GB/T 4701.4-1984 Chemical analysis methods for ferrotitanium - Determination of manganese content by the persulfate-arsenite volumetric method GB/T4701.4-1984 standard download decompression password: www.bzxz.net

National Standard of the People's Republic of China
Methods for chemical analysis of ferrotitanium
Methods for chemical analysis of ferrotitaniumThe persulfate-arsenite volumetric method forthe determination of manganese coatentThis standard is applicable to the determination of manganese in ferrotitanium. Determination range: 1.00～4.00% UDC 669.15'295
:543.24-546
GB 4701.4-84
This standard complies with GB1167-78 (General principles and general provisions for chemical analysis methods of metallurgical products). 1 Method Summary
The sample is dissolved in sulfuric acid and hydrochloric acid and sulfuric acid smoke is piped in. With silver nitrate as catalyst, ammonium persulfate is added and boiled to oxidize manganese into permanganate, and titrated with sodium arsenite·sodium nitrite standard solution. 2 Reagents
2.1 Nitric acid (specific gravity 1.42).
2.2 Pan acid (1 → 1).
2.3 Sulfuric acid (1+3).
2.4 Sodium chloride solution (8.5%).
2.5 Silver nitrate solution (0.5%),
2.6 Ammonium persulfate solution (25%), prepare when needed, do not heat when dissolving. 2.7 Mixed acid: 650ml water 4, slowly add 100ml sulfuric acid (specific gravity 1.84), add 250ml nitric acid (2.1) after cooling, mix well.
2.8 Manganese standard solution
2.8.1 Weigh 1.0000g metallic manganese (purity is 99.9%) 2.8.2 Take 10.00ml of the standard solution (2.8.1) and place it in a 100ml beaker, add 20ml of sulfuric acid (1+3), heat to dissolve, remove and cool, transfer to a 1000ml volumetric flask, dilute to scale with water, and mix. This solution contains 1.0mg manganese per ml. 2.8.2 Take 10.00ml of the standard solution (2.8.1) and place it in a 100ml volumetric flask, dilute to scale with water, and mix. This solution contains 0.1mg manganese per ml.
2.9 Sodium arsenite-sodium nitrite standard solution 2.9.1 Preparation
Weigh 0.5000g of high-grade pure arsenic trioxide and dissolve it in 20ml l10% sodium hydroxide solution, dilute with water to 500ml, use 1% phenol ethanol solution as indicator, add sulfuric acid (1+1) until the red color disappears, then add 10% sodium carbonate solution until the red color appears, then add 0.3500g sodium nitrite and dissolve it completely (if it is turbid, it should be filtered). Transfer to a 1000ml volumetric flask, dilute to the scale with water, mix, and store in a brown bottle. This solution is about 0.02. 2.8.2 Calibration
Weigh 0.16g of pure iron without manganese in three portions, place them in 500ml conical flasks respectively, and add manganese standard solution (2. 8.2) (the amount of manganese taken should be close to the amount of manganese in the test solution to be titrated), add 30ml of mixed acid (2.7), heat to dissolve, remove and dilute to 150ml with water, add 10ml of silver nitrate solution (2.5), heat to boil, remove, slowly add 10ml of ammonium persulfate solution (2.6), mix, continue to heat and boil for 1min, remove and cool to room temperature with running water. Add 10ml of sodium chloride solution (2.4), and immediately titrate with sodium nitrite-sodium nitrite solution (2.9) until the red color changes to milky white, which is the end point. At the same time, do a blank test (but do not add manganese standard solution) and calculate the titer of sodium nitrite-sodium nitrite standard solution to manganese according to the following formula. 7
1ml sodium arsenate-sodium nitrite standard solution equivalent to T manganese content, g! The amount of manganese standard solution, more;
—the average volume of sodium arsenate-sodium nitrite standard solution consumed by three portions of manganese standard solution (if the range value exceeds 0.10ml
, it should be recalibrated), ml;
Yol—the volume of sodium arsenate-sodium nitrite standard solution consumed in the blank test during calibration, ml. 3 SampleWww.bzxZ.net
The sample should pass through a 0.125mm sieve.
4 Analysis steps
4.1 Sample amount
Weigh 0.5000g of sample.
4.2 Blank test
Carry out a blank test with the sample.
4.3 Determination
4.3.1 Place the sample (4.1) in a 300ml beaker, add 30ml sulfuric acid (2.3) and 10ml hydrochloric acid (2.2); cover with a beaker, heat until the sample is completely dissolved, add 3ml nitric acid (2.1) for oxidation, and continue heating until concentrated sulfuric acid smoke emerges. 4.3.2 Remove and cool, add 50ml water, heat to dissolve soluble salts, filter with qualitative filter paper, wash with hot water, transfer the filtrate and washing liquid to a 250ml volumetric flask, cool to room temperature, dilute to scale with water, and mix well. 4.3.3 Take 50.00ml of the test solution (4.3.2) and place it in a 500ml conical flask. Add 30ml of the mixed acid (2.7), dilute to 150ml with hot water, add 10ml of the silver nitrate solution (2.5), heat to boiling, remove, slowly add 10ml of the ammonium persulfate solution (2.6), continue heating to boiling for about 1min, so that manganese turns into permanganate, remove and cool to room temperature with running water. 4.3.4 Add 10ml of sodium chloride solution (2.4), and immediately titrate with sodium nitrite-sodium nitrite standard solution (2.9.1) until the pink color changes to milky convex color, which is the end point.
5 Calculation of analysis results
Calculate the manganese content according to the following formula:
Where: T
Mn(%) =
T. (V1-V2)
-1ml sodium arsenite-sodium nitrite standard solution equivalent to manganese, more than 100
-volume of sodium arsenite-sodium nitrite standard solution consumed when titrating the test solution, ml; V2-volume of sodium arsenite-sodium nitrite standard solution consumed in titrating the sample blank, ml; mg
-sample volume, more than:
test solution fraction ratio.
Analysis results are expressed to two decimal places. 6 Allowable difference
The difference in analysis results between laboratories should not be greater than the allowable difference listed in the following table. Additional remarks:
1.00 ~2.00
2.00~ 4.00
GB 4701.4—84
This standard was proposed by the Ministry of Metallurgical Industry of the People's Republic of China. This standard was funded by Jinzhou Ferroalloy Factory of the Ministry of Metallurgical Industry. Supplementary information
From the date of implementation of this standard, the original Ministry of Metallurgical Industry Standard YB581-65 "Chemical Analysis Method of Ferrotitanium" shall be invalidated.
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