YS/T 239.5-2010Methods for chemical analysis of antimony trisulfide. Part 5: Determination of arsenic content. Arsenic molybdenum blue spectrophotometric method (English PDF)

Foreword

YS/T 239 "Methods for chemical analysis of antimony trisulfide" There are seven sections.

--- Part 1. Determination of antimony content cerium sulfate titration;

--- Part 2. Determination of the amount of sulfur compounds and combustion titration method;

--- Part 3. Determination of free sulfur content and combustion titration method;

--- Part 4. aqua regia insolubles - Gravimetric method;

--- Part 5. Determination of arsenic content of arsenic molybdenum blue spectrophotometric method;

--- Part 6. Determination of iron content of phenanthroline spectrophotometry;

--- Part 7. Determination of lead content by flame atomic absorption spectrometry.

This is Part 5.

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

Division into new parts.

This standard by the national non-ferrous metals Standardization Technical Committee (SAC/TC243) centralized.

1 Scope

This section YS/T 239 specifies the method for determination of arsenic, antimony trisulfide amount.

This section applies to the determination of arsenic, antimony trisulfide amount. Measurement range. 0.010% mass fraction of arsenic to 0.25%.

2 Method summary

Sample was dissolved with sulfuric acid, hydrochloric acid solution in not less than 9mol/L, the arsenic trichloride was extracted with benzene to coexist with the substrate, and other miscellaneous Mass separation. After back-extracted with water and oxidized to pentavalent arsenic and arsenic, plus ammonium molybdate and hydrazine sulfate generate arsenic molybdenum blue wavelength spectrophotometer Measuring the absorbance at 660nm.

3 Reagents

Unless otherwise indicated, the reagents used in this section refer to water and recognized analytical reagent and tertiary water.

3.1 sulfate (rho1.84g/mL).

3.2 hydrochloride (rho1.19g/mL).

3.3 benzene.

3.4 sulfate (120).

3.5 sulfate (11).

Sulfite 3.6 (12).

3.7 Sodium hydroxide solution (300g/L). stored in a plastic bottle.

3.8 Sodium hydroxide solution (50g/L). stored in a plastic bottle.

3.9 iodine solution (5g/L). Weigh 0.5g iodine, 1g of potassium iodide in 250mL beaker, 5mL water was added to dissolve, dilute to 100mL, stored in a brown bottle.

3.10 ammonium molybdate solution (15g/L). Weigh 1.5g of ammonium molybdate [(NH4) 6Mo7O24 · 4H2O] placed in 250mL beaker, add 40mL water, add 50mL sulfuric acid (3.5), transferred to a glass bottle after cooling. Diluted with water to 100mL, and mix.

3.11 hydrazine sulfate solution (0.5g/L).

3.12 phenolphthalein indicator (1g/L ethanol).