GB/T 14353.21-2019Methods for chemical analysis of copper ores, lead ores and zinc ores—Part 21: Determination of arsenic content—Hydride generation atomic fluorescence spectrometry (English PDF)

Foreword

GB/T 14353 "Chemical Analysis Methods for Copper Ore, Lead Ore and Zinc Ore" is divided into 21 parts.

--- Part 1. Determination of copper content;

--- Part 2. Determination of lead content;

--- Part 3. Determination of zinc content;

--- Part 4. Determination of cadmium content;

---Part 5. Determination of nickel content;

---Part 6. Determination of cobalt content;

---Part 7. Determination of arsenic content;

--- Part 8. Determination of volume;

---Part 9. Determination of molybdenum content;

--- Part 10. Determination of tungsten content;

--- Part 11. Determination of silver content;

--- Part 12. Determination of sulfur content;

--- Part 13. Determination of the amount of gallium, indium, niobium, tungsten and molybdenum;

--- Part 14. Determination of enthalpy;

---Part 15. Determination of selenium content;

---Part 16. Determination of enthalpy;

--- Part 17. Determination of enthalpy;

---Part 18. Determination of copper, lead, zinc, cobalt and nickel;

---Part 19. Determination of tin content by hydride generation atomic fluorescence spectrometry;

--- Part 20. Determination of enthalpy inductively coupled plasma mass spectrometry;

--- Part 21. Determination of arsenic content by hydride generation atomic fluorescence spectrometry.

This part is the 21st part of GB/T 14353.

This part is drafted in accordance with the rules given in GB/T 1.1-2009.

1 Scope

This part of GB/T 14353 specifies arsenic atomic fluorescence spectrometry for the determination of arsenic in copper ore, lead ore and zinc ore content.

This section applies to the determination of arsenic content in copper ore, lead ore and zinc ore.

Method detection limit: 1.5 µg/g.

Measuring range: 5 µg/g ~ 1500 µg/g.

2 Normative references

The following documents are indispensable for the application of this document. For dated references, only dated versions apply to this document. For undated references, the latest edition (including all amendments) applies to this document.

GB/T 6682 Analytical laboratory water specifications and test methods

GB/T 14505 General rules and general rules for chemical analysis of rocks and ores

3 Principle

The sample is dissolved in nitric acid, potassium chlorate and hydrochloric acid, sulfuric acid is added, and lead is precipitated and separated. In the ammonia solution, iron hydroxide is used as a carrier, and arsenic and Fe(OH)3 coprecipitates and separates copper and zinc. The arsenic-containing precipitate is dissolved in hydrochloric acid, and thiourea-ascorbic acid is added to mask the residual interference in the solution, and reduce pentavalent arsenic to trivalent. In a hydrochloric acid medium, arsenic reacts with potassium borohydride to form arsine, which is loaded into the quartz atomizer by argon. Decomposed into atomic arsenic, high-intensity hollow cathode lamp with arsenic as "excitation" light source, arsenic atom emits fluorescence, and the fluorescence intensity of arsenic is certain The range is proportional to the concentration of arsenic. Determination of the fluorescence intensity of arsenic by atomic fluorescence spectrometry, calculation of samples based on atomic fluorescence intensity The arsenic content in the medium.

4 Reagents or materials

This section uses analytically pure reagents and secondary water in accordance with GB/T 6682, unless otherwise stated.

4.1 Potassium chlorate. analytically pure.

4.2 Hydrochloric acid (rho=1.19g/mL). excellent grade pure.

4.3 Nitric acid (rho=1.42g/mL). excellent grade pure.

4.4 Ammonia water (rho=0.90g/mL).

4.5 Hydrochloric acid solution (1 9).