YS/T 226.9-2009Methods for chemical analysis of selenium. Part 9: Determination of iron content. Flame atomic absorption spectrometry (English PDF)

Foreword

YS/T 226 "selenium chemical analysis method" is divided into 13 parts.

--- Part 1. Determination of bismuth content - Hydride Generation - Atomic Fluorescence Spectrometry

--- Part 2. Determination of antimony content Hydride Generation - Atomic Fluorescence Spectrometry

--- Part 3. Determination of aluminum content Chromazurol S- cetylpyridinium bromide spectrophotometric method

--- Part 4. Determination of mercury content of dithizone - CTC colorimetric titration

--- Part 5. Determination of the amount of silicon molybdenum blue spectrophotometry

--- Part 6. Determination of sulfur content symmetrical diphenyl semicarbazide spectrophotometry

--- Part 7. Determination of magnesium content - Flame atomic absorption spectrometry

--- Part 8. Determination of copper content - Flame atomic absorption spectrometry

--- Part 9. Determination of iron content by flame atomic absorption spectrometry

--- Part 10. Determination of nickel content by flame atomic absorption spectrometry

--- Part 11. Determination of lead content by flame atomic absorption spectrometry

--- Part 12. Determination of the amount of selenium sodium thiosulfate volumetric method

--- Part 13. silver, aluminum, arsenic, boron, mercury, bismuth, copper, cadmium, iron, gallium, indium, magnesium, nickel, lead, silicon, antimony, tin, tellurium, titanium, zinc contents Inductively Coupled Plasma Mass Spectrometry this section YS/T Section 9226 of.

The measured partial replacement of YS/T 226.11-1994 "selenium magnesium, copper, iron, nickel content by flame atomic absorption spectrometry" iron content Given portion. Compared with YS/T 226.11-1994, this section has the following main changes.

--- Supplementary terms of quality assurance and control;

--- Increase the repeatability limit, will be allowed to poor reproducibility limit.

The non-ferrous metal part by the National Standardization Technical Committee and centralized.

This section is responsible for drafting unit. Jinchuan Group Limited.

Participated in the drafting of this section. Beijing Nonferrous Metal Research Institute, Guangzhou Nonferrous Metal Research Institute.

1 Scope

This section YS/T 226 specifies the method for determination of selenium in iron content.

This section applies to the determination of selenium in iron content. Measurement range. 0.0005% to 0.06%.

2 Method summary

Sample decomposition with nitric acid at 320 °C volatile removing selenium, 3% hydrochloric acid medium, with air - acetylene flame at the wavelength 248.3nm (Or 372.0nm) measuring the absorbance of iron, according to the working curve method to calculate the amount of iron.

3 Reagents

Unless otherwise indicated, the second part of the water are distilled water, reagents were pure class distinctions.

Nitrate 3.1 (rho1.42g/mL).

3.2 hydrochloride (rho1.19g/mL).

3.3 hydrochloric acid (1 + 2).

3.4 iron standard stock solution. Weigh 0.1000g iron (iron mass fraction >=99.5%), placed in 250mL beaker, add 20mL salt Acid (3.2), 3% hydrogen peroxide solution of 3-5 drops dissolved by heating, the solution was evaporated to a volume of about 10mL removed and cooled. Transferred to 100mL capacity Volumetric flask, dilute to the mark, shake. 1mL solution containing 1mg iron.

3.4.1 Iron Standard Solution A. Pipette 10.00mL iron standard stock solution (3.4), placed in 100mL flask, add 3mL hydrochloric acid (3.2), diluted with water to the mark. This solution 1mL containing 100µg iron.

3.4.2 Iron standard solution B. Pipette 20.00mL iron standard stock solution (3.4), placed 1000mL volumetric flask, add 15mL hydrochloric acid (3.2), diluted with water to the mark. This solution 1mL containing 20µg iron.

4 Instrument

4.1 Atomic absorption spectrometer, with iron hollow cathode lamp.

Under optimum working conditions for those who can reach the following indicators can be used.

--- Characteristic concentration. the test solution is consistent with the measurement of the solution, the characteristic concentration of iron is not more than 0.1µg/mL.

--- Precision. standard solution with the highest concentration of 10 times the absorbance measurements, the standard deviation should not exceed the average absorbance of 1.0%;

The lowest concentration of standard solution used (instead of "zero" standard solution) absorbance measured 10 times, and the standard deviation should not exceed the maximum concentration 0.5% of the mean absorbance of standard solution.

--- Linear curve. The curve is divided into five sections according to concentration, absorbance difference between the absorbance difference between the highest and the lowest segment of the segment Ratio of not less than 0.85.

Atomic absorption spectrometer operating conditions refer to Table 1.

Table 1 instrument conditions

Wavelength/nm lamp current/mA monochromator passband/nm observation height/mm flame type 248.3/372.0 7 0.2 7 stoichiometric flame