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Ref. No.: ISO/R 562 - 1967 (E)
I N T ERN AT1 ON A L O RG A N I Z AT I O N FOR STA N DA RD lZ AT1 O N
IS0 RECOMMENDATION
R 562
DETERMINATION OF THE VOLATILE MATTER
OF HARD COAL AND OF COKE
1st EDITION
March 1967
COPYRIGHT RESERVED
The copyright of IS0 Recommendations and IS0 Standards
belongs to IS0 Member Bodies. Reproduction of these
documents, in any country, may be authorized therefore only
by the national standards organization of that country, being
a member of ISO.
For each individual country the only valid standard is the national standard of that country.
Printed in Switzerland
Also issued in French and Russian. Copies to be obtained through the national standards organizations.
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BRIEF HISTORY
The IS0 Recommendation R 562, Determination of the Volatile Matter of Hard Coal and
of Coke, was drawn up by Technical Committee ISO/TC 27, Solid Mineral Fuels, the Secretariat
of which is held by the British Standards Institution (BSI).
Work on this question by the Technical Committee began in 1950 and led, in 1961, to the
adoption of a Draft IS0 Recommendation.
In October 1962, this Draft IS0 Recommendation (No. 550) was circulated to all the IS0
Member Bodies for enquiry. It was approved, subject to a few modifications of an editorial
nature, by the following Member Bodies :
Australia Iran Sweden
Austria Italy Switzerland
Belgium
Japan Turkey
Brazil Poland United Kingdom
Chile Portugal U.S.A.
Czechoslovakia Republic U.S.S.R.
Germany of South Africa Yougoslavia
Greece Romania
India Spain
Two Member Bodies opposed the approval of the Draft:
France,
Netherlands
The Draft IS0 Recommendation was then submitted by correspondence to the IS0
Council, which decided, in March 1967, to accept it as an IS0 RECOMMENDATION.
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I
ISO/R 562 - 1967 (E)
IS0 Recommendation R 562 March 1967
DETERMINATION OF THE VOLATILE MATTER
OF HARD COAL AND OF COKE
INTRODUCTION
The volatile matter content is determined as the loss in mass, less that due to moisture, when
coal or coke is heated out of contact with air under standardized conditions. The test is empirical
and, in order to ensure reproducible results, it is essential that the rate of heating, the final tem-
perature and the overall duration of the test should be carefully controlled. The moisture content
of the sample should be determined at the same time as the volatile matter so that the appro-
priate'correction can be made.
Mineral matter associated with the sample may also lose mass under the conditions of test, the
magnitude of the loss being dependent on both the nature and the quantity of the minerals present.
When the carbonate content of a coal is high or when the result is required for the purpose of
classifying the coal, it is necessary to make a correction to the determined volatile matter for the
loss of carbon dioxide occurring during the determination. A first approximation to this cor-
rection is obtained by the use of the third formula in section 6.
NOTE. - Insufficient experimental evidence is available to justify a correction for loss of carbon dioxide being
recommended when determining the volatile matter of coke. On the other hand, the error from this source is
unlikely to be great, as carbonates are decomposed in the coke oven in making coke, although some carbonates
may be added subsequently if the coke is quenched with waste liquor.
The apparatus and procedure are so specified that one or more determinations may be carried
out simultaneously in the muffle furnace.
1. SCOPE
This IS0 Recommendation describes the method of determining the volatile matter of hard coal
and of coke. It is not applicable to brown coals and lignites.
2. PRINCIPLE
The coal or coke is heated at 900 "C out of contact with air for 7 minutes. The percentage of
volatile matter is calculated from the loss in mass of the sample after deducting the loss in mass
due to moisture.
3. REAGENTS
3.1 Desiccant. Fresh or freshly regenerated and self indicating. Suitable desiccants are silica
gel, activated alumina and anhydrous calcium sulphate.
3.2 Benzene (for use with coke samples).
4. APPARATUS
4.1 Muffle furnace, heated by gas or electricity in which an adequate zone of constant and uniform
temperature of 900 + 10 "C can be maintained. It may be of the stop-ended type or fitted
at the back with a flue approximately 25 mm diameter by 150 mm long.
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ISO/R 562 - 1967 (E)
Its heat capacity is such that, with an initiai temperature of 900 OC, a minimum temperature
of 885 "C is regained within 4 minutes, preferably within 3 minutes, of the insertion of a
cold stand and its crucible(s), the temperature being measured with an unsheathed thermo-
couple, as described below. Normally the furnace * will be designed specifically either for
receiving one crucible and its stand or for multiple determinations using a number of
crucibles in one stand.
NOTE. - The temperature of 900 "C should be attained as closely as possible and the tolerance of & 10°C
is specified so as to meet inherent errors in the temperature measurement and lack of uniformity in the tem-
perature distribution.
A position for the crucible stand is chosen within the zone of uniform temperature and this
position is used for all determinations.
4.2 Pyrometer. The temperature characteristics of the furnace are checked with an unsheathed
thermocouple, of wire not thicker than I mm. The thermojunction is inserted midway
between the base of the crucible in its stand and the floor of the furnace. If the stand holds
more than one crucible, then the temperature under each crucible is checked in the same
manner. If desired, a sheathed thermocouple may be permanently installed in the furnace
with its thermojunction as close as possible to the centre of the zone of uniform temperature;
in this case, its temperature readings should be correlated at frequent intervals with those
of the unsheathed thermocouple, which is then inserted only when necessary.
NOTE. - The temperature/electromotive force relationship of a thermojunction maintained at elevated
temperatures gradually changes with time.
4.3 Crucible and lid. A cylindrical crucible with a well fitting lid, both of fused silica. The
silica crucible and lid should weigh between 10 and 14 g and have dimensions approxi-
mating to those shown in Figure 1. The fit of the lid on the crucible is critical to the deter-
mination and a lid should be selected to match the crucible so that the horizontal clearance
between them is not greater than 0.5 mm. After selection, the crucible and the lid should
be ground together to give smooth surfaces and then be given a common distinguis
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