GB/T 4375.8-1984 Chemical analysis method for gallium - Determination of indium content by ethyl violet photometry GB/T4375.8-1984 standard download decompression password: www.bzxz.net

National Standard of the People's Republic of China
Methods for chemical analysis of gallium The ethyl violet photometric method for the determination of indium content This standard applies to the determination of gallium indium. Determination standard: 0.00050～0.040% UDC 669.871: 543
. 42: 546.682
GB 4375.8—84
This standard complies with GB1467-78 "General Principles and General Provisions of Chemical Analysis Methods for Metallurgical Products". 1 Method Summary
The sample is dissolved in nitric acid and sulfuric acid, and hydrobromic acid is added. Tin, tin and other bromides are removed with sulfuric acid fumes. Potassium iodide and ethyl violet are added to 3N sulfuric acid medium to form an ion complex with indium, which is extracted with benzene. 」Measure its absorbance at a wavelength of 619nm with a spectrophotometer. This method is not applicable if gallium contains thallium.
2 Reagents
2.1 Benzene.
2.2 Anhydrous ethanol.
2.3 Nitric acid (specific gravity 1.42).
2.4 Hydrobromic acid (specific gravity 1.49).
Sulfuric acid (+1). Www.bzxZ.net
Sulfuric acid (1+2).
Potassium iodide solution (6M): prepare it when used. 2.8
Sodium thiosulfate solution (2%).
2.9 Ethyl violet solution (0.2%).
2.10 Standard stock solution of steel: Weigh 0.1209g of steel oxide (99.9% or more), add 10ml of hydrochloric acid (1+1), heat on a water bath to dissolve, add 50ml of sulfuric acid (2.5) and evaporate to a smoky state, remove and cool, dissolve the salts with water and transfer to a 1000ml volumetric flask, dilute to scale with water, and mix. This solution contains 100μg of steel in 1ml. 2.11 Standard stock solution of steel: Transfer 50.00ml of standard stock solution of steel (2.10), place in a 500ml volumetric flask, add 10ml of sulfuric acid (1+1), dilute to scale with water, and mix. This solution contains 10μg of steel in 1ml. 3 Instruments
Spectrophotometer.
4 Analysis steps
4.1 Determination quantity
Weigh two samples for determination and take the average value. 4.2 Sample quantity
Weigh the sample according to Table 1.
National Bureau of Standards 1984-04-30 Issued
1985-04-01 Implementation
4.3 Determination
0.H050~0.0010
0.0010 ~ 0.010
-0.010~0.040
GB4375.8-84
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4.3.1 Place the sample (4.2) in a 100ml beaker, add 5ml nitric acid (2.3), cover with Table III, heat at low temperature for a while, add 25ml sulfuric acid (2.5), heat until the sample is completely dissolved. Cool slightly, rinse Table III l with water, and evaporate the solution until it is completely fuming. Cool slightly, add a little water along the wall of the cup! 1ml hydrobromic acid (2.4), stir, and evaporate until white smoke appears. Cool, rinse the cup with water and add a small amount of water, mix. Transfer to a 100ml container, dilute to the mark with water, and mix. 4.3.2 Transfer 10.00ml solution (4.3.1), place in a 50ml separatory funnel, add 3ml potassium iodide solution (2.7), mix. Add 0.5ml sodium thiosulfate solution (2.8), mix. Add 1.5ml ethyl violet solution (2.9), mix. Add 10.00ml benzene (2.1), shake vigorously for 30s. After standing and stratification, discard the aqueous phase. Transfer the organic phase to a dry colorimetric tube, add 5 drops of anhydrous ethanol (2.2), and mix.
4.3.3 Pipette part of the solution (4.3.2) into a 1 cm colorimetric III, use the reagent blank as a reference, measure its absorbance at a wavelength of 619 nm on a spectrophotometer, and extract the corresponding steel from the curve. 4.41 Plotting the curve
4.4.1 Pipette 0, 0.20, 0.40, 0.60, 0.80, 1.00 ml of the steel standard solution (2.11), place them in 50 ml separatory funnels, add 3.7 ml of sulfuric acid (2.6), dilute to 10 ml with water, and mix. Add 3 ml of potassium iodide solution (2.7), and proceed as per 4.3.2 from the addition of 0.5 ml of sodium thiosulfate solution (2.8) to 4.3.3. 4.4.2 Take part of the solution (4.4.1) and place it in a 1 cm colorimetric medium. Take the reagent air as reference and measure its absorbance at a wavelength of 619 nm on a spectrophotometer. Plot the I curve with the amount of steel as the abscissa and the absorbance as the ordinate. 5 Calculation of analysis results
Calculate the steel content according to the following formula:
In (%) =
Formula: m
mo·Vi × 10
Steel content found on the I curve, μg; - total volume of test solution, ml,
, - volume of test solution taken, ml;
6 Allowable difference
Maximum sample volume, g.
The difference in analysis results between laboratories should not be greater than the allowable difference listed in Table 2. × 100
Additional Notes:
0. 0005 - 0. 0020
>0.0020~0.0050
:- 0.0050 ~0.0090
0.009~0.020
>0.020~0.040
GB4375.8—84
This standard was proposed by China National Nonferrous Metals Corporation. This standard was drafted by the Nonferrous Metals Research Institute of China National Nonferrous Metals Corporation. The main drafter of this standard is Zang Muwen.
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