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STANDARD
9062
Second edition
1992-12-15
Acid-grade and ceramic-grade fluorspar -
Determination of manganese content -
Periodate spectrometric method
Spaths fluor pour Ia fabrication de I’acide fluorh ydrique et spaths fluor
utilisables dans I’industrie ceramique - Dosage du mangankse -
Methode spectrom&rique au Periodate
Reference number
ISO 90623 992(E)
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ISO 9062:1992(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide
federation of national Standards bodies (ISO member bodiesi. The work
of preparing international Standards is normally carried out through ISO
technical committees. Esch member body interested in a subject for
which a technical committee has been established has the right to be
represented on that committee. International organizations, governmental
and non-governmental, in liaison with ISO, also take part in the work. ISO
collaborates closely with the International Electrotechnical Commission
(IEC) on all matters of electrotechnical standardization.
Draft International Standards adopted by the technical committees are
circulated to the member bodies for voting. Publication as an International
Standard requires approval by at least 75 % of the member bodies casting
a vote.
International Standard ISO 9062 was prepared by Technical Committee
lSO/TC 175, Fluorspar.
This second edition cancels and replaces the first edition
(ISO 9062:1989), which has been updated.
0 ISO 1992
Ali rights reserved. No part of this publication may be reproduced or utilized in any form or
by any means, eiectronic or mechanical, including photocopytng and microfilm, without per-
mission in writing from the publisher.
Internattonal Organization for Standardization
Case Postale 56 l CH-l 211 Geneve 20 l Switzerland
Printed in Switzerland
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INTERNATIONAL STANDARD ISO 9062: 1992(E)
Acid-grade and ceramic-grade fluorspar -
Determination of manganese content -
Periodate
spectrometric method
1 Scope 4 Reagents
This International Standard specifies a Periodate During the analysis, use only reagents of recognized
spectrometric method for the determination of the analytical grade, and only distilled water or water of
manganese content of acid-grade and ceramic-grade equivalent purity.
fluorspar.
4.1 Nitrit acid, p approximately 1,40 g/ml, about
The method is applicable to products having
68 % (m/m) Solution.
manganese contents, expressed as Mn, in the range
0,006 % (dm) to 0,4 % (m/m).
4.2 Perchlorit acid, about 70 % (rn/m) Solution.
WARNING - Perchlorit acid vapour may Cause
2 Normative references
explosions in the presence of ammonia, nitrous
fumes or organic matter in general.
The following Standards contain provisions which,
through reference in this text, constitute provisions
of this International Standard. At the time of publi-
4.3 Phosphoric acid, about 85 % (m/m) Solution.
cation, the editions indicated were valid. All Standards
are subject to revision, and Parties to agreements
based on this International Standard are encouraged
4.4 Sodium metaperiodate, 50 g/l Solution.
to investigate the possibility of applying the most re-
cent editions of the Standards indicated below.
Members of IEC and ISO maintain registers of cur- 4.5 Manganese, Standard stock Solution corre-
rently valid International Standards. sponding to 1 000 mg of Mn per litre.
Dissolve 0,5 g of pure metallic manganese
ISO 565: 1990, Test sieves - Metal wire cloth, per-
( > 99,5 % purity) in 20 ml of water and 20 ml of nitric
forated metal plate and electroformed sheet - Nom-
acid (4.1). Add 50 ml of water and boil for 10 min.
inal sizes of openings.
Leave to cool. Transfer the Solution quantitatively to
a 500 ml volumetric flask, dilute to the mark with
ISO 8868: 1989, Fluorspar - Sampling and Sample
water and mix.
prepara tion.
1 ml of this Standard stock Solution contains
1 000 pg of Mn.
3 Principle
4.6 Manganese, Standard Solution A corresponding
Decomposition of the test Portion in a platinum dish
to 100 mg of Mn per Iitre.
using nitric and perchloric acids. After dilution,
Oxidation of the manganese in an aliquot Portion of
into a 250 ml volumetric flask, introduce 25,0 ml of
the Solution to permanganate ion using sodium
the manganese Standard stock Solution (4.5), dilute to
metaperiodate, and spectrometric measurement of
the mark with water and mix.
the absorbance maximum at a wavelength of
1 ml of this Standard Solution contains 100 pg of Mn.
545 nm.
1
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ISO 9062:1992(E)
4.7 Manganese, Standard Solution B corresponding weigh, to the nearest 0,2 mg, about 1,0 g of this
to 20 mg of Mn per litre. Sample into the platinum dish (5.2).
Into a 250 ml volumetric flask, introduce 50,O ml of Add 2 ml to 3 ml of water and agitate slightly to sus-
the manganese Standard Solution A (4.6), dilute to the pend the Sample in the water. Add 10 ml of nitric acid
mark with water and mix. (4.1) and 10 ml of perchloric acid (4.2). Heat carefully
until fumes of perchlnric acid are evolved and maintain
1 ml of this Standard Solution contains 20 pg of Mn.
gentle fume development for 5 min. Allow to cool and
add 2 ml to 3 ml of water. Heat again until fumes of
perchloric acid are again evolved and again maintain
5 Apparatus
gentle fume development for 5 min. Allow to cool.
Add 10 ml of water and 5 ml of nitric acid and warm
Ordinary laboratory apparatus, and
to dissolve the salts. Transfer the Solution
quantitatively to a 150 ml beaker. Place a glass cover
5.1 Electric oven, capable of being maintained at a
on the beaker and heat until fumes of perchloric acid
temperature of 105 “C + 2 “C.
-
are evolved and the perchloric acid refluxes down the
sides of the beaker. Allow to reflux for 5 min. DO not
allow the volume of perchloric acid to decrease to less
5.2 Platinum dish, of approximately 100 ml ca-
than 3 ml. Add further perchloric acid if necessary.
pacity.
Allow to cool.
Add 20 ml of water and 5 ml of nitric acid. Heat to
5.3 Platinum crucible, of 30 ml capacity.
boiling and boil gently for 5 min. Allow to cool. Trans-
fer quantitatively to a 100 ml volumetric flask, dilute
5.4 Spectrometer, with a radiation selector for
with water to the mark and mix.
continuous Variation, capable of measuring
If there is an appreciable amount of insoluble material,
absorbance to within 0,001 absorbance units at a
treat the Solution as follows.
wavelength of 545 nm, or
Quantitatively transfer the Solution and insoluble ma-
5.5 Spectrometer, with a radiation selector for dis-
terial on to a small close-textured filter Paper, collect-
continuous Variation, fitted with filters giving a maxi-
ing the filtrate in a 100 ml volumetric flask. Wash the
mum transmission and capable of measuring
filter Paper three times with hot water. Transfer the
absorbance to within 0,001 absorbance units at a
filter Paper and contents to the platinum crucible
wavelength of 545 nm. (5.3), dry and then incinerate at 500 “C to 600 “C.
Fuse the
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