GB/T 5059.2-1985 Chemical analysis methods for ferromolybdenum - Malachite green spectrophotometric method for determination of antimony content

This standard is applicable to the determination of antimony content in ferromolybdenum. Determination range: 0.005~0.120%. This standard complies with GB 1467-78 "General Principles and General Provisions of Chemical Analysis Methods for Metallurgical Products". GB/T 5059.2-1985 Chemical analysis method for ferromolybdenum Malachite green spectrophotometric method for determination of antimony content GB/T5059.2-1985 Standard download decompression password: www.bzxz.net

National Standard of the People's Republic of China
Methods for chemical analysis of ferromolybdenumThe malachite green spectrophotometric methodfor the determination of antimony contentThis standard is applicable to the determination of antimony content in ferromolybdenum. Determination range: 0.005～0.120%. This standard complies with GB1467-78 "General Principles and General Provisions for Chemical Analysis Methods of Metallurgical Products". 1 Method Summary
UDC 669.15'28
: 543.42 : 546
GB5059.2--85
The sample is dissolved with nitric acid, white smoke is emitted when treated with sulfuric acid, salts are dissolved with hydrochloric acid, tin dichloride is added to the acid solution to reduce antimony to trivalent, then trivalent antimony is oxidized to pentavalent with sodium nitrate, excess sodium nitrite is destroyed with urea, malachite green is added to form a green complex with pentavalent antimony, and the absorbance is measured with benzene. 2 Reagents
2.1 Nitric acid (1+3).
2.2 Hydrochloric acid (1+1).
Sulfuric acid (1+1).
Sulfuric acid (1+8).
Stannic chloride solution (10%): Weigh 10g tinnic chloride, dissolve in 100ml hydrochloric acid (2.2) 1, mix. 2.61
Sodium nitrite solution (10%).
2.7Urea solution: Weigh 50g urea, dissolve in 50ml hot water, mix. Cool to room temperature. 2.8
Malachite green solution (0.5%): Weigh 0.5g malachite green, dissolve in 100ml ethanol (3+1), mix. Toluene.
2.10 Antimony standard solution
2.10.1 Weigh 0.1 pure antimony, dissolve in 50ml sulfuric acid (specific gravity 1.84), add 50ml sulfuric acid (specific gravity 1.84), cool. Transfer to a 1000ml volumetric flask pre-filled with 600ml water, dilute to scale with water, and mix. 1 ml of this solution contains 0.1 mg of antimony. 2.10.2 Take 10.00 ml of antimony standard solution (2.10.1), place it in a 500 ml volumetric flask, dilute to the mark with sulfuric acid (2.4), and mix well. 1 ml of this solution contains 2 ug.
3 Instrument
Spectrophotometer.
4 Sample
The sample should pass through a 0.125 mm sieve
5 Analysis steps
5.1 Sample
National Bureau of Standards 1985-04-15 Issued
198601-01 Implementation
Weigh 0.2000 g of sample.
5.2 Blank test
Carry out a blank test with the sample.
5.3 Determination
GB5059.2--85
5.3.1 Place the sample (5.1) in a 250ml beaker, add 20ml nitric acid (2.1), cover with meter III, slowly heat to dissolve the sample, after the sample is dissolved, add 10ml sulfuric acid (2.3), evaporate and emit white smoke, cool. Wash the wall of the cup with water and reheat until smoke appears, dissolve the salt with 80ml hydrochloric acid (2.2), transfer the solution to a 100ml volumetric flask, wash the beaker with hydrochloric acid (2.2) and dilute the solution to the scale, mix well.
5.3.2 Transfer 10.00ml of the solution and place it in a 150ml separatory funnel. Add hydrochloric acid (2.2) to make the solution volume 20ml, add 10ml sulfuric acid (2.3), and cool. Add 1ml tin dichloride solution (2.5), 2ml sodium nitrate solution (2.6), shake for 5min, add 1ml urea solution (2.7), 70ml water, 1.00ml malachite green solution (2.8), shake 2 or 3 times, add 20ml toluene (2.9), shake for 1min, discard the water layer after separation, transfer the toluene layer to colorimetric III, use methyl methacrylate as reference, and measure its absorbance at a wavelength of 640nm on a spectrophotometer.
5.3.3 Subtract the absorbance of the blank test performed with the sample, and find out the corresponding antimony amount from the working curve. 5.4 Drawing of working curve
Put 0.00, 1.00, 3.00, 5.00, 7.00, 9.00, 12.00 ml of standard solution (2.10.2) into a set of 250 ml beakers, add 20 ml of nitric acid (2.1) and 10 ml of sulfuric acid (2.3), evaporate until sulfuric acid smoke appears, and cool. Wash the beaker wall with water and evaporate again until white smoke appears, add 10 ml of hydrochloric acid (2.2), and transfer the solution into a 150 ml separatory funnel. Proceed as in 5.3.2. Subtract the absorbance of the reagent blank. Draw the working curve with the amount of antimony as the horizontal axis and the absorbance as the vertical axis. 6 Calculation
Calculate the percentage of antimony as follows:
Sb(%)
Where: m--the antimony value obtained by drawing a curve from 1, g; mo--the sample volume, B,
-the sample solution fraction ratio.
The analysis result is accurate to the third decimal place. 7 Allowable difference
The difference in the analysis results between laboratories should not be greater than the allowable difference listed in the following table. %
Allowable difference
0.005 ~0.008
~0.008~0.020
0.020~0.050
0.050 -0.120
Additional instructions:
GB5059.2-85wwW.bzxz.Net
This standard is proposed by the Ministry of Metallurgy of the People's Republic of China. This standard was drafted by the Jilin Ferroalloys Department of the Metallurgical Industry. From the date of implementation of this standard, the original Metallurgical Industry Department Standard YB580-65 "Chemical Analysis Method of Ferromolybdenum" will be invalid.
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