HG/T 2516-1993 Chemical composition analysis method of vanadium catalyst for sulfuric acid production
Some standard content:
Chemical Industry Standard of the People's Republic of China
HG/T 2516—93
Vanadium catalyst for sulfuric acid production
Chemical composition analysis method
Issued on September 9, 1993
Ministry of Chemical Industry of the People's Republic of China
Implementation on July 1, 1994
Chemical Industry Standard of the People's Republic of China
Vanadium catalyst for sulfuric acid production
Chemical composition analysis method
1 Subject content and scope of application
HG/T2516—93
Replaces HG/T1—-1431-—81
This standard specifies the chemical composition analysis method for vanadium catalysts for sulfuric acid production of types S101, S107, S108, S109 and other types with the same chemical composition.
This standard is applicable to the content range of the components to be tested: vanadium pentoxide is 5%~10%; potassium sulfate is 15%~25%; sodium sulfate is 1%~15%; phosphorus pentoxide is 0.5%~35%; antimony trioxide is 0.5%~3%; ferric oxide is 0.2%~2%; silicon dioxide is>50%,
2 Reference standards
GB/T601 Preparation of standard solutions for titration analysis (volumetric analysis) of chemical reagents GB/T603 Preparation of preparations and products used in test methods of chemical reagents GB/T6682 Specifications and test methods for water used in analytical laboratories 3 Reagents and materials
The reagents and purity used in this standard are all analytical pure reagents unless otherwise specified; the water used for experiments should meet the specifications of grade 3 water in GB/T6682.
4 Preparation of sample
Mix the laboratory sample evenly, take about 40g by quartering, crush and grind it all in a porcelain mortar, take about 20g by quartering again, continue to grind until the sample can pass through the 150um test sieve, place it in a weighing bottle, dry it at 105~110℃ for 2h, place it in a desiccator and cool it to room temperature for use.
5 Preparation of sample solution
5.1 Preparation of sample solution A of vanadium catalyst for S101, S107, S108 type sulfuric acid production 5.1.1 Summary of method
The sample is decomposed by perchloric acid and hydrofluoric acid, silicon escapes into silicon tetrafluoride, and salts are dissolved in water. 5.1.2 Reagents and solutions
5.1.2.1 Perchloric acid (GB/T623).
5.1.2.2 Hydrofluoric acid (GB/T620).
5.1.3·Operation steps
Weigh about 2.5g of sample, accurate to 0.0001g, place in a 150mL platinum dish, and moisten with water. Add 10mL perchloric acid and about 30mL hydrofluoric acid, place on a sand bath and heat to evaporate until thick pernitrogen acid white smoke appears, remove and cool slightly, add 50~60mL of water, heat to dissolve the salt, filter into a 250mL volumetric flask, wash the platinum dish and filter paper with hot water 7~8 times, dilute with water to about 220mL, shake well, cool to room temperature, dilute with water to the scale, and shake well. This solution is sample solution A. Approved by the Ministry of Chemical Industry of the People's Republic of China on September 9, 1993 and implemented on July 1, 1994
HG/T2516—93
5.2 Preparation of Sample Solution B of Vanadium Catalyst for S109 Sulfuric Acid Production 5.2.1 Method Summary
The sample is treated with sulfuric acid and hydrofluoric acid, and silicon escapes as silicon tetrafluoride. In a concentrated sulfuric acid medium, filter paper is used as a reducing agent to completely decompose the sample, and the salts are dissolved with water.
5.2.2 Reagents and Solutions
5.2.2.1 Sulfuric acid (GB/T625) solution: 1+1.5.2.2.2 Hydrofluoric acid (GB/T620).
5.2.3 Operation Steps
Weigh about 2.5g of sample, accurate to 0.0001g, place in 150mL of platinum III, and moisten with water. Add 50mL of sulfuric acid solution (5.2.2.1) and about 30mL of hydrofluoric acid, place on a sand bath, heat and evaporate until thick sulfur trioxide white smoke emerges, remove, and cool. Use a small amount of water to transfer the contents of the dish to a 250mL conical flask, then wipe the platinum dish with one-eighth of a piece of filter paper (Φ11cm), put the filter paper into the conical flask, and then wash the platinum dish with water. Steam the conical flask on a hot plate until thick white smoke comes out, cover it with Table III, continue to heat until the solution is clear brown-green (there is a small amount of brown-yellow precipitation at the bottom of the bottle), remove it, and cool it. Blow the blood on the table with water, add about 100mL of water, heat to completely dissolve the salts, transfer it to a 250mL volumetric flask, cool it, dilute it to the scale with water, shake it well, and filter it if necessary. This solution is the test solution B.5.3 Preparation of test solution C for the determination of vanadium pentoxide content by alkali fusion method 5.3.1 Principle of the method
The test sample is melted with sodium hydroxide, extracted with water, and acidified with sulfuric acid. 5.3.2 Reagents and solutions
5.3.2.1 Sodium hydroxide (GB/T629).
5.3.2.2 Sulfuric acid (GB/T625) solution: 1+15.3.3. Operation steps
Weigh about 1g of sample, accurate to 0.0001g, place in 50mL nickel, add 6~8g of sodium hydroxide, cover with glass, place in a high-temperature furnace, gradually heat to 450~500℃, and melt for 15min. Take out, cool, place in a 250mL beaker, add about 50mL of hot water to extract the molten material, and wash the crucible with hot water. Add sulfuric acid solution (5.3.2.2) dropwise to acidify the solution, and add 50mL in excess to control the total volume to about 150mL, cool to room temperature, and this solution is sample solution C. 6 Determination of vanadium pentoxide content Ammonium ferrous sulfate titration method (arbitration method) 6.1 Summary of the method
In a sulfuric acid medium with a c(H,SO) of about 3mol/L, potassium permanganate is used to oxidize tetravalent vanadium to pentavalent vanadium. In the presence of urea, reduce excess potassium permanganate with sodium nitrite, use phenylanthranilic acid as an indicator, and titrate with ammonium ferrous sulfate standard titration solution.
6.2 Reagents and solutions
6.2.1 Sulfuric acid (GB/T625) solution: 1+1.6.2.2 Phosphoric acid (GB/T1282).
6.2.3 Potassium permanganate (GB/T643) solution: 3g/L. 6.2.4 Urea (GB/T696) solution: 200g/L. 6.2.5 Sodium nitrite (GB/T633) solution: 10g/L. 6.2.6 Ammonium ferrous sulfate (GB/T661) standard titration solution: c<(NH4),Fe(SO4))=0.1mol/L, prepared and calibrated according to GB/T601.
6.2.7 Phenylanthranilic acid indicator solution: 2g/L Weigh 0.20g of phenylanthranilic acid and 0.20g of anhydrous sodium carbonate (GB/T639) and dissolve them in water, then dilute with water to 100mL.
HG/T2516-93
6.3 Analysis steps
Pipette 100.0mL of sample solution A (5.1), place it in a 250mL beaker, add 50mL of sulfuric acid solution (6.2.1), and cool to room temperature;
Or pipette 100.0mL of sample solution B (5.2), place it in a 250mL beaker, add 25mL of sulfuric acid solution (6.2.1), and cool to room temperature;
If the sample solution is prepared according to Section 5.3 of this standard, take all the sample solution C. Add 5mL of phosphoric acid to the above solution, add potassium permanganate solution dropwise until the solution turns a stable rose red, stir well, and let stand for 10 minutes. Add 5 mL of urea solution, and add sodium nitrite solution drop by drop while stirring continuously until the red color just disappears and there is 1-2 drops of excess. Stir thoroughly, let stand for 1 min, add 3 drops of phenylanthranilic acid indicator solution, and titrate with ammonium ferrous sulfate standard titration solution until the solution changes from purple-red to bright green, which is the end point. 6.4 Expression of analytical results
The mass percentage of vanadium pentoxide (X,%) is calculated according to formula (1): X, =C: V×0. 090 94
Wherein: V—volume of standard ammonium ferrous sulfate solution consumed in titration, mL; actual concentration of standard ammonium ferrous sulfate solution, mol/L; (1)
The mass of the sample taken, g;
0.09094—the mass of vanadium pentoxide equivalent to 1.00 mL of standard ammonium ferrous sulfate solution [c[(NH)Fe(SO),）=1.000 mol/L), expressed in grams. 6.5 Allowable difference
The absolute difference between the results of two parallel determinations shall not exceed 0.2%. 7 Determination of vanadium pentoxide content Potassium permanganate titration method (This method is not applicable to S109 type) 7.1 Method summary
In a sulfuric acid medium with c(H,SO.)=3mol/L, use excess ferrous iron to reduce pentavalent vanadium in the sample solution to tetravalent vanadium. Using 1,10-phenanthroline-ferrous iron as an indicator, use potassium permanganate standard titration solution to oxidize excess ferrous iron. In cHSO4)≤1.75 mol/L, 60~80℃, use potassium permanganate standard titration solution to titrate tetravalent vanadium. 7.2 Reagents and solutions
7.2.1 Sulfuric acid (GB/T625) solution: 1+1.7.2.2 Phosphoric acid (GB/T1282).
7.2.3 Ammonium ferrous phosphate (GB/T661) solution: c((NH)Fe(SO))=0.1 mol/L, prepared according to GB/T601.
7.2.4 Potassium permanganate (GB/T643) standard titration solution: c(KMnO)=0.1 mol/L, prepared and calibrated according to GB/T601.
7.2.51, 10-phenanthroline (C12H.Nz·HzO, GB/T1293)-ferrous indicator solution: prepared according to GB/T603. 7.3 Analysis steps
Pipette 100.0mL of sample solution A (5.1) and place it in a 400mL beaker. Add 50mL of sulfuric acid solution (7.2.1), cool to room temperature, add 2 drops of 1,10-phenanthroline-ferrous indicator solution, add ammonium ferrous sulfate solution to turn orange-red, and add 1-2mL excess, add 5mL of phosphoric acid, and titrate with potassium permanganate standard titration solution until the orange-red color just fades and turns blue-gray, add about 170mL of hot water, heat to 70-80℃, and immediately titrate with potassium permanganate standard titration solution until it turns slightly red and does not fade for about half a minute as the end point. Record the volume of potassium permanganate standard titration solution consumed during the second titration. 3
7.4 Expression of analysis results
HG/T2516-93
The mass percentage of vanadium pentoxide (X,%) is calculated according to formula (2): X,
V:cx0.09094
Wherein: V-the volume of potassium permanganate standard titration solution consumed in the second titration, mL; the actual concentration of potassium permanganate standard titration solution, mol/L; the mass of the sample taken, g;
0.09094-the mass of vanadium pentoxide expressed in grams equivalent to 1.00mL potassium permanganate standard titration solution (c (一KMnO) = 1.000mol/L).
7.5 Allowable difference
The absolute difference between the results of two parallel determinations shall not exceed 0.2%. 8 Determination of potassium sulfate content Tetraphenylborate potassium weighing method (arbitration method) 8.1 Method summary
Add sodium tetraphenylborate solution to the nearly neutral potassium ion sample solution to generate tetraphenylborate potassium precipitate. After washing and drying, weigh the precipitate and calculate the potassium sulfate content. Add citric acid to mask the interference of coexisting antimony ions. 8.2 Reagents and solutions
8.2.1 Sodium hydroxide (GB/T629) solution: 200g/L, stored in polyethylene bottles 8.2.2 Hydrochloric acid (GB/T622) solution: 1+1. 8.2.3 Citric acid (GB/T9855) solution: 100g/L. 8.2.4 Sodium tetraphenylborate (HG/T3-1164) solution: 15g/L Weigh 15g of sodium tetraphenylborate and dissolve it in about 950mL of water, add 8mL of sodium hydroxide solution and 20mL of magnesium chloride (GB/T672) solution (100g/L), add water to 1L, stir evenly and store in a brown glass bottle or plastic bottle. Filter the clear liquid as a precipitant before use. The storage period of this reagent is about one month. 8.2.5 Washing solution: Sodium tetraphenylborate solution (8.2.4) and water are mixed at a ratio of 1+10. 8.2.6 Phenol (GB/T10729) indicator solution: 5g/L ethanol (GB/T678) solution. 8.3 Analysis steps
Pipette 20.00mL of sample solution A (5.1) or sample solution B (5.2) into a 250mL beaker, add 50mL of water, 10mL of citric acid, and 3 drops of phenolic acid indicator solution, add sodium hydroxide solution dropwise under stirring to make the test solution appear red, and add hydrochloric acid solution (8.2.2) dropwise to make the red color fade. Dilute to about 100mL with water, add 30mL of sodium tetraphenylborate solution dropwise under constant stirring, and let stand for 15min
Filter the precipitate into a glass filter dried to constant weight at 120±5℃ by decantation. Wash the precipitate 5~7 times with washing solution (8.2.5), and finally wash it twice with water, using about 8mL each time. Place the crucible with the precipitate in a drying oven at 120 ± 5 ℃ and dry for 1.5 hours. Take it out and put it in a desiccator to cool to room temperature. Weigh it.
Note: When cleaning the glass crucible, soak it with a small amount of acetone first, then filter and wash it with water. 8.4 Expression of analytical results
The mass percentage of potassium sulfate (X, %) is calculated according to formula (3): (m, -m,) × 0. 243 1
Where: mz
-mass of precipitate and crucible, g;
mass of crucible, g;
mass of sample, g;
HG/T2516-93
0.2431——The coefficient for converting the mass of potassium tetraphenylborate into the mass of potassium sulfate. 8.5 Permissible difference
The absolute difference of the parallel determination results shall not exceed 0.3%. 9 Determination of potassium sulfate content Flame photometry
9.1 Method summary
Determine the potassium in the sample solution by flame photometry, and quantify it by the working curve method. 9.2 Reagents and solutions
9.2.1 Hydrochloric acid (GB/T622) solution: 1+1.9.2.2 Sulfuric acid (GB/T625) solution: 1+1.9.2.3 Ammonia (GB/T631) solution: 1+3.9.2.4 Potassium oxide standard solution (1mL solution contains 1.00mgK,0) Weigh 1.583g of potassium chloride (GB/T646, high-grade purity) burned to constant weight at 500-600℃, dissolve it in water, transfer it to a 1000mL volumetric flask, dilute it to the scale with water, shake it well, and store it in a polyethylene bottle. 9.2.5 Methyl orange indicator solution: 1g/L, prepared according to GB/T603. 9.3 Instruments
Flame photometer.
9.4 Analysis steps
9.4.1 Drawing of working curve
Add 0, 1.00, 3.00, 5.00, 7.00 mL of potassium oxide standard solution (9.2.4) to 5 100 mL volumetric flasks respectively, which is equivalent to 0, 1.00, 3.00, 5.00, 7.00 mg of potassium oxide. Add 1.0 mL of hydrochloric acid solution (9.2.1) to each flask. Dilute to the scale with water and shake to obtain standard series solution I;
Add 0, 1.00, 3.00, 5.00, 7.00 mL of potassium oxide standard solution (9.2.4) to 5 100 mL volumetric flasks respectively, which is equivalent to 0, 1.00, 3.00, 5.00, 7.00 mg of potassium oxide. Add 1.0 mL of sulfuric acid solution (9.2.2) to each flask. Dilute to the scale with water to obtain standard series solution D.
On a flame photometer, with water as reference, determine the emission intensity of the potassium spectrum of the standard series solution, with the obtained indication value as the ordinate and the corresponding potassium oxide mass as the abscissa, and draw working curves I and II. 9.4.2 Determination
9.4.2.1 Take 5.00mL of sample solution A (5.1) and place it in a 100mL volumetric flask, add 1 drop of methyl orange indicator solution, add ammonia solution (9.2.3) to neutralize until the solution turns yellow, add 1.0mL of hydrochloric acid solution (9.2.1), dilute with water to the scale, and shake well. Determine the emission intensity of the potassium spectrum under the same conditions as the standard series solution I, and find the corresponding potassium oxide mass from the working curve I according to the indication value of the measured solution.
9.4.2.2 Take 5.00mL of sample solution B (5.2), place it in a 100mL volumetric flask, dilute to the mark with water, and shake. Determine the emission intensity of the potassium spectrum under the same conditions as the standard series solution II, and find the corresponding mass of potassium oxide from the working curve II according to the indicated value of the measured solution.
9.5 Expression of analysis results
The mass percentage of potassium sulfate (X,%) is calculated according to formula (4): X
m, × 10 ~3 × 1. 850
HG/T2516-93
Where: m—the mass of potassium oxide found from the working curve, mg; m
-the mass of the sample taken, g;
1.850 is the coefficient for converting the mass of potassium oxide into the mass of potassium sulfate. 9.6 Allowable error
The absolute difference between two parallel determination results shall not exceed 0.3%. 10 Determination of sodium sulfate content by flame photometry 10.1 Method summary
The sodium in the sample solution is determined by flame photometry and the working curve method is used for quantification. A large amount of potassium will affect the determination of a small amount of sodium, causing the result to be biased high, which can be eliminated by adding excess potassium salt. 10.2 Reagents and solutions
10.2.1 Hydrochloric acid (GB/T622) solution: 1+1.10.2.2 Ammonia water (GB/T631) solution: 1+3.10.2.3 Potassium chloride (GB/T646, premium grade) solution: 80g/L, stored in a polyethylene bottle, 10.2.4 Sodium oxide standard solution (1mL solution contains 1.00mgNaz0) Weigh 1.886 sodium chloride (GB/T1266, high-grade purity) burned to constant weight at 500-600℃, dissolve in water, transfer to a 1000mL volumetric flask, dilute to scale with water, shake well, and place in a polyethylene bottle. 10.2.5 Methyl orange indicator solution: 1g/L, prepared according to GB/T603. 10.3 Instrument
Flame photometer.
10.4 Analysis steps
10.4.1 Drawing of working curve
Add 0, 0.50, 1.00, 2.00, 3.00, 4.00 mL of sodium oxide standard solution (10.2.4) to 6 100 mL volumetric flasks respectively, which is equivalent to 0, 0.50, 1.00, 2.00, 3.00, 4.00 mg of sodium oxide. Add 4.0 mL of potassium chloride solution and 1.0 mL of hydrochloric acid solution (10.2.1) to each flask. Dilute to the scale with water and shake well. Using water as the reference, measure the emission intensity values of the sodium spectral lines of the standard series of solutions on a flame photometer. Use the obtained indication value as the ordinate and the corresponding mass of sodium oxide as the abscissa to draw the working curve. 10.4.2 Determination
Pipette 5.00mL of sample solution A (5.1) or sample solution B (5.2) into a 100mL volumetric flask, add 1 drop of methyl orange indicator solution, add ammonia solution (10.2.2) to neutralize until the solution turns yellow, add 1.0mL of hydrochloric acid solution (10.2.1), dilute to the scale with water, and shake well. Determine the emission intensity value of the sodium spectrum line under the same conditions as the standard series solutions, and find the corresponding mass of sodium oxide from the working curve according to the indicated value of the solution being tested. 10.5 Expression of analysis results
The mass percentage of sodium sulfate (X,%) is calculated according to formula (5): X
m,×10-×2. 292
Wherein: m,—the mass of sodium oxide found from the working curve, mg; m-the mass of the sample taken, g;
2.292-—the coefficient for converting the mass of sodium oxide into the mass of sodium sulfate. 10.6 Allowable difference
The absolute difference between the results of two parallel determinations shall not exceed 0.3%. 6
HG/T2516-93
11 Determination of phosphorus pentoxide content Phosphorus-vanadium-molybdenum yellow photometric method 11.1 Summary of the method
In nitric acid medium, the molybdenum-vanadium reagent reacts with phosphate to form a phosphorus-molybdenum-vanadium yellow complex, and its absorbance is measured at a wavelength of 440nm using a spectrophotometer.
11.2 Reagents and solutions
11.2.1 Nitric acid (GB/T626).
11.2.2 Citric acid (GB/T9855) solution: 100g/L. 11.2.3 Phosphorus pentoxide standard solution (1mL solution contains 0.200mgP,0,) Weigh 0.3835g potassium dihydrogen phosphate (GB/T1274), dissolve in water, transfer to a 1000mL volumetric flask, dilute with water to the mark, and shake well.
11.2.4 Molybdenum vanadium reagent
Prepare as follows:
a. Weigh 50g ammonium tantalum ((NH)Mo,O24.4H,O, GB/T657), accurate to 0.01g, dissolve in 500mL water, heat to 50-60℃, cool, filter, and obtain solution a. b. Weigh 1.5g ammonium metabisulfate (HG/T3-941) to an accuracy of 0.01g, dissolve in 250mL water, heat to 50-60℃, (if vanadate is yellow when dissolved, add a few drops of ammonia water before heating) filter the solution and cool. Add 250mL nitric acid (GB/T626) solution (1+3) to obtain solution b. c. While stirring, inject solution a into solution b, then add 350mL nitric acid (GB/T626), stir thoroughly, and store in a brown bottle. This solution can be stored for a long time. 11.3 Instrument
Spectrophotometer.
11.4 Analysis steps
11.4.1 Drawing of working curve
Add 0, 1.00, 2.00, 3.00, 4.00, and 5.00 mL of phosphorus pentoxide standard solution to 6 50 mL volumetric flasks respectively, which is equivalent to 0, 0.200, 0.400, 0.600, 0.800, and 1.00 mg of phosphorus pentoxide. Add water to about 30 mL (when measuring S109 type sample, add 0.50 mL of citric acid). Then add 10.0 mL of aluminum vanadium reagent, dilute with water to the scale, shake well, and let it stand for 20~30 min.
On a spectrophotometer, at a wavelength of 440 nm, use a 2 cm absorption cell and take the reagent blank solution as reference to measure the absorbance of the standard colorimetric solution.
Use the mass of phosphorus pentoxide as the abscissa and the corresponding absorbance value as the ordinate to draw a working curve. 11.4.2 Determination
When determining the content of phosphorus pentoxide in S108 vanadium catalyst, transfer 2.00~5.00mL of sample solution A (5.1) and place it in a 50mL volumetric flask, add water to about 39mL, add 10.0mL of vanadium reagent, dilute to the mark with water, and place it for 20~30min;
When determining the content of phosphorus pentoxide in S109 vanadium catalyst, transfer the filtrate D obtained by the determination of silicon dioxide content in Article 14.4 to a 250mL volumetric flask, dilute to the mark with water, shake the hook, transfer 20.00mL, place it in a 100mL beaker, add 3~4mL of nitric acid, heat on a sand bath to evaporate until almost dry, add nitric acid again, and repeat this 2~3 times. Remove and cool slightly, transfer the test solution into a 50mL volumetric flask with about 30mL of water, add 0.50mL of citric acid, 10.0mL of molybdenum vanadium reagent, dilute to the mark with water, shake well, and place for 20~30min
On a spectrophotometer, at a wavelength of 440nm, use a 2cm absorption cell, and use the reagent blank solution as a reference to measure the absorbance of the color solution being tested.
According to the absorbance value of the color solution being tested, the corresponding mass of phosphorus pentoxide can be found from the working curve. 7
11.5 Expression of analysis results
HG/T2516-93
The mass percentage (X.%) of phosphorus pentoxide is calculated according to formula (6): x.
In the formula: m,—mass of phosphorus pentoxide obtained from the working curve, mg; m——mass of the sample taken, g.
11.6 Allowable difference
The absolute difference between the results of two parallel measurements shall not exceed 0.07%. 12 Determination of antimony trioxide content Potassium iodide photometric method 12.1 Method summary
Antimony trivalent and iodide ions form a yellow SbI complex in an acidic solution. Its absorbance is measured by a spectrophotometer at a wavelength of 425nm.
12.2 Reagents and solutions
12.2.1 Sulfuric acid (GB/T 625).
12.2.2 Sulfuric acid (GB/T625) solution: 1+1. 12.2.3 Sulfuric acid (GB/T625) solution: 1+3. 12.2.4 Potassium iodide-thiourea solution
Weigh 225g potassium iodide (GB/T1272) and dissolve it in water, dilute to 500mL; weigh 50g thiourea (HG3-979) and dissolve it in hot water, cool, and dilute to 500mL. Mix the above two liquids and store them in a brown bottle. 12.2.5 Antimony trioxide standard solution (1 mL of solution contains 0.200 mg Sb20 g) Weigh 0.1670 g of metal antimony powder (purity 99.5% or more) and put it in a 250 mL beaker, add 50 mL of sulfuric acid (12.2.1), cover with blood, heat to dissolve, cool, dilute with 200 mL of sulfuric acid (12.2.3), transfer to a 1000 mL volumetric flask, cool to room temperature, dilute with water to the mark, and shake well.
12.3 Instrument
Spectrophotometer.
12.4 Analysis steps
12.4.1 Drawing of working curve
Add 0, 1.00, 2.00, 3.00, 4.00, 5.00, 6.00 mL of antimony trioxide standard solution to 7 50 mL volumetric flasks respectively, which is equivalent to 0, 0.200, 0.400, 0.600, 0.800, 1.00, 1.20 mL of antimony trioxide. Add 7.0, 6.8, 6.6, 6.4, 6, 2, 6.0, 5.8 mL of sulfuric acid solution (12.2.2) to each flask in turn, add water to about 20 mL, and cool to room temperature. Add 20.0 mL of potassium iodide-sulfur solution, shake well, dilute to the mark with water, and shake well. On a spectrophotometer, at a wavelength of 425 nm, use a 1 cm absorption cell and the reagent blank solution as a reference to measure the absorbance of the standard colorimetric solution.
Use the mass of antimony trioxide as the abscissa and the corresponding absorbance value as the ordinate to draw a working curve. 12.4.2 Determination
Pipette 5.00 mL of sample solution B (5.2) into a 50 mL volumetric flask, add 6.0 mL of sulfuric acid (12.2.2), (when the antimony trioxide content is greater than 2%, pipette 2.00mL sample solution B, add 6.6mL sulfuric acid (12.2.2)) and water to about 20mL, cool to room temperature. Add 20.0mL potassium iodide-thiourea solution, shake well, dilute to scale with water, and shake for 3 minutes. Measure the absorbance of the color solution under the same conditions as the standard color solution. According to the absorbance value of the color solution, the corresponding mass of antimony trioxide can be found from the working curve. 12.5 Expression of analysis results
HG/T2516—93
The mass percentage of antimony trioxide (X, %) is calculated according to formula (7): X,
m,×10~3
Wherein: m,——mass of antimony trioxide obtained from the working curve, mg; mass of the sample taken, g.
12.6 Allowable difference
The absolute difference between the results of two parallel determinations shall not exceed 0.07%. 13 Determination of ferric oxide content Sulfosalicylic acid photometric method 13.1 Summary of the method
In an ammonia solution with a pH of 8-11, sulfosalicylic acid and blue-valent iron form a stable yellow complex, and its absorbance is measured at a wavelength of 420nm by a spectrophotometer.
13.2 Reagents and solutions
13.2.1 Sulfosalicylic acid (GB/T10705) solution: 200g/L. 13.2.2 Ammonia (GB/T631) solution: 1+1. 13.2.3 Hydrochloric acid (GB/T622) solution: 1+1. 13.2.4 Ferric oxide standard solution (1mL solution contains 1.00mgFe,0,) Weigh 1.000g of ferric oxide (purity above 99.5%) burned at 900℃ to constant weight, add 20mL of hydrochloric acid solution (13.2.3) to a 250mL beaker, heat at low temperature to dissolve, cool, transfer to a 1000mL volumetric flask, dilute to scale with water, and shake well.
13.2.5 Ferric oxide standard solution (1 mL solution contains 0.100 mgFe,0,) Pipette 10.00 mL of ferric oxide standard solution (13.2.4) into a 100 mL volumetric flask, dilute to the mark with water, and shake well.
13.3 Instruments
Spectrophotometer.
13.4 Analysis steps
13.4.1 Preparation of working curve
Add 0, 1.00, 2.00, 3.00, 4.00, 5.00 mL of ferric oxide standard solution (13.2.5) to 6 50 mL volumetric flasks respectively, which is equivalent to 0, 0.100, 0.300, 0.400, 0.500 mg of ferric oxide, add water to about 10 mL, add 5.0 mL of sulfosalicylic acid solution, neutralize with ammonia solution (13.2.2) until the solution turns yellow and add 2.0 mL in excess (add 2.0 mL after neutralizing the solution in the first volumetric flask to alkalinity). Dilute with water to the scale, shake well, and let stand for 10 minutes. On a spectrophotometer, at a wavelength of 420 nm, use a 1 cm absorption cell and use the reagent blank solution as a reference to measure the absorbance of the standard colorimetric solution.
Use the mass of ferric oxide as the horizontal axis and the corresponding absorbance value as the vertical axis to draw a working curve. 13.4.2 Determination
Pipette 2.00~5.00mL of sample solution A (5.1) or sample solution B (5.2) into a 50mL volumetric flask, add water to about 10mL, add 5.0mL of sulfosalicylic acid solution, neutralize with ammonia solution (13.2.2) until the solution turns yellow and has an excess of 2.0mL, dilute with water to the scale, shake the spoon, and let it stand for 10min. Under the same conditions as the standard color solution, measure the absorbance of the color solution to be tested. According to the absorbance value of the color solution to be tested, find the corresponding mass of ferric oxide from the working curve. 13.5 Expression of analysis results
The mass percentage of ferric oxide (X.%) is calculated according to formula (8): X
HG/T2516-93
m,×10-3
Wherein: m--the mass of ferric oxide found on the working curve, mg; the mass of the sample taken in one part, nominal.bZxz.net
13.6 Allowable difference
The absolute difference between the results of two parallel determinations shall not exceed 0.05%. 14 Determination of silicon dioxide content by weighing method
14.1 Summary of the method
The sample is melted and decomposed with sodium hydroxide, extracted with hot water, acidified, and then heated and evaporated to near dryness. Animal gel is added to condense soluble silicon. After filtering, burning, cooling, weighing, the silicon dioxide content is calculated. 14.2 Reagents and solutions
14.2.1 Sodium hydroxide (GB/T629).
14.2.2 Hydrochloric acid (GB/T622).
14.2.3 Hydrochloric acid (GB/T622) solution: 1+50. 14.2.4 Animal glue solution: 10g/L
1.0g animal glue is dissolved in 100mL 60~70℃ water and prepared when needed. 14.3 Analysis steps
Weigh about 0.5g of the sample, accurate to 0.0001g, and place it in a nickel-glycidyl sulfate solution containing 4g of sodium hydroxide. Cover it, move it into a high-temperature furnace, gradually heat it to 500℃, melt it for 10min, take it out, cool it, rinse the outer wall of the crucible with water, put it into a polytetrafluoroethylene plastic cup, add 70~80mL of hot water, cover it with a lid, heat it to completely leach the frit, rinse the crucible with water and take it out: slowly add 25mL of hydrochloric acid (14.2.2) into the test solution, stir it evenly, and transfer the test solution completely to a 250~400mL glass crucible. Place a glass tripod in the cup, cover with a watch glass, place on a sand bath and evaporate at low temperature until almost dry, so that it is in the form of wet salt, add 25mL of hydrochloric acid (14.2.2), stir and heat to 80℃, add 8mL of animal glue solution, stir thoroughly and keep warm at 70~80℃ for about 10min, rinse the beaker wall with hot water, and dilute to about 80mL, stir to dissolve the salt, filter with rapid quantitative filter paper, wash the beaker and precipitate 3~4 times with hot hydrochloric acid (14.2.3), wipe the beaker with a small piece of quantitative filter paper and filter into the precipitate, and then wash the precipitate with hot water 8~10 times. The retained filtrate D of the S109 type sample is used for the determination of phosphorus pentoxide content. Transfer the precipitate and the filter paper to a porcelain crucible burned to constant weight at 900℃, first place it on an electric furnace for ashing, then move it to a high-temperature furnace, burn at 900~950℃ for 1h, take it out, place it in a desiccator to cool to room temperature, weigh it, and burn it to constant weight. 14.4 Expression of analysis results
The mass percentage of silicon dioxide (X.%) is calculated according to formula (9): X,
precipitate and crucible mass, g
where: m2
mi—crub mass, g;
—sample mass, g.
14.5 Allowable difference
The absolute difference between two parallel determination results shall not exceed 0.6%. 10
HG/T2516--93
Additional remarks:
This standard was proposed by the Science and Technology Department of the Ministry of Chemical Industry of the People's Republic of China and is under the jurisdiction of the Research Institute of Nanjing Chemical Industry (Group) Corporation. This standard was drafted by the Research Institute of Nanjing Chemical Industry (Group) Corporation. The main drafters of this standard are Jia Zhuru and Zhu Shuyuan. 115 Ferric oxide standard solution (1 mL solution contains 0.100 mg Fe,0,) Pipette 10.00 mL of ferric oxide standard solution (13.2.4) into a 100 mL volumetric flask, dilute to scale with water, and shake well.
13.3 Instruments
Spectrophotometer.
13.4 Analysis steps
13.4.1 Preparation of working curve
Add 0, 1.00, 2.00, 3.00, 4.00, 5.00mL of ferric oxide standard solution (13.2.5) to 6 50mL volumetric flasks respectively, which is equivalent to 0, 0.100, 0.300, 0.400, 0.500mg of ferric oxide, add water to about 10mL, add 5.0mL of sulfosalicylic acid solution, neutralize with ammonia solution (13.2.2) until the solution turns yellow and add 2.0mL in excess (add 2.0mL after neutralizing the solution in the first volumetric flask to alkalinity). Dilute with water to the scale, shake well, and let stand for 10min. On a spectrophotometer, at a wavelength of 420nm, use a 1cm absorption cell and use the reagent blank solution as a reference to measure the absorbance of the standard colorimetric solution.
Use the mass of ferric oxide as the horizontal axis and the corresponding absorbance value as the vertical axis to draw a working curve. 13.4.2 Determination
Pipette 2.00~5.00mL of sample solution A (5.1) or sample solution B (5.2) into a 50mL volumetric flask, add water to about 10mL, add 5.0mL of sulfosalicylic acid solution, neutralize with ammonia solution (13.2.2) until the solution turns yellow and has an excess of 2.0mL, dilute with water to the scale, shake the spoon, and let it stand for 10min. Under the same conditions as the standard color solution, measure the absorbance of the color solution to be tested. According to the absorbance value of the color solution to be tested, find the corresponding mass of ferric oxide from the working curve. 13.5 Expression of analysis results
The mass percentage of ferric oxide (X.%) is calculated according to formula (8): X
HG/T2516-93
m,×10-3
Wherein: m--the mass of ferric oxide found on the working curve, mg; the mass of the sample taken in one part, nominal.
13.6 Allowable difference
The absolute difference between the results of two parallel determinations shall not exceed 0.05%. 14 Determination of silicon dioxide content by weighing method
14.1 Summary of the method
The sample is melted and decomposed with sodium hydroxide, extracted with hot water, acidified, and then heated and evaporated to near dryness. Animal gel is added to condense soluble silicon. After filtering, burning, cooling, weighing, the silicon dioxide content is calculated. 14.2 Reagents and solutions
14.2.1 Sodium hydroxide (GB/T629).
14.2.2 Hydrochloric acid (GB/T622).
14.2.3 Hydrochloric acid (GB/T622) solution: 1+50. 14.2.4 Animal glue solution: 10g/L
1.0g animal glue is dissolved in 100mL 60~70℃ water and prepared when needed. 14.3 Analysis steps
Weigh about 0.5g of the sample, accurate to 0.0001g, and place it in a nickel-glycidyl sulfate solution containing 4g of sodium hydroxide. Cover it, move it into a high-temperature furnace, gradually heat it to 500℃, melt it for 10min, take it out, cool it, rinse the outer wall of the crucible with water, put it into a polytetrafluoroethylene plastic cup, add 70~80mL of hot water, cover it with a lid, heat it to completely leach the frit, rinse the crucible with water and take it out: slowly add 25mL of hydrochloric acid (14.2.2) into the test solution, stir it evenly, and transfer the test solution completely to a 250~400mL glass crucible. Place a glass tripod in the cup, cover with a watch glass, place on a sand bath and evaporate at low temperature until almost dry, so that it is in the form of wet salt, add 25mL of hydrochloric acid (14.2.2), stir and heat to 80℃, add 8mL of animal glue solution, stir thoroughly and keep warm at 70~80℃ for about 10min, rinse the beaker wall with hot water, and dilute to about 80mL, stir to dissolve the salt, filter with rapid quantitative filter paper, wash the beaker and precipitate 3~4 times with hot hydrochloric acid (14.2.3), wipe the beaker with a small piece of quantitative filter paper and filter into the precipitate, and then wash the precipitate with hot water 8~10 times. The retained filtrate D of the S109 type sample is used for the determination of phosphorus pentoxide content. Transfer the precipitate and the filter paper to a porcelain crucible burned to constant weight at 900℃, first place it on an electric furnace for ashing, then move it to a high-temperature furnace, burn at 900~950℃ for 1h, take it out, place it in a desiccator to cool to room temperature, weigh it, and burn it to constant weight. 14.4 Expression of analysis results
The mass percentage of silicon dioxide (X.%) is calculated according to formula (9): X,
precipitate and crucible mass, g
where: m2
mi—crub mass, g;
—sample mass, g.
14.5 Allowable difference
The absolute difference between two parallel determination results shall not exceed 0.6%. 10
HG/T2516--93
Additional remarks:
This standard was proposed by the Science and Technology Department of the Ministry of Chemical Industry of the People's Republic of China and is under the jurisdiction of the Research Institute of Nanjing Chemical Industry (Group) Corporation. This standard was drafted by the Research Institute of Nanjing Chemical Industry (Group) Corporation. The main drafters of this standard are Jia Zhuru and Zhu Shuyuan. 115 Ferric oxide standard solution (1 mL solution contains 0.100 mg Fe,0,) Pipette 10.00 mL of ferric oxide standard solution (13.2.4) into a 100 mL volumetric flask, dilute to scale with water, and shake well.
13.3 Instruments
Spectrophotometer.
13.4 Analysis steps
13.4.1 Preparation of working curve
Add 0, 1.00, 2.00, 3.00, 4.00, 5.00mL of ferric oxide standard solution (13.2.5) to 6 50mL volumetric flasks respectively, which is equivalent to 0, 0.100, 0.300, 0.400, 0.500mg of ferric oxide, add water to about 10mL, add 5.0mL of sulfosalicylic acid solution, neutralize with ammonia solution (13.2.2) until the solution turns yellow and add 2.0mL in excess (add 2.0mL after neutralizing the solution in the first volumetric flask to alkalinity). Dilute with water to the scale, shake well, and let stand for 10min. On a spectrophotometer, at a wavelength of 420nm, use a 1cm absorption cell and use the reagent blank solution as a reference to measure the absorbance of the standard colorimetric solution.
Use the mass of ferric oxide as the horizontal axis and the corresponding absorbance value as the vertical axis to draw a working curve. 13.4.2 Determination
Pipette 2.00~5.00mL of sample solution A (5.1) or sample solution B (5.2) into a 50mL volumetric flask, add water to about 10mL, add 5.0mL of sulfosalicylic acid solution, neutralize with ammonia solution (13.2.2) until the solution turns yellow and has an excess of 2.0mL, dilute with water to the scale, shake the spoon, and let it stand for 10min. Under the same conditions as the standard color solution, measure the absorbance of the color solution to be tested. According to the absorbance value of the color solution to be tested, find the corresponding mass of ferric oxide from the working curve. 13.5 Expression of analysis results
The mass percentage of ferric oxide (X.%) is calculated according to formula (8): X
HG/T2516-93
m,×10-3
Wherein: m--the mass of ferric oxide found on the working curve, mg; the mass of the sample taken in one part, nominal.
13.6 Allowable difference
The absolute difference between the results of two parallel determinations shall not exceed 0.05%. 14 Determination of silicon dioxide content by weighing method
14.1 Summary of the method
The sample is melted and decomposed with sodium hydroxide, extracted with hot water, acidified, and then heated and evaporated to near dryness. Animal gel is added to condense soluble silicon. After filtering, burning, cooling, weighing, the silicon dioxide content is calculated. 14.2 Reagents and solutions
14.2.1 Sodium hydroxide (GB/T629).
14.2.2 Hydrochloric acid (GB/T622).
14.2.3 Hydrochloric acid (GB/T622) solution: 1+50. 14.2.4 Animal glue solution: 10g/L
1.0g animal glue is dissolved in 100mL 60~70℃ water and prepared when needed. 14.3 Analysis steps
Weigh about 0.5g of the sample, accurate to 0.0001g, and place it in a nickel-glycidyl sulfate solution containing 4g of sodium hydroxide. Cover it, move it into a high-temperature furnace, gradually heat it to 500℃, melt it for 10min, take it out, cool it, rinse the outer wall of the crucible with water, put it into a polytetrafluoroethylene plastic cup, add 70~80mL of hot water, cover it with a lid, heat it to completely leach the frit, rinse the crucible with water and take it out: slowly add 25mL of hydrochloric acid (14.2.2) into the test solution, stir it evenly, and transfer the test solution completely to a 250~400mL glass crucible. Place a glass tripod in the cup, cover with a watch glass, place on a sand bath and evaporate at low temperature until almost dry, so that it is in the form of wet salt, add 25mL of hydrochloric acid (14.2.2), stir and heat to 80℃, add 8mL of animal glue solution, stir thoroughly and keep warm at 70~80℃ for about 10min, rinse the beaker wall with hot water, and dilute to about 80mL, stir to dissolve the salt, filter with rapid quantitative filter paper, wash the beaker and precipitate 3~4 times with hot hydrochloric acid (14.2.3), wipe the beaker with a small piece of quantitative filter paper and filter into the precipitate, and then wash the precipitate with hot water 8~10 times. The retained filtrate D of the S109 type sample is used for the determination of phosphorus pentoxide content. Transfer the precipitate and the filter paper to a porcelain crucible burned to constant weight at 900℃, first place it on an electric furnace for ashing, then move it to a high-temperature furnace, burn at 900~950℃ for 1h, take it out, place it in a desiccator to cool to room temperature, weigh it, and burn it to constant weight. 14.4 Expression of analysis results
The mass percentage of silicon dioxide (X.%) is calculated according to formula (9): X,
precipitate and crucible mass, g
where: m2
mi—crub mass, g;
—sample mass, g.
14.5 Allowable difference
The absolute difference between two parallel determination results shall not exceed 0.6%. 10
HG/T2516--93
Additional remarks:
This standard was proposed by the Science and Technology Department of the Ministry of Chemical Industry of the People's Republic of China and is under the jurisdiction of the Research Institute of Nanjing Chemical Industry (Group) Corporation. This standard was drafted by the Research Institute of Nanjing Chemical Industry (Group) Corporation. The main drafters of this standard are Jia Zhuru and Zhu Shuyuan. 112), stir and heat to 80℃, add 8mL of animal glue solution, stir thoroughly and keep warm at 70~80℃ for about 10min, rinse the beaker wall with hot water, dilute to about 80mL, stir to dissolve the salt, filter with fast quantitative filter paper, wash the beaker and precipitate 3~4 times with hot hydrochloric acid (14.2.3), wipe the beaker with a small piece of quantitative filter paper and filter into the precipitate, and then wash the precipitate with hot water 8~10 times. The retained filtrate D of the S109 type sample is used for the determination of phosphorus pentoxide content. The precipitate and the filter paper are transferred to a porcelain crucible burned to constant weight at 900℃, first placed on an electric furnace for incineration, and then transferred to a high-temperature furnace, burned at 900~950℃ for 1h, taken out, placed in a desiccator to cool to room temperature, weighed, and burned to constant weight. 14.4 Expression of analysis results
The mass percentage of silicon dioxide (X.%) is calculated according to formula (9): X,
precipitate and crucible mass, g
where: m2
mi—crub mass, g;
—sample mass, g.
14.5 Allowable difference
The absolute difference between two parallel determination results shall not exceed 0.6%. 10
HG/T2516--93
Additional remarks:
This standard was proposed by the Science and Technology Department of the Ministry of Chemical Industry of the People's Republic of China and is under the jurisdiction of the Research Institute of Nanjing Chemical Industry (Group) Corporation. This standard was drafted by the Research Institute of Nanjing Chemical Industry (Group) Corporation. The main drafters of this standard are Jia Zhuru and Zhu Shuyuan. 112), stir and heat to 80℃, add 8mL of animal glue solution, stir thoroughly and keep warm at 70~80℃ for about 10min, rinse the beaker wall with hot water, dilute to about 80mL, stir to dissolve the salt, filter with fast quantitative filter paper, wash the beaker and precipitate 3~4 times with hot hydrochloric acid (14.2.3), wipe the beaker with a small piece of quantitative filter paper and filter into the precipitate, and then wash the precipitate with hot water 8~10 times. The retained filtrate D of the S109 type sample is used for the determination of phosphorus pentoxide content. The precipitate and the filter paper are transferred to a porcelain crucible burned to constant weight at 900℃, first placed on an electric furnace for incineration, and then transferred to a high-temperature furnace, burned at 900~950℃ for 1h, taken out, placed in a desiccator to cool to room temperature, weighed, and burned to constant weight. 14.4 Expression of analysis results
The mass percentage of silicon dioxide (X.%) is calculated according to formula (9): X,
precipitate and crucible mass, g
where: m2
mi—crub mass, g;
—sample mass, g.
14.5 Allowable difference
The absolute difference between two parallel determination results shall not exceed 0.6%. 10
HG/T2516--93
Additional remarks:
This standard was proposed by the Science and Technology Department of the Ministry of Chemical Industry of the People's Republic of China and is under the jurisdiction of the Research Institute of Nanjing Chemical Industry (Group) Corporation. This standard was drafted by the Research Institute of Nanjing Chemical Industry (Group) Corporation. The main drafters of this standard are Jia Zhuru and Zhu Shuyuan. 11
Tip: This standard content only shows part of the intercepted content of the complete standard. If you need the complete standard, please go to the top to download the complete standard document for free.