SN/T 5252-2020Determination of Cu, Cr, Mn, Ba, Co, TI.Nb, Ta, Ti, Mo, Y, La, Ce, Pr, Nd, Sm, EU, Gd, Dy, Ho, Er, Tm, Yb in imported iron ore-Inductively coupled plasma mass spectrometry(ICP-MS) (English PDF)

Foreword

This standard was drafted in accordance with the rules given in GB/T 1.1-2009.

This standard was proposed and managed by the General Administration of Customs of the People's Republic of China.

Drafting organizations of this standard. Qingdao Customs of the People's Republic of China, Shijiazhuang Customs of the People's Republic of China.

1 Scope

This standard specifies the microwave digestion-inductively coupled plasma mass spectrometry method for the determination of various imported iron such as hematite, magnetite, and limonite.

Copper, chromium, manganese, barium, cobalt, thallium, niobium, tantalum, titanium, molybdenum, yttrium, lanthanum, cerium, praseodymium, neodymium, samarium, europium, gadolinium, dysprosium, holmium, Methods for the content of 23 elements such as erbium, thulium, and ytterbium.

This standard is applicable to copper, chromium, manganese, barium, cobalt, thallium, niobium,, copper, chromium, manganese, barium, cobalt, hematite, magnetite, limonite and other imported iron ore.

Determination of 23 elements including tantalum, titanium, molybdenum, yttrium, lanthanum, cerium, praseodymium, neodymium, samarium, europium, gadolinium, dysprosium, holmium, erbium, thulium, and ytterbium. Its determination the range is shown in Table 1.

2 Normative references

The following documents are indispensable for the application of this document. For dated reference documents, only the dated version applies to this article Pieces. For undated reference documents, the latest version (including all amendments) is applicable to this document.

GB/T 602 Preparation of standard solutions for impurity determination of chemical reagents GB/T 6682 Analytical laboratory water specifications and test methods GB/T 8170 Numerical rounding rules and the expression and determination of limit values GB/T 10322.1 Iron ore sampling and sample preparation method

3 Principles of the method

After the sample is digested by microwave, it is introduced into an inductively coupled plasma mass spectrometer for measurement. Using online internal standard, the mass spectrum signal of the element to be measured is compared with the intensity ratio of the internal standard element mass spectrum signal is proportional to the concentration of the element to be measured for quantitative analysis.

4 Reagents and materials

Unless otherwise specified, only use the reagents above the superior grade and the water is the second grade water that meets the requirements of GB/T 6682.

4.1 Hydrochloric acid (rho 1.19 g/mL).

4.2 Hydrofluoric acid (rho 1.30 g/mL).

4.3 Nitric acid (rho 1.42 g/mL).

4.4 Nitric acid solution (2 98, volume ratio). Take an appropriate amount of nitric acid (4.3) and ultrapure water and mix with a volume ratio of 2.98.

4.5 Copper, chromium, manganese, barium, cobalt, thallium, niobium, tantalum, titanium, molybdenum, yttrium, lanthanum, cerium, praseodymium, neodymium, samarium, europium, gadolinium, dysprosium, holmium, erbium, Thulium and Ytterbium standard stock solutions (1 000 µg/mL). Prepare according to GB/T 602 or directly purchase certified reference materials.

4.6 Standard solution series. Use standard stock solution (4.5) to prepare mixed standard working solution series according to Table 2.

4.7 Mass spectrometry tuning solution. 1 µg/L mixed standard solution of lithium, yttrium, cerium, thallium, and cobalt, prepared according to GB/T 602 or directly purchased with a certified standard substance.

4.8 Mixed internal standard solution. 10 mg/L mixed standard solution of scandium, lutetium, indium, bismuth, germanium, rhodium, and terbium, prepared according to GB/T 602 or directly Purchase certified reference materials.

4.9 Internal standard solution (online internal standard solution). take 2.5 mL of mixed internal standard solution (4.8) and dilute to the volume with 2% nitric acid (volume fraction) 50 mL to obtain a standard internal standard solution with a concentration of 500 µg/L.

4.10 Argon gas. purity >= 99.99%.

4.11 Helium. purity >= 99.99%.

5 Apparatus and equipment

5.1 Inductively Coupled Plasma Mass Spectrometer (ICP-MS). equipped with hydrofluoric acid solution atomization injection system. See Appendix A for instrument operating parameters.

5.2 High temperature pressure microwave digestion apparatus. see Appendix B for working parameters.

5.3 Analytical balance. Sensitivity 0.1 mg.

5.4 Pipette. The pipette has a volume of 100 µL, 1,000 µL, and 10 mL.

6 Sample preparation

Prepare the analysis sample according to the provisions of GB/T 10322.1, bake it at 105°C for 2 h, then place it in a desiccator and cool to room temperature spare.

7 Analysis steps

8 Result calculation

The content of the measured element is calculated according to formula (1).

9 Precision

The precision was measured by 8 laboratories on 4 levels of samples, and the data was determined after statistics. The results are shown in Table 3.

Note. X is the average of test results, mg/kg.

Continued

Appendix A

(Informative appendix) Inductively coupled plasma mass spectrometer working parameters and measured elements and internal standard elements to determine the mass number Appendix B (Informative appendix) Working Parameters of Microwave Digestion Apparatus