Methods for chemical analysis of lithium carbonate,lithium hydroxide monohydrate and lithium chloride - Part 10: Determination of chloride content - Silver chloride nephelometry method
1 Scope
This part of GB/T 11064 specifies the methods for determining chloride content in lithium carbonate and lithium hydroxide monohydrate.
This part is applicable to the determination of chloride content in lithium carbonate and lithium hydroxide monohydrate, within the range of 0.0010%~0.10%.
2 Method summary
In nitric acid medium, chloride ions and silver ions generate insoluble silver chloride. With the silver chloride in suspension for a certain time, measure its absorbance at the wavelength of 420 nm by a spectrophotometer to obtain the chloride content.
3 Reagents
Unless otherwise specified, guaranteed reagents and secondary deionized water are used for purpose of this part.
3.1 Nitric acid (1+1).
3.2 Nitric acid (9+16).
3.3 Silver nitrate solution (0.1 mol/L): weigh 17.0 g silver nitrate, put it in a beaker, dissolve with water, transfer into a 1000 mL brown volumetric flask, add drops of nitric acid (3.1) to make the solution transparent, dilute to the scale with water, shake well, and keep it in the dark.
3.4 Sodium hydroxide solution (100 g/L): weigh 10 g sodium hydroxide and put it in a 250 mL plastic beaker, dissolve with 100 mL CO2-free water, and keep it in a plastic bottle.
3.5 P-nitrophenol indicator (1 g/L): analytical grade, prepared with ethanol.
3.6 Chlorine standard storage solution: weigh 1.6484 g sodium chloride (reference substance) which has been ignited to constant weight at 500°C in advance, put it in a 100 mL beaker, dissolve with water, transfer into a 1000 mL volumetric flask, and shake well. This solution contains 1 mg chloride per 1 mL.
3.7 Chlorine standard solution A: take 25.00 mL chloride standard storage solution (3.6), put it in a 250 mL volumetric flask, dilute to the scale with water, and shake well. This solution contains 100 μg chloride per 1 mL.
3.8 Chlorine standard solution B: transfer 25.00 mL chloride standard solution (3.7) into a 500mL volumetric flask, dilute to the scale with water and shake well.
Foreword i
1 Scope
2 Method summary
3 Reagents
4 Apparatus
5 Test sample
6 Analysis procedures
7 Calculation of analysis results
8 Precision
9 Test report
