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IS0
O R G A N I ZATl ON FO R STA N DAR DI ZATl ON
I N T ERN AT1 O N A L
IS0 RECOMMENDATION
R 803
ALUMINIUM OXIDE PRIMARILY USED
FOR THE PRODUCTION OF ALUMINIUM
DETERMINATION OF LOSS OF MASS AT 300 "C
(CON V E NT I O NA L MO I STU R E)
1st EDITION
August 1968
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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
in French and Russian. Copies to be obtained through the national standards organizations.
Also issued
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BRIEF HISTORY
The IS0 Recommendation R 803, Aluminium oxide primarily used for the production of
aluminium - Determination of loss of mass at 300 "C (Conventional moisture), was drawn up by
Technical Committee ISO/TC 47, Chemistry, the Secretariat of which is held by the Ente Nazionale
Italian0 di Unificazione (UNI).
_-
Work on this question by the Technical Committee began in 1961 and led, in 1964, to the
_-
adoption of a Draft IS0 Recommendation.
In July 1966, this Draft IS0 Recommendation (No. 1025) 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 :
India South Africa, Rep. of
Austria
Ireland
Belgium Spain
Brazil Israel Sweden
Bulgaria Italy Switzerland
Canada Japan Turkey
U.A.R.
Chile Korea, Rep. of
Czechoslovakia Netherlands United Kingdom
France Norway U.S.A.
Germany Poland U.S.S.R.
Romania Yugoslavia
Hungary
No Member Body opposed the approval of the Draft.
The Draft IS0 Recommendation was then submitted by correspondence to the IS0 Council,
which decided, in August 1968, to accept it as an IS0 RECOMMENDATION.
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ISOlR 803-1968 IE
R 803 August 1968
IS0 Recommendation
ALUMINIUM OXIDE PRIMARILY USED
FOR THE PRODUCTION OF ALUMINIUM
DETERMINATION OF LOSS OF MASS AT 300 "C
(CON V E NT I O NA L MO I STU R E)
INTRODUCTION
Depending on its degree of calcination, aluminium oxide shows a tendency to readsorb variable
quantities of water by a process involving physical forces (residual activity).
The water readsorbed cannot be completely eliminated by simply drying at 105 OC, the temperature
usually employed for the determination of moisture. Therefore, it is necessary to use a suitably
higher drying temperature. It is accepted that elimination of water is almost complete at 300 "C and
this temperature is conventionally adopted.
1. SCOPE
This IS0 Recommendation describes the method for the determination of loss of mass on drying at
300 "C (conventional moisture).
2. PFUNCiPLE
Drying at 300 "C for 2 hours and determination of loss of mass.
3. APPARATUS
Ordinary laboratory apparatus and
Desiccator, preferably containing freshly activated alumina or phosphorus pentoxide (the use of
3.1
calcium chloride should be avoided).
3.2 Weighing bottle, squat form, approximately 45 mm in diameter.
3.3 Electric oven, ventilated by convection and controlled at 300 f 10 OC.
4. PROCEDURE
4.1 Test portion
Weigh to the nearest 0.001 g, approximately 5 g of the crude sample* in the weighing bottle
(3.2), previously dried at 300 "C and tared.
* See IS0 Recommendation R 802, Aluminium oxide pnmarly used for the production of aluminium
- Preparation and storage of test samples, clause 2.2.
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ISOlR 803-1968 (E
4.2 Determination
Place the uncovered weighing bottle and its lid in the oven (3.3) and heat for 2 hours. Remove
weighing bottle and lid from the oven and place in the desiccator (3.1) without covering the
weighing bottle completely. After 30 minutes cooling, cover the weighing bottle and weigh it.
5. EXPRESSION OF RESULTS
The loss of mass at 300 "C is expressed as a percentage (m/m) by the following formula :
m2 -ml x 100
E
where
is the mass, in grammes, of the weighing bottle containing the test portion before
m2
drying,
is the mass, in grammes, of the weighing bottle containing the test portion after drying,
ml
E is the mass, in grammes, of the test portion.
6. TEST REPORT
Give the following particulars :
the reference to the method used,
(U)
the results and the method of expression used,
(b)
any unusual features noted during the determination,
(c)
any operation not included in this IS0 Recommendation or regarded as optional.
(d)
I
I
I
Date of the first printing : Price : Sw. fr. 4.51
November 1968
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ISO/R 804 -1968 (E)
IS0 Recommendation R 804 August 1968
ALUMINIUM OXIDE PRIMARILY USED
FOR THE PRODUCTION OF ALUMINIUM
PREPARATION OF SAMPLE SOLUTION FOR ANALYSIS
1. SCOPE
This IS0 Recommendation describes the method of preparation of a sample solution in order to
obtain a principal solution (solution P) for certain chemical tests.
2. PRINCIPLE
Alkaline fusion of aluminium oxide
-
either with a mixture of sodium carbonate and boric acid,
-
or with a mixture of sodium carbonate and sodium tetraborate.
Dissolution of the melt in an excess of nitric acid (see clause 6.1) so that the pH of the final solution
is approximately 1, after dilution to 500 ml, or approximately 0.4, after dilution to 250 ml.
3. REAGENTS
Distilled water or water of equivalent purity should be used in the test.
3.1 Sodium carbonate, anhydrous.
3.2 Boric acid (H,BO,).
3.3 Sodium tetraborate, anhydrous (Na, B,O,).
3.4 Aluminium oxide, pure.
3.5 approximately 8 N solution. Dilute 540 ml of approximately d = 1.4 nitric acid
Nitric a
...