GB/T 24228-2009Chromium ores and concentrates -- Methods of chemical analysis -- General instruction (English PDF)

3.1 Reagents

3.1.1 All reagents used shall be of recognized analytical grade reagents.

3.1.2 Reagent preparation and analysis of the entire process should use distilled or deionized water, determination of trace elements should be used during the second steam Distilled or deionized water.

3.1.3 flask was diluted to the mark, the temperature should be at 20 °C.

3.1.4 Unless otherwise specified, the temperature of hot water or hot solution refers to the 70 °C ~ 80 °C; the temperature of warm water or warm solution refers to the 40 °C ~ 60 °C.

3.1.5 by the concentration of the liquid reagent prepared in a non-standard solution (Vp Vp 1 + 2), is about a specific volume of solution added to 1 volume Vp Solvent Vp 2.

3.1.6 concentration was expressed as follows.

a) the mass fraction. mass (g) per 100g solution components as a percentage (%) indicates;

b) concentration. mass per liter of solution components (g), in grams per liter (g/L);

c) the volume fraction. volume of solution per 100mL component (mL), percentage (%) represented;

d) the concentrations of the components. the amount of substance per liter of solution components, expressed in moles per liter (mol/L).

3.1.7 Calibration standard solution should be at least three replicates.

3.2 Instrument

3.2.1 Weighing Analytical Balances used precision level not less than three, the sense should reach 0.1mg. Balance and weight regularly by qualified Quality measurement test of the department.

3.2.2 Volumetric Apparatus (flask, burette, pipette, etc.) should be used in the national standard A-class products, according to relevant national regulations for calibration.

3.2.3 Select measuring the absorbance of the cuvette, to meet the measurement requirements.

3.3 Sample

Chemical analysis shall be air-dried or sample at 105 °C ~ 110 °C dried sample.

3.4 Analysis Steps

3.4.1 Analysis of sample number

Determination of chromium and chromium ore concentrate specific elements should be analyzed simultaneously sample two or three samples.

Should repeat the sample analysis results obtained arithmetic mean value as the final result. The poor results obtained shall not exceed the relevant standard clauses