CN101173916A - Method for eliminating error in vanadium determination by ammonium ferrous sulfate volumetric method - Google Patents
Method for eliminating error in vanadium determination by ammonium ferrous sulfate volumetric method Download PDFInfo
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- CN101173916A CN101173916A CNA2007102028158A CN200710202815A CN101173916A CN 101173916 A CN101173916 A CN 101173916A CN A2007102028158 A CNA2007102028158 A CN A2007102028158A CN 200710202815 A CN200710202815 A CN 200710202815A CN 101173916 A CN101173916 A CN 101173916A
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- vanadium
- ammonium sulfate
- titration
- solution
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- 229910052720 vanadium Inorganic materials 0.000 title claims abstract description 60
- LEONUFNNVUYDNQ-UHFFFAOYSA-N vanadium atom Chemical compound [V] LEONUFNNVUYDNQ-UHFFFAOYSA-N 0.000 title claims abstract description 60
- IMBKASBLAKCLEM-UHFFFAOYSA-L ferrous ammonium sulfate (anhydrous) Chemical compound [NH4+].[NH4+].[Fe+2].[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O IMBKASBLAKCLEM-UHFFFAOYSA-L 0.000 title claims abstract description 21
- 238000000034 method Methods 0.000 title abstract description 19
- 229940010514 ammonium ferrous sulfate Drugs 0.000 title description 2
- 238000004448 titration Methods 0.000 claims abstract description 28
- LPXPTNMVRIOKMN-UHFFFAOYSA-M sodium nitrite Chemical compound [Na+].[O-]N=O LPXPTNMVRIOKMN-UHFFFAOYSA-M 0.000 claims abstract description 26
- 239000000243 solution Substances 0.000 claims abstract description 18
- 239000012086 standard solution Substances 0.000 claims abstract description 17
- 235000010288 sodium nitrite Nutrition 0.000 claims abstract description 13
- XSQUKJJJFZCRTK-UHFFFAOYSA-N Urea Chemical compound NC(N)=O XSQUKJJJFZCRTK-UHFFFAOYSA-N 0.000 claims abstract description 12
- 239000004202 carbamide Substances 0.000 claims abstract description 12
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 claims abstract description 8
- 229910052804 chromium Inorganic materials 0.000 claims abstract description 8
- 239000011651 chromium Substances 0.000 claims abstract description 8
- ZLXPLDLEBORRPT-UHFFFAOYSA-M [NH4+].[Fe+].[O-]S([O-])(=O)=O Chemical compound [NH4+].[Fe+].[O-]S([O-])(=O)=O ZLXPLDLEBORRPT-UHFFFAOYSA-M 0.000 claims description 15
- 239000007788 liquid Substances 0.000 claims description 13
- NUJOXMJBOLGQSY-UHFFFAOYSA-N manganese dioxide Chemical compound O=[Mn]=O NUJOXMJBOLGQSY-UHFFFAOYSA-N 0.000 claims description 12
- 239000002244 precipitate Substances 0.000 claims description 7
- 238000012546 transfer Methods 0.000 claims description 5
- 238000004519 manufacturing process Methods 0.000 abstract description 5
- 239000012286 potassium permanganate Substances 0.000 abstract description 5
- 230000002829 reductive effect Effects 0.000 abstract description 5
- ZWJINEZUASEZBH-UHFFFAOYSA-N fenamic acid Chemical compound OC(=O)C1=CC=CC=C1NC1=CC=CC=C1 ZWJINEZUASEZBH-UHFFFAOYSA-N 0.000 abstract description 4
- 238000011160 research Methods 0.000 abstract description 3
- 238000004458 analytical method Methods 0.000 abstract 1
- 230000001590 oxidative effect Effects 0.000 abstract 1
- 238000005259 measurement Methods 0.000 description 9
- 239000002893 slag Substances 0.000 description 8
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 6
- GNTDGMZSJNCJKK-UHFFFAOYSA-N divanadium pentaoxide Chemical compound O=[V](=O)O[V](=O)=O GNTDGMZSJNCJKK-UHFFFAOYSA-N 0.000 description 4
- PNXOJQQRXBVKEX-UHFFFAOYSA-N iron vanadium Chemical compound [V].[Fe] PNXOJQQRXBVKEX-UHFFFAOYSA-N 0.000 description 4
- 229910052742 iron Inorganic materials 0.000 description 3
- 230000005477 standard model Effects 0.000 description 3
- 238000012360 testing method Methods 0.000 description 3
- 230000004308 accommodation Effects 0.000 description 2
- 229910045601 alloy Inorganic materials 0.000 description 2
- 239000000956 alloy Substances 0.000 description 2
- 238000013459 approach Methods 0.000 description 2
- 238000003556 assay Methods 0.000 description 2
- 239000003795 chemical substances by application Substances 0.000 description 2
- KQFUCKFHODLIAZ-UHFFFAOYSA-N manganese Chemical compound [Mn].[Mn] KQFUCKFHODLIAZ-UHFFFAOYSA-N 0.000 description 2
- 238000007254 oxidation reaction Methods 0.000 description 2
- 239000008188 pellet Substances 0.000 description 2
- KMUONIBRACKNSN-UHFFFAOYSA-N potassium dichromate Chemical compound [K+].[K+].[O-][Cr](=O)(=O)O[Cr]([O-])(=O)=O KMUONIBRACKNSN-UHFFFAOYSA-N 0.000 description 2
- 239000002994 raw material Substances 0.000 description 2
- 238000005245 sintering Methods 0.000 description 2
- 229910000831 Steel Inorganic materials 0.000 description 1
- SKKMWRVAJNPLFY-UHFFFAOYSA-N azanylidynevanadium Chemical compound [V]#N SKKMWRVAJNPLFY-UHFFFAOYSA-N 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 229910052593 corundum Inorganic materials 0.000 description 1
- 239000010431 corundum Substances 0.000 description 1
- 238000006477 desulfuration reaction Methods 0.000 description 1
- 230000023556 desulfurization Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- -1 electroslag Substances 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- 239000013067 intermediate product Substances 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000003918 potentiometric titration Methods 0.000 description 1
- 238000001556 precipitation Methods 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 239000000047 product Substances 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 238000010561 standard procedure Methods 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
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- Investigating Or Analyzing Non-Biological Materials By The Use Of Chemical Means (AREA)
Abstract
The invention relates to a method for remedying errors in vanadium determination by a ferrous ammonium sulfate volumetric method, which can effectively remedy the titration errors caused by factors such as mismatching of the concentration of a selected ferrous ammonium sulfate titration solution and the content of vanadium in a sample, inaccurate titration end point judgment and the like in the vanadium constant analysis operation. Specifically, potassium permanganate is used for oxidizing vanadium in the over-titrated or not-yet-reached solution to be detected into V5+And the chromium is not oxidized, the excessive potassium permanganate is reduced by using sodium nitrite in the presence of urea, and the excessive sodium nitrite can be decomposed by the presence of urea, so that the interference of the excessive sodium nitrite on titration is eliminated. And then taking N-phenyl anthranilic acid as an indicator, and titrating the vanadium by using the ferrous ammonium sulfate standard solution again. The method is suitable for measuring vanadium in a sample with the total vanadium content of more than 1.00 percent and the chromium content of less than 1.00 percent, and compared with the existing national standard, the method has the advantages of enlarging the measuring range, reducing the rework rate in operation and better serving scientific research and production.
Description
Technical field
The present invention relates to the method for volumetric determination content of vanadium, particularly a kind of method of slipping up when eliminating the volumetric determination content of vanadium.
Background technology
At present, the assay method of content of vanadium generally adopts ammonium ferrous sulfate volumetric method in the samples such as iron ore, sintering deposit, pellet, vanadium slag, vanadium pentoxide.But can only use the iron ammonium sulfate standard solution of fixed concentration to each particular sample in the existing GB, and can not be applied to the assay determination of vanadium in the not clear slag specimen in slag, electroslag, corundum slag, desulfurization slag and source or various raw material, the alloy.
In actual production, the sample to be tested component is very complicated usually, especially some scientific research task is according to raw material, intermediate product and the product of special requirement preparation, the content of vanadium is difficult to predict accurately in advance in which scope in the sample to be tested, thereby the iron ammonium sulfate standard solution that is difficult to accurately to choose suitable concn carries out redox titration.Thereby in titration process, very easily causing titration end-point excessive, the l ferrous ammonium sulfate solution concentration of selection and content of vanadium do not match and cause the excessive also no show terminal point of standard solution consumption, or the titration error that causes because of titration end-point error in judgement, buret spill and leakage etc.Above-mentioned these errors happen occasionally in the practical measurement of production testing, cause regular doing over again, and have wasted lot of manpower and material resources.
Therefore, according to existing standard method (GB6730.32-86: vanadium quantitative determination in iron ore, sintering deposit, the pellet; GB223.13-89: vanadium quantitative determination in iron and steel and the alloy; GB7315.1-87: vanadium quantitative determination in the vanadium pentoxide; YB/T547.1-1995: the mensuration of vanadium in the vanadium slag) content of vanadium in the test samples, can not well satisfy demand of practical production.This area need be studied the analytical approach of measuring vanadium by ferrous ammonium sulfate capacitance at present, and invention can make this analytical approach measurement range enlarge, and accommodation is wideer, and practicality is stronger, better the means to save the situation of a kind of excessive error of serving for research and production.
Summary of the invention
The purpose of this invention is to provide a kind of means to save the situation that is applied to error when measuring vanadium by ferrous ammonium sulfate capacitance, the measurement range of measuring vanadium by ferrous ammonium sulfate capacitance is enlarged, and reduce the rework rate in the practical operation.
The inventive method may further comprise the steps:
A, sample weighting amount be m gram contain vanadium liquid to be measured, when overtitration or also during the no show terminal point, add liquor potassic permanganate therein, when stable manganese dioxide precipitate occurs, placed 3～5 minutes;
Add urea in b, the solution after a step is placed, and transfer to manganese dioxide precipitate with sodium nitrite solution and disappear, excessive 1～2 is that the iron ammonium sulfate standard solution of CmoL/L carries out titration with concentration, writes down the volume VmL of institute's quota of expenditure solution;
C, V are exactly the volume that contains the iron ammonium sulfate standard solution of vanadium liquid consumption to be measured, and the content of vanadium is by formula
Calculate, wherein the molal weight of vanadium is 50.94g/moL.
Wherein, liquor potassic permanganate concentration is 15g/L～25g/L among the step a; Sodium nitrite solution concentration is 15g/L～25g/L among the step b, and the urea addition is 0.5～1g.The urea addition is mainly looked the fluctuation of sodium nitrite consumption and is regulated, and facts have proved, the urea addition is excessive in not influence of measurement result.
The cardinal principle of the inventive method is: when adopting measuring vanadium by ferrous ammonium sulfate capacitance, when misoperationes such as l ferrous ammonium sulfate solution concentration and content of vanadium that overtitration, selection occur do not match, buret spill and leakage, directly at normal temperatures vanadium in the liquid to be measured of titration error is oxidized to V with potassium permanganate
5+And chromium is not oxidized, with sodium nitrite excessive potassium permanganate is reduced in the presence of urea, and the sodium nitrite of the existence of urea energy decomposing excessive is eliminated the interference of excessive sodium nitrite to titration simultaneously.Be indicator with the N phenylanthranilic acid again, use iron ammonium sulfate standard solution titration vanadium again.
In addition, find by test: when the full content of vanadium of sample to be tested (mass percent) less than 1.00% the time, the concentration of selected iron ammonium sulfate standard solution can be lower, be about 0.01mol/L, the iron ammonium sulfate standard solution of low concentration and the reaction of the vanadium of low concentration are insensitive, adopt means to save the situation effect of the present invention bad; Working as chromium content in the sample greater than 1.00%, is to eliminate chromium the mensuration of vanadium is disturbed, and needs to add a certain amount of reductive agent to the chromium selective reduction before titration, owing to the enforcement that affiliation influences means to save the situation of the present invention that adds of this reductive agent.
Therefore, the main applicable scope of the present invention is: full content of vanadium greater than 1.00%, chromium content is less than the mensuration of vanadium in 1.00% the sample.
Beneficial effect of the present invention: effectively remedied the normal error that occurs in the measuring vanadium by ferrous ammonium sulfate capacitance operation, reduced rework rate, had easy and simple to handlely, be easy to grasp, accuracy height, adaptable characteristics; Enlarged the accommodation of measuring vanadium by ferrous ammonium sulfate capacitance, when the content of vanadium in the sample to be tested not in the GB scope, active overtitration that can be earlier artificial adopts method of the present invention to measure the content of vanadium in the sample again.
Embodiment
The invention will be further elaborated below in conjunction with embodiment.Embodiment only is used to illustrate the present invention, rather than limits the present invention by any way.
Embodiment 1 overtitration error means to save the situation
Carry out titration operation with two standard model vessel slags, respectively same sample is carried out twice parallel titration, gained the results are shown in Table 1, and standard value is a numerical value given on the vessel slag standard model.
Table 1
When liquid to be measured overtitration occurs, when selecting misoperation such as ferrous ammonium sulfate concentration and content of vanadium does not match, buret spill and leakage, with the liquor potassic permanganate of 20g/L liquid to be measured transferred to two stable manganese manganese and precipitate appearance, placed 3 minutes; Add 0.8 gram urea, transfer to manganese dioxide precipitate with the 20g/L sodium nitrite solution and disappear, excessive 1～2, placed 2 minutes; Being indicator with 2g/L N-phenylanthranilic acid again, is that the iron ammonium sulfate standard solution of 0.02moL/L carries out titration with concentration, writes down the volume V of institute's quota of expenditure solution
1V
1Be exactly the volume of the iron ammonium sulfate standard solution of original liquid consumption to be measured, can calculate the content of vanadium in the original liquid to be measured.That uses the means to save the situation titration the results are shown in Table 2.
Table 2
In the normal titration operation, V in sample
2O
5Content is at 2.0～5.0% o'clock, is ± 0.15% to the analytical error allowed band of vanadium.Therefore, by table 1,2 as can be seen: adopt potassium permanganate re-oxidation method to overtitration error to remedy measurement result identical, respond well with standard value, the accuracy height, precision is good, the measuring vanadium by ferrous ammonium sulfate capacitance method is played well additional and perfect.
Embodiment 2 exceeds the titration method of GB measurement range sample
GB (GS/T8704.5-94) method is to adopt potentiometric titration to the mensuration of vanadium amount in the vanadium iron; when vanadium in vanadium iron or the vanadium nitride is measured; if still adopt volumetric determination ferrous ammonium sulfate; be difficult to the concentration range that criterion solution should be chosen in advance; therefore can select error usually, not only time-consuming but also inaccurate.This situation takes following means to save the situation can guarantee result's accuracy.
Same vanadium iron standard specimen is carried out twice replicate determination, at first adopt the maximum concentration 0.05moL/L of iron ammonium sulfate standard solution in the GB, the quota of expenditure liquor capacity surpasses 70mL, and (the standard liquor capacity preferably is controlled at below the 70mL during volumetric method titration, change little with the acidity that guarantees solution to be measured, also be convenient to simultaneously operation), still do not arrive terminal point, at this moment just adopt potassium dichromate re-oxidation method to remedy, liquor potassic permanganate with 22g/L transfers to stable two manganese manganese precipitation appearance with liquid to be measured, places 4 minutes; Add 1 gram urea, transfer to manganese dioxide precipitate with the 22g/L sodium nitrite solution and disappear, excessive 1～2, placed 3 minutes; Be indicator with 2g/L N-phenylanthranilic acid again, carry out titration, write down the volume V of institute's quota of expenditure solution with the iron ammonium sulfate standard solution of 0.10moL/L
2V
2Be exactly the volume of the iron ammonium sulfate standard solution of original liquid consumption to be measured, can calculate the content of vanadium in the original liquid to be measured, gained the results are shown in Table 3.Standard value is a numerical value (choose the iron ammonium sulfate standard solution titration by GB, institute's quota of expenditure liquor capacity is big, can not get accurate measurement result) given on the vanadium iron standard model.
Table 3
As known from Table 3, the present invention can be to remedying mensuration greater than the sample of GB measurement range, coincide with standard value (when the content of vanadium in the sample≤85.00%, the error that allows is: ± 0.40%), replicate determination value favorable reproducibility, show the accuracy height that the present invention measures this sample that exceeds the GB measurement range, precision is good, and the scope of application is wider.
Claims (4)
1. the means to save the situation of titration error during a measuring vanadium by ferrous ammonium sulfate capacitance is characterized in that: may further comprise the steps:
A) sample weighting amount be m gram contain vanadium liquid to be measured, when overtitration or also during the no show terminal point, add liquor potassic permanganate therein, when stable manganese dioxide precipitate occurs, placed 3～5 minutes;
B) add urea in the solution after a step is placed, and transfer to manganese dioxide precipitate with sodium nitrite solution and disappear, excessive 1～2 is that the iron ammonium sulfate standard solution of CmoL/L carries out titration with concentration, writes down the volume VmL of institute's quota of expenditure solution;
C) V is exactly the volume that contains the iron ammonium sulfate standard solution of vanadium liquid consumption to be measured, and the content of vanadium is by formula
Calculate.
2. the means to save the situation of titration error during measuring vanadium by ferrous ammonium sulfate capacitance as claimed in claim 1, it is characterized in that: liquor potassic permanganate concentration is 15g/L～25g/L among the described step a.
3. the means to save the situation of titration error during measuring vanadium by ferrous ammonium sulfate capacitance as claimed in claim 1, it is characterized in that: sodium nitrite solution concentration is 15g/L～25g/L among the described step b, the urea addition is 0.5～1g.
4. the means to save the situation of titration error during measuring vanadium by ferrous ammonium sulfate capacitance as claimed in claim 1, it is characterized in that: the described full content of vanadium 1.00%～100% of vanadium liquid to be measured, the chromium content of containing is less than 1.00%.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN200710202815A CN100580450C (en) | 2007-11-30 | 2007-11-30 | Method for eliminating error in vanadium determination by ammonium ferrous sulfate volumetric method |
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| CN200710202815A CN100580450C (en) | 2007-11-30 | 2007-11-30 | Method for eliminating error in vanadium determination by ammonium ferrous sulfate volumetric method |
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| CN101173916A true CN101173916A (en) | 2008-05-07 |
| CN100580450C CN100580450C (en) | 2010-01-13 |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2010066190A1 (en) * | 2008-12-12 | 2010-06-17 | 江西稀有稀土金属钨业集团有限公司 | Method for measuring chromium content in a tungsten matrix which is added with chromium/chromium-vanadium |
| WO2010066191A1 (en) * | 2008-12-12 | 2010-06-17 | 江西稀有稀土金属钨业集团有限公司 | Method for measuring vanadium content in a tungsten matrix to which vanadium/chromium-vanadium has been added |
| CN101614719B (en) * | 2009-07-30 | 2011-04-13 | 攀钢集团钢铁钒钛股份有限公司 | Method for measuring content of vanadium by potassium permanganate oxidation-ferrous ammonium sulphate titrating method |
| CN104181158A (en) * | 2014-08-22 | 2014-12-03 | 武钢集团昆明钢铁股份有限公司 | Method for measuring concentration of tetravalent and pentavalent vanadium ions in vanadium battery electrolyte |
| CN107807124A (en) * | 2017-10-20 | 2018-03-16 | 河钢股份有限公司承德分公司 | Before a kind of high-alkali sodium vanadate crystallization in liquid vanadium concentration detection method |
| CN109655577A (en) * | 2018-12-25 | 2019-04-19 | 河钢股份有限公司承德分公司 | In sub-molten salt vanadium extracting process in sodium vanadate solution vanadium concentration detection method |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| SU1280540A1 (en) * | 1985-02-13 | 1986-12-30 | Научно-Исследовательский Институт Химии Саратовского Ордена Трудового Красного Знамени Государственного Университета Им.Н.Г.Чернышевского | Method of determining vanadium (iv) |
| SU1472822A1 (en) * | 1986-11-11 | 1989-04-15 | Московский институт тонкой химической технологии им.М.В.Ломоносова | Method of determining vanadium (iii,iv,v) in solid materials |
| CN1844892A (en) * | 2006-03-09 | 2006-10-11 | 太原理工大学 | Process for determining vanadium content in desulfurizing liquid |
-
2007
- 2007-11-30 CN CN200710202815A patent/CN100580450C/en not_active Expired - Fee Related
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2010066190A1 (en) * | 2008-12-12 | 2010-06-17 | 江西稀有稀土金属钨业集团有限公司 | Method for measuring chromium content in a tungsten matrix which is added with chromium/chromium-vanadium |
| WO2010066191A1 (en) * | 2008-12-12 | 2010-06-17 | 江西稀有稀土金属钨业集团有限公司 | Method for measuring vanadium content in a tungsten matrix to which vanadium/chromium-vanadium has been added |
| CN101614719B (en) * | 2009-07-30 | 2011-04-13 | 攀钢集团钢铁钒钛股份有限公司 | Method for measuring content of vanadium by potassium permanganate oxidation-ferrous ammonium sulphate titrating method |
| CN104181158A (en) * | 2014-08-22 | 2014-12-03 | 武钢集团昆明钢铁股份有限公司 | Method for measuring concentration of tetravalent and pentavalent vanadium ions in vanadium battery electrolyte |
| CN107807124A (en) * | 2017-10-20 | 2018-03-16 | 河钢股份有限公司承德分公司 | Before a kind of high-alkali sodium vanadate crystallization in liquid vanadium concentration detection method |
| CN109655577A (en) * | 2018-12-25 | 2019-04-19 | 河钢股份有限公司承德分公司 | In sub-molten salt vanadium extracting process in sodium vanadate solution vanadium concentration detection method |
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