GB/T 4701.3-1984 Chemical analysis methods for ferrotitanium - Determination of copper content by the copper reagent photometric method

GB/T 4701.3-1984 Chemical analysis method for ferrotitanium - Determination of copper content by photometric method with copper reagent GB/T4701.3-1984 standard download decompression password: www.bzxz.net

National Standard of the People's Republic of China
Methods for chemical analysis of ferrotitanium The DDTC photometric method for the determination of copper content UDC669.15'295
:543.4-546
GB 4701.3—84
This standard is applicable to the determination of copper content in ferrotitanium. The determination range is 0.10～1.00%. This standard complies with GB1467-78 "General Principles and General Provisions for Chemical Analysis Methods of Metallurgical Products". Method summary
The sample is dissolved in nitric acid and hydrofluoric acid, and citric acid is added to mask the interfering elements such as iron and titanium. In the ammonia solution, sodium diethyldithiocarbamate (DDTC) is added to copper to form an insoluble brown colloidal solution. After adding the gum arabic solution, the absorbance is measured at a wavelength of 460nm using a photometer.
2 Reagents
2.1 Urea.
2.2 Hydrofluoric acid (specific gravity 1.15).
2.3 Nitric acid (2 + 1).
2.4 Ammonium hydroxide (1 + 1).
2. 6 Boric acid solution (5%).
2.6 Ammonium citrate solution (50%).
2.7 DDTC solution (0.2%).
2.: Gum arabic solution (1%). Weigh 2g of gum arabic, dissolve it in 100ml of hot water, add small grains of thymol, filter it with absorbent cotton, dilute it to 200ml with water, and mix it. 2.9 Copper standard solution: Weigh 0.5000g of copper (purity is more than 99.9%), place it in a 200ml beaker, add 30ml of nitric acid (3+5), heat to dissolve and boil to remove nitrogen oxides, cool to room temperature, transfer it to a 1000ml volumetric flask, dilute it to the scale with water, and mix it. This solution contains 0.5mg of steel per ml.
8 Instruments
Spectrophotometer.
4 Sample
The sample should pass through a 0.125mm sieve.
5 Analysis steps
6.1 Sample quantity
Weigh 0.2500g of sample.
5.2 Blank test
National Bureau of Standards 1984-10-04 Issued
1985-09-01 Implementation
Blank test is performed on any sample.
GB4701.3—84
5.3 Determination
5.3.1 Place the sample (5.1) in Ⅲ, add 18ml nitric acid (2.3), heat to 60~70℃, drop 1ml hydrofluoric acid (2.2) to completely dissolve the sample, add 25m boric acid solution (2.5), mix well, cool to room temperature, transfer to a 50ml volumetric bottle, dilute to the mark with water, and mix well.
5.3.2 Take two portions of 10.00ml solution (5.3.1), place them in ten 50ml volumetric bottles, add 0.2g of sodium fluoride (2.1) to each, and shake to dissolve it.
5.8.3 Add 5 ml of ammonium citrate solution (2.6), 5 ml of gum arabic solution (2.8) and 10 ml of ammonium hydroxide (2.4) to one portion of the solution, dilute to the mark with water and mix. 5.3.4 Add 5 ml of ammonium citrate solution (2.6), 5 ml of gum arabic solution (2.8) and 10 ml of ammonium hydrocyanide (2.4) to another portion of the solution, add 5 ml of DDTC solution (2.7) under constant shaking, dilute to the mark with water and mix. 5.3.5 Transfer part of the solution (5.3.4) to an appropriate colorimetric medium, use the solution (5.3.3) as a reference, measure its absorbance at a wavelength of 460 nm on a spectrophotometer, subtract the absorbance of the blank test accompanying the sample, and find the corresponding copper content from the working curve. 5.4 Drawing of working curve
Weigh 7 portions of 0.2500g titanium iron (without copper) test sample, add 0, 0.50, 1.00, 2.00, 3.00, 4.00, 5.00ml of copper standard solution (2.9) to a group of solution 1, respectively, and proceed as per 5.3.1 to 5.3.6. Measure its absorbance, subtract the absorbance of the reagent blank test, and draw a curve with copper as the horizontal axis and absorbance as the vertical axis. 6 Calculation of analysis results
Calculate the percentage of copper according to the following formula:www.bzxz.net
Cu(%) =
Where: ml-the amount of copper found on the working curve, g,m-the amount of sample, g!
-the ratio of test solution.
The analysis results are expressed to two decimal places. 1 Allowable difference
The difference between the analysis results of laboratories should not be greater than the allowable difference listed in the following table. Copper
0.10~0.30
>0.30~0.60
>0.60~1.00
Additional remarks:
This standard is proposed by the Ministry of Metallurgical Industry of the People's Republic of China. This standard is initiated by Jinzhou Ferroalloy Factory of the Ministry of Metallurgical Industry. ×100
Allowable difference
From the date of implementation of this standard, the former Ministry of Metallurgical Industry Standard YB581-65 "Chemical Analysis Method of Ferrotitanium" shall be invalidated.
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