AS ISO 19976.1:2020 pdf free download – Copper, lead and zinc sulfide concentrates —Determination of cadmium Part 1: Flame atomic absorption spectrometric method

AS ISO 19976.1:2020 pdf free download – Copper, lead and zinc sulfide concentrates —Determination of cadmium Part 1: Flame atomic absorption spectrometric method.
These standards contain 0,0 pg. 0,2 11g. 0,4 pg. 0,611g. 0,7 pg. 0,8 1’X. 0,9 pg and 1,0 pg of cadmium per ml and shall be freshly prepared.
Calibration solutions should be prepared at the same ambient temperature as that at which the determinations will be conducted
6 Apparatus
Ordinary laboratory equipment and the following.
6.1 Volumetric glassware. ol class A conforming with ISO 385. ISO 648 and ISO 1042, and used in accordance with ISO 4787.
It is permissible to use other measuring instruments, approved types, auxiliary devices and materials whose technical and metrological characteristics are not interior to those mentioned above,
6.2 Polytetrafluoroethylene beaker, of capacIty 200 ml. or glass-carbon beaker.
6.3 AnalytIcal balance, sensitive to 0,1 mg.
6.4 AAS. equipped with a cadmium hollow cathode lamp and deutenum lamp for background correction.
Recommended Instrument conditions:
— flame: air-acetylene;
— wavelength: 228,8 nm;
— slit width: 0.2 nm.
6.5 Insolubles filter paper, WhatmanJ No.40 or equivalent.
7 Samples
7.1 L.aboratoty sample
Laboratory samples shall be taken and prepared In accordance with the procedures described in ISO 12743.
7.2 Test sample
Prepare an air-equilibrated test sample in accordance with ISO 9599.
NOTE A test sample k not required If prcdricd test portions are to be used (see Annex A).
7.3 Test portion
Taking multiple increments, extract approximately 0,50 g from the test sample and weigh to the nearest 0,1 mg. At the same time as test portions are being weighed for analysis, weigh test portions for the determination of hygroscopic moisture in accordance with ISO 9599.
Alternatively, the method specified In Annex A can be used to prepare pre-dried test portions directly from the laboratory sample
This annex specifies a method for the preparation and determination of the mass of a predried test portion In the analysis of copper, lead and zinc sulfide concentrates.
The method is applicable to copper, lead and zinc sulfide concentrates not susceptible to oxidation and with hygroscopic moisture contents ranging from 0,05 % to 2 %.
A.2 Principle
The test portion to be used for analysis is dried in air in an oven maintained at 105 °C ± 5 °C. The dried test portion is then weighed and used for the analysis. No correction for hygroscopic moisture is required.
A.3 Chemicals
A.3.1 Desiccant, such as self-indicating silica gel or anhydrous magnesium perchlorate.
WARNING — Care must be taken when disposing of exhausted magnesium perchlorate. It must be washed down the sink with a stream of running water.
A.4 Apparatus
Ordinary laboratory equipment, and the following.
A.4.1 Analytical balance, sensitive to 0,1 mg.
A.4.2 Weighing vessels, of glass or silica or corrosion-resistant metal, with externally fitting airtight covers. For small test portions (of mass less than 3 g). the mass of the vessel shall be as small as possible, i.e. less than 20 g.
A.4.3 Laboratory oven, capable of maintaining a temperature of 105°C ± 5 °C.
A.5 Procedure
A.5.1 Preparation of the weighing vessel
Dry the weighing vessel and its cover (A.4.2) by heating in the laboratory oven (A.4.3) at 105 °C ± 5 °C for 1 h. Transfer the vessel and its cover to a desiccator containing a suitable fresh desiccant (A3..1) and allow to cool to ambient temperature.
Tare the dried weighing vessel and its cover (A.5.1). Immediately add the mass of laboratory sample specified for analysis. An accurate total mass of the test portion and weighing vessel is not required at this point.
A.5.3 Determination of the test portion dry mass
Transfer the uncovered weighing vessel and the test portion and the vessel cover to the laboratory oven (A.4.3) and dry at 105 °C ± 5 °C for 2 h. After the 2 h period, remove the weighing vessel and dry test portion from the oven, replace the vessel cover and allow to cool to ambient temperature in the desiccator. When cool, remove the weighing vessel containing the dry test portion and the vessel cover from the desiccator, and weigh to the nearest 0,1 rug (ml) after slightly lifting the cover and quickly replacing it.
Transfer the test portion into the appropriate analytical apparatus and immediately reweigh the empty weighing vessel and its cover. Record the mass (m2) to the nearest 0,1 mg.