 Arecording device, capable of recording and display-
the mass of the residue (W ).
ing any fraction of the specimen mass signal (TGA curve) r
including signal noise.
NOTE 3—Mass loss due to apparent loss of volatiles at 150°C and
residue at 600°C are not required for the sulfated ash determination but
7.1.4 Containers (pans, crucibles, etc.) that are inert to the
may be recorded for additional sample characterization (see Test Method
specimenandtoconcentratedsulfuricacidandthatwillremain
E1131.)
gravimetrically stab
...