|
Ref. No. : ISO/R 925-1969 (E)
IS0
O R G A N IZAT I O N FOR STAN DA RD IZATl O N
I NT ERN AT1 ON A L
IS0 RECOMMENDATION
L
R 925
DETERMINATION OF CARBON DIOXIDE IN COAL
BY THE GRAVIMETRIC METHOD
1st EDITION
January 1969
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.
---------------------- Page: 1 ----------------------
BRIEF HISTORY
IS0 Recommendation R 925, Determination of carbon dioxide in coal by the gravimetric
The
method, was drawn up by Technical Committee ISOlTC 27, Solid mineral fuels, the Secretariat of
which is held by the British Standards Institution (BSI).
Work on this question by the Technical Committee led, in 1966, to the adoption of a Draft
IS0 Recommendation.
In November 1966, this Draft IS0 Recommendation (No. 1125) 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 India Spain
Austria Ireland South Africa, Rep. of
Belgium Italy Sweden
Bulgaria Switzerland
Japan
Canada Korea, Rep. of
Turkey
Chile Netherlands U.A.R.
Czechoslovakia New Zealand United Kingdom
Denmark Poland U.S.S.R.
France
Portugal Yugoslavia
Germany Romania
No Member Body opposed the approval of the Draft.
The Draft IS0 Recommendation was then submitted by correspondence to the IS0 Councii,
which decided, in January 1969, to accept it as an IS0 RECOMMENDATION.
-2-
---------------------- Page: 2 ----------------------
ISO/R 925-1969 (E
R 925
IS0 Recommendation January 1969
DETERMINATION OF CARBON DIOXIDE IN COAL
BY THE GRAVIMETRIC METHOD
1. SCOPE
This IS0 Recommendation describes the gravimetric method for the determination of carbon dioxide
in the mineral carbonates associated with hard coal.
NOTE. - The result obtained will include any carbon dioxide absorbed by the coal.
2. PRINCIPLE OF THE METHOD
The sample of coal is treated with hydrochloric acid which reacts with the carbonates present to
liberate carbon dioxide. The carbon dioxide resulting from the decomposition of the carbonate is
absorbed and weighed.
3. REAGENTS
All reagents, unless otherwise specified, should be of analytical reagent quality, and water free from
carbon dioxide should be used throughout (see Note 1 below).
3.1 Hydrochloric acid, approximately 3 N.
3.2 Copper phosphate, granular, particle size 0.7 to 1.2 mm.
3.3 Magnesium perchlorate, dried, particle size 0.7 to 1.2 mm (see Note 2 below).
3.4 Soda-asbestos, particle size 1.2 to 1.7 mm, preferably self-indicating.
NOTES
1. Distilled water may be freed from carbon dioxide by boiling gently for 15 minutes.
2. Regeneration of magnesium perchlorate should not be attempted, owing to the risk of explosion. When
exhausted, the magnesium perchlorate should be washed down the sink with a stream of water.
-3-
---------------------- Page: 3 ----------------------
ISO/R 925 -1969 (
I
4. APPARATUS
All graduated apparatus should be of the best analytical quality available.
The system comprises a purification train, a reaction flask assembly and an absorption train. A suit-
able apparatus is shown in the Figure, and consists of :
Purification train. A bubbler containing sulphuric acid (d = 1.84) and an absorption tube
4.1
containing soda-asbestos.
Reaction flask assembly. A 300 ml flat-bottomed flask fitted with a tap funnel, a double-
4.2
surface condenser and a bulbed tube.
4.3 Absorption îrain. Three absorption tubes packed respec
...