ISO 10203:2015 pdf download

ISO 10203:2015 pdf download.Iron ores — Determination of calcium — Flame atomic absorption spectrometric method
1 Scope
This International Standard specifies a flame atomic absorption spectrometric method for the determination of the mass fraction of calcium in iron ores.
This method is applicable to mass fractions of calcium between 0,010 % and 8,00 % in natural iron ores,iron ore concentrates, and agglomerates, including sinter products.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 648, Laboratory glassware — Single-volume pipettes
ISO 1042, Laboratory glassware — One-mark volumetric flasks
ISO 3082, Iron ores — Sampling and sample preparation procedures
ISO 3696, Water for analytical laboratory use — Specification and test methods
ISO 7764, Iron ores — Preparation of predried test samples for chemical analysis
ISO 80000-1:2009, Quantities and units — Part 1: General
ISO Guide 35, Reference materials — General and statistical principles for certification
3 Principle
The test portion is decomposed by the treatment with hydrochloric acid and a small amount of nitric acid, and then evaporated to dehydrate silica, followed by dilution and filtration.
The residue is ignited and silica is removed by evaporation with hydrofluoric and sulfuric acids. The residue is fused with sodium carbonate and the cooled melt is dissolved in the filtrate.
The solution obtained is aspirated into the flame of an atomic absorption spectrometer using a dinitrogen oxide/acetylene burner.
The absorbance values obtained for calcium are compared with those obtained from calibration solutions.
4 Reagents
During the analysis, use only reagents of recognized analytical grade and only water that complies with Grade 2 of ISO 3696.
4.8 Background solution.
Dissolve 5,0 g pure iron (4.7) in 50 ml of hydrochloric acid (4.2) and oxidize by adding nitric acid (4.4) drop by drop. Evaporate until a syrupy consistency is obtained. Add 20 ml of hydrochloric acid (4.2) and dilute to 200 ml with water. Dissolve 17 g of sodium carbonate (4.1) in water, add carefully to the iron solution, and heat to remove carbon dioxide. Transfer the cooled solution to a 1 000 ml one-mark volumetric flask, dilute to volume with water, and mix.
4.9 Lanthanum chloride solution.
Dissolve 50 g of lanthanum chloride (LaCl 3 ·7H 2 O) (of mass fraction of calcium less than 0,002 %) in 50 ml of hydrochloric acid (4.2) and 300 ml of hot water. Cool and dilute to 1 l.
4.10 Calcium standard solution, 25 μg Ca/ml.
Dissolve 1,248 7 g of dried calcium carbonate (CaCO 3 ) [minimum purity 99,9 % (mass fraction), dried at 105 °C for 1 h] in 100 ml of hydrochloric acid (4.2), diluted 1 + 3. When dissolved, cool, transfer to a 1 000 ml one-mark volumetric flask, dilute to volume with water, and mix. Transfer 10 ml of this solution to a 200 ml one-mark volumetric flask, dilute to volume with water, and mix.