CN112014379A - Method for measuring calcium oxide in limestone and dolomite - Google Patents
Method for measuring calcium oxide in limestone and dolomite Download PDFInfo
- Publication number
- CN112014379A CN112014379A CN202010503831.6A CN202010503831A CN112014379A CN 112014379 A CN112014379 A CN 112014379A CN 202010503831 A CN202010503831 A CN 202010503831A CN 112014379 A CN112014379 A CN 112014379A
- Authority
- CN
- China
- Prior art keywords
- sample
- standard
- mass
- strontium
- calcium
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/62—Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light
- G01N21/71—Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light thermally excited
- G01N21/73—Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light thermally excited using plasma burners or torches
Abstract
The invention discloses a method for measuring calcium oxide in limestone and dolomite, belonging to the technical field of ferrous metallurgy analysis. The invention melts the sample by using the lithium tetraborate-lithium metaborate (2+1) mixed flux, reduces the determination strength of calcium by using ICP-AES and Sr 407.771nm as an internal standard, can detect the content of calcium oxide in limestone and dolomite with higher content of calcium oxide, has the characteristics of wide determination range, high accuracy and high stability, and can provide accurate data for the smelting component control process.
Description
Technical Field
The invention belongs to the technical field of ferrous metallurgy analysis, and particularly relates to a method for measuring calcium oxide in limestone and dolomite.
Background
Limestone and dolomite are common metallurgical auxiliary materials and are mainly used as a slag former and a slag modifier in the steel-making and iron-making processes, and the chemical components of the limestone and the dolomite mainly contain calcium oxide, so that the calcium oxide components in the limestone and the dolomite need to be strictly controlled, and the chemical components of the limestone and the dolomite need to be accurately measured.
At present, the national standard GB/T3286-1998 for analyzing calcium oxide in limestone and dolomite adopts a conventional volumetric method, and has the defects of complicated operation steps, large workload, long detection period and the like. Related documents report that calcium and magnesium in mixed limestone are rapidly determined by an energy dispersive spectrometer, and Wuwein swallow and Tengchun research that calcium and magnesium in mixed limestone are determined by an energy dispersive X-ray fluorescence instrument. Dumisar and the like research ' microwave digestion-inductively coupled plasma emission spectroscopy ' and simultaneously determine iron, aluminum, calcium, magnesium, potassium, sodium and sulfur in dolomite '. Yanlixeng et al discuss "inductively coupled plasma atomic emission spectrometry method for simultaneously measuring iron, aluminium, calcium, magnesium and silicon in limestone", the method uses boric acid-sodium carbonate mixed flux to decompose sample, the salinity of solution is high, salting-out effect and interference are easily generated in the measuring process, and influence is brought to the result.
Disclosure of Invention
In view of one or more of the problems of the prior art, the present invention provides a method for determining calcium oxide in limestone or dolomite, comprising the steps of:
1) placing a sample with the mass m into a platinum crucible, adding lithium tetraborate-lithium metaborate (2+1) with the mass n into the platinum crucible, uniformly stirring the mixture and the sample, melting the mixture, and then cooling the mixture to room temperature to obtain a first mixed sample;
2) putting the first mixed sample into a glass beaker, sequentially adding hot water and hydrochloric acid for leaching, and then cooling to room temperature to obtain a second mixed sample;
3) transferring the third mixed sample into a volumetric flask, adding a strontium standard solution, diluting with high-purity water to a scale, shaking up to obtain a sample to be tested, synchronously performing blank comparison, and waiting for loading;
4) preparation of standard calibration curve solution: weighing 6 parts by mass of n lithium tetraborate-lithium metaborate (2+1), respectively placing the lithium tetraborate-lithium metaborate in a platinum crucible for melting, and then cooling to room temperature; then adding hot water and hydrochloric acid for leaching according to the step 2), transferring into a volumetric flask and adding a strontium standard solution according to the step 3), then respectively adding a calcium single element standard solution, diluting to a scale with high-purity water, shaking up, and preparing into a standard calibration curve solution containing 0%, 5.00%, 10.00%, 20.00%, 40.00% and 60.00 wt% of CaO in the solution;
5) measuring the calcium and strontium ion signal intensity by using an inductively coupled plasma emission spectrometer according to the standard correction curve solution obtained in the step 4), and drawing a standard curve according to the measurement result, wherein the analysis lines of calcium and strontium are 315.887nm and 407.771nm respectively;
6) and (3) measuring the sample to be measured and the blank contrast in the step 3) by using an inductively coupled plasma emission spectrometer, and obtaining the content of calcium oxide in the sample according to the standard curve obtained in the step 5).
In the method, the strontium in the step 5) is used as an internal standard element, the mass percent of CaO is used as a horizontal coordinate, and the signal intensity ratio of Ca ions and Sr ions is used as a vertical coordinate to draw a standard curve.
In the above method, the relationship between the mass m of the sample and the mass m of the lithium tetraborate-lithium metaborate (2+1) is m: n ═ 10 to 15: 1.
In the method, the temperature for melting the sample and the lithium tetraborate-lithium metaborate (2+1) in the step 1) is 1000-1100 ℃, and the melting time is 12-16 min.
In the method, the relationship between the amount of the hot water and the hydrochloric acid added in the step 2) and the mass of the sample is as follows: 1g of hot water, namely hydrochloric acid (sample 700-900 mL): 200-400 mL), wherein the temperature of the hot water is 75-85 ℃; the leaching temperature is 240-260 ℃.
In the method, the concentration of the strontium standard solution in the step 3) is 10 mug/mL, and the relation between the added amount and the mass of the sample is as follows: sample (40-60 mL) of the strontium standard solution was 1 g.
In the method, the concentration of the calcium single element standard solution in the step 4) is 1000 mug/mL.
The method for measuring calcium oxide in limestone and dolomite provided based on the technical scheme melts a sample by using the lithium tetraborate-lithium metaborate (2+1) mixed flux, reduces the measurement intensity of calcium by using ICP-AES and Sr 407.771nm as an internal standard, can detect the content of calcium oxide in limestone and dolomite with higher content of calcium oxide, has the characteristics of wide measurement range, high accuracy and high stability, and can provide accurate data for the smelting component control process. Compared with the prior art, the method has the following beneficial effects:
1) the invention utilizes the characteristics of low melting point and strong sample melting capability of lithium tetraborate-lithium metaborate (2+1), and can completely decompose the sample by using less flux. In addition, the method only uses a small amount of hydrochloric acid and a small amount of lithium tetraborate-lithium metaborate (2+1), can greatly reduce the using amount of the solvent and is beneficial to environmental protection.
2) Because the content of calcium oxide in limestone and dolomite is high, generally 28-38% of CaO in the dolomite and 40-55% of CaO in the limestone, when ICP-AES is used for direct measurement, the emission intensity of calcium is very high, the precision of a measurement result is poor, and the accuracy of the measurement result is low. According to the invention, Sr 407.771nm is used as an internal standard element, and the ratio of Ca ion strength to Sr ion strength is used as the determination strength, so that the determination strength of calcium can be reduced, the determination stability is improved, and the determination result has high sensitivity and is more accurate.
3) The method of the invention utilizes ICP-AES to carry out determination, calcium adopts horizontal observation, strontium adopts vertical observation mode, and the range of calcium oxide is determined: 0.50 to 55.0 weight percent of CaO. Therefore, the method can be suitable for analyzing limestone and dolomite samples with high CaO content. The invention eliminates matrix interference by adopting matrix matching, has the characteristics of wide linear range, high sensitivity, simple and convenient operation and accurate and reliable analysis result, and can provide reliable data for the detection of limestone and dolomite calcium oxide.
Detailed Description
The present invention will be described in detail with reference to specific examples.
The following reagents and equipment were used in the examples of the invention:
hydrochloric acid: the top grade is pure;
lithium tetraborate-lithium metaborate (2+1) guaranteed purity: mixing lithium tetraborate and lithium metaborate according to the mass ratio of 2: 1;
calcium single element standard solution: the concentration is 1000 mug/mL, and the product is from the national standard substance center;
a strontium carbonate reference substance; the top grade pure hydrochloric acid is used for preparing a strontium standard solution, and the concentration is 10 mug/mL;
a 250mL volumetric flask; 300mL beaker;
argon gas: the purity of argon is more than or equal to 99.9 percent;
the inductively coupled plasma emission spectrometer is of the type of Optima 5300DV of PE company; the observation mode is as follows: calcium horizontal observation and strontium vertical observation. And preferably determining the analysis lines for calcium and strontium as: 315.887nm and 407.771nm, wherein Ca is an analysis element, and Sr is an internal standard element.
The method comprises the following steps:
1) weighing 0.1000g of sample into a cleaned and dried platinum crucible, adding 1.2g of mixed solvent of lithium tetraborate and lithium metaborate (2+1), placing the platinum crucible containing the sample in a muffle furnace at 1000 ℃ for melting for 15min, taking out, and cooling to room temperature in a dryer.
2) And placing the cooled sample into a 300mL glass beaker, adding 80mL of hot water at 80 ℃ and 30mL of hydrochloric acid in sequence, leaching the sample frit at the low temperature of 250 ℃, taking down and cooling to room temperature. After cooling, transferring the sample into a 250mL volumetric flask, adding 5mL of strontium standard solution (10 mu g/mL), diluting with high-purity water to a scale, shaking up, taking the sample as a sample to be detected, and waiting for loading on the machine. Blank control experiments were performed along with the test.
3) Preparation of standard calibration curve solution
Weighing 6 parts of 1.2g lithium tetraborate-lithium metaborate (2+1) mixed flux in a cleaned and dried platinum crucible, placing the platinum crucible in a muffle furnace at 1000 ℃ for melting for 15min, taking out the platinum crucible, and cooling the platinum crucible to room temperature in a dryer. The cooled platinum crucible is placed in a 300mL glass beaker, 80mL of hot water at 80 ℃ and 30mL of hydrochloric acid are sequentially added, the sample frit is leached at the low temperature of 250 ℃, taken down, cooled to room temperature, transferred into a 250mL volumetric flask, and 5mL of strontium standard solution (10 mug/mL) is added. Adding standard solution of calcium single element, diluting with high-purity water to scale, shaking, and preparing into solution containing CaO 0, 5.00, 10.00, 20.00, 40.00, and 55.00 wt%. This solution was used for preparing a standard curve.
4) Drawing of standard curve
And determining Ca 315.887nm and Sr 407.771nm as analytical lines. Ca is an analysis element, and Sr is an internal standard element.
And introducing the standard correction curve solution into an inductively coupled plasma emission spectrometer, measuring the signal intensity of Ca and Sr ions, taking the signal intensity ratio of the Ca and Sr ions as the measured intensity, and drawing a calibration curve by taking the mass percent of CaO as an abscissa and the signal intensity ratio of the Ca and Sr ions as an ordinate.
Preparing a standard curve according to the methodCorrelation coefficient r is greater than 0.999, and 11 parts of blank solution are prepared according to the experimental method and are measured by 3 times according to the detection limit formula C defined by International Union of Pure and Applied Chemistry (IUPAC)L＝3Sb/k(SbStandard deviation of blank, k is corresponding calibration curve slope) was calculated to have a detection limit CaO of 0.010%.
5) And introducing the sample solution and the blank sample solution into an inductively coupled plasma emission spectrometer, measuring the ratio of the Ca ion intensity to the Sr ion intensity, and calculating the content of calcium oxide in the sample solution according to a standard solution calibration curve with known mass percentage.
The content of each element in the sample is calculated according to the following formula:
W＝Wi-W0
in the formula: w represents the mass percentage of calcium oxide in the sample;
w0-mass percent calcium oxide in blank;
the mass percentage of the Wi-calcium oxide in the sample to be detected;
detection range: 0.50 to 55.0 weight percent of CaO.
Example 1
The standard samples limestone (YSBC28712-93), (GBW07125a), (BH0120-4W), dolomite (YSBC11703-95) and (BH191-4) are weighed and determined according to the method, and the results are shown in the following Table 1.
Table 1: results of measurement of standard samples
Example 2
Weighing limestone and dolomite sample 1#、2#、3#、4#、5#The results are shown in Table 2, and are determined according to the methods described above and the Enterprise Standard QJH/BG-05-203-2000 (sodium carbonate-sodium tetraborate melt-volume method).
Table 2: limestone and dolomite sample determination results
The results shown in the tables 1 and 2 show that the method is used for measuring calcium oxide in limestone and dolomite, and by utilizing the characteristics of low melting point and strong sample melting capacity of lithium tetraborate-lithium metaborate (2+1), the sample can be completely decomposed by using less flux, and the lithium tetraborate-lithium metaborate has no background interference during measurement, so that the measurement result has high sensitivity and more accurate result; the ICP-AES is used for determination, Sr 407.771nm is used as an internal standard element, and the ratio of the Ca ion strength to the Sr ion strength is used as the determination strength, so that the determination strength of calcium is reduced, the determination stability is improved, the determination result sensitivity is high, and the result is more accurate.
The measurement is carried out by utilizing ICP-AES, calcium is horizontally observed, strontium is vertically observed, and the range of calcium oxide (CaO 0.50-55.0 wt%) is more suitable for the analysis of limestone and dolomite samples with higher CaO content. The invention has good application effect through multiple tests on limestone and dolomite samples. The invention eliminates matrix interference by adopting matrix matching, has the characteristics of wide linear range, high sensitivity, simple and convenient operation and accurate and reliable analysis result, and can provide reliable data for the detection of limestone and dolomite calcium oxide.
Finally, it should be noted that: although the present invention has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that changes may be made in the embodiments and/or equivalents thereof without departing from the spirit and scope of the invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (7)
1. A method for determining calcium oxide in limestone and dolomite comprises the following steps:
1) placing a sample with the mass m into a platinum crucible, adding lithium tetraborate-lithium metaborate (2+1) with the mass n into the platinum crucible, uniformly stirring the mixture and the sample, melting the mixture, and then cooling the mixture to room temperature to obtain a first mixed sample;
2) putting the first mixed sample into a glass beaker, sequentially adding hot water and hydrochloric acid for leaching, and then cooling to room temperature to obtain a second mixed sample;
3) transferring the third mixed sample into a volumetric flask, adding a strontium standard solution, diluting with high-purity water to a scale, shaking up to obtain a sample to be tested, synchronously performing blank comparison, and waiting for loading;
4) preparation of standard calibration curve solution: weighing 6 parts by mass of n lithium tetraborate-lithium metaborate (2+1), respectively placing the lithium tetraborate-lithium metaborate in a platinum crucible for melting, and then cooling to room temperature; then adding hot water and hydrochloric acid for leaching according to the step 2), transferring into a volumetric flask and adding a strontium standard solution according to the step 3), then respectively adding a calcium single element standard solution, diluting to a scale with high-purity water, shaking up, and preparing into a standard calibration curve solution containing 0%, 5.00%, 10.00%, 20.00%, 40.00% and 60.00 wt% of CaO in the solution;
5) measuring the calcium and strontium ion signal intensity by using an inductively coupled plasma emission spectrometer according to the standard correction curve solution obtained in the step 4), and drawing a standard curve according to the measurement result, wherein the analysis lines of calcium and strontium are 315.887nm and 407.771nm respectively;
6) and (3) measuring the sample to be measured and the blank contrast in the step 3) by using an inductively coupled plasma emission spectrometer, and obtaining the content of calcium oxide in the sample according to the standard curve obtained in the step 5).
2. The method according to claim 1, wherein the strontium in the step 5) is used as an internal standard element, the mass percent of CaO is used as an abscissa, and the signal intensity ratio of Ca and Sr ions is used as an ordinate to draw a standard curve.
3. The method according to claim 1 or 2, wherein the relationship between the mass m of the sample and the mass m of the lithium tetraborate-lithium metaborate (2+1) is m: n ═ 10 to 15: 1.
4. The method according to claim 1 or 2, wherein the temperature for melting the sample and the lithium tetraborate-lithium metaborate (2+1) in step 1) is 1000 to 1100 ℃ and the melting time is 12 to 16 min.
5. The method according to claim 1 or 2, wherein the amount of hot water, hydrochloric acid added in step 2) is related to the mass of the sample by: 1g of hot water, namely hydrochloric acid (sample 700-900 mL): 200-400 mL), wherein the temperature of the hot water is 75-85 ℃; the leaching temperature is 240-260 ℃.
6. The method according to claim 1 or 2, wherein the concentration of the strontium standard solution in step 3) is 10 μ g/mL, and the relationship between the amount added and the mass of the sample is: sample (40-60 mL) of the strontium standard solution was 1 g.
7. The method according to claim 1 or 2, wherein the concentration of the standard solution of calcium single element in step 4) is 1000 μ g/mL.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010503831.6A CN112014379A (en) | 2020-06-05 | 2020-06-05 | Method for measuring calcium oxide in limestone and dolomite |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010503831.6A CN112014379A (en) | 2020-06-05 | 2020-06-05 | Method for measuring calcium oxide in limestone and dolomite |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN112014379A true CN112014379A (en) | 2020-12-01 |
Family
ID=73506672
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010503831.6A Pending CN112014379A (en) | 2020-06-05 | 2020-06-05 | Method for measuring calcium oxide in limestone and dolomite |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112014379A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113984819A (en) * | 2021-10-08 | 2022-01-28 | 山东莱钢永锋钢铁有限公司 | Raw dolomite high-temperature melting X fluorescence measurement method |
| CN115684136A (en) * | 2022-10-28 | 2023-02-03 | 湖南稀土金属材料研究院有限责任公司 | Method for measuring content of calcium oxide in samarium oxide |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102252880A (en) * | 2010-05-19 | 2011-11-23 | 攀钢集团钢铁钒钛股份有限公司 | Digestion method and detection method of iron ore |
| CN111122549A (en) * | 2020-01-06 | 2020-05-08 | 包头钢铁（集团）有限责任公司 | Method for measuring magnesium oxide, potassium oxide, manganese oxide, titanium oxide and silicon dioxide in limestone and dolomite |
-
2020
- 2020-06-05 CN CN202010503831.6A patent/CN112014379A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102252880A (en) * | 2010-05-19 | 2011-11-23 | 攀钢集团钢铁钒钛股份有限公司 | Digestion method and detection method of iron ore |
| CN111122549A (en) * | 2020-01-06 | 2020-05-08 | 包头钢铁（集团）有限责任公司 | Method for measuring magnesium oxide, potassium oxide, manganese oxide, titanium oxide and silicon dioxide in limestone and dolomite |
Non-Patent Citations (1)
| Title |
|---|
| 曹宏燕: "《冶金材料分析技术与应用》", 30 September 2008, 冶金工业出版社 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113984819A (en) * | 2021-10-08 | 2022-01-28 | 山东莱钢永锋钢铁有限公司 | Raw dolomite high-temperature melting X fluorescence measurement method |
| CN115684136A (en) * | 2022-10-28 | 2023-02-03 | 湖南稀土金属材料研究院有限责任公司 | Method for measuring content of calcium oxide in samarium oxide |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN102253030A (en) | Method for determining impurity content in high-titanium slag | |
| CN107976481B (en) | Method for detecting scandium content in traditional Chinese medicinal materials | |
| CN103604823A (en) | Method for measuring contents of potassium, sodium, lead and zinc in iron ore | |
| CN110514643B (en) | Method for measuring trace elements in high-purity magnesium-based oxide by inductively coupled plasma emission spectrometry | |
| CN112014379A (en) | Method for measuring calcium oxide in limestone and dolomite | |
| CN102393371B (en) | Sample processing method for detecting boron in industrial silicon with graphite furnace atomic absorption spectrometry | |
| CN113295676A (en) | Method for measuring calcium, aluminum and barium in deoxidizer | |
| CN106990098A (en) | The method of each element content in simultaneous determination aluminium electrolyte | |
| CN111122549A (en) | Method for measuring magnesium oxide, potassium oxide, manganese oxide, titanium oxide and silicon dioxide in limestone and dolomite | |
| CN104422685A (en) | Method for determining content of metal aluminum in ladle slag modifying agent | |
| CN112924483A (en) | Method for measuring content of chlorine element in glass | |
| CN107389716A (en) | The method of impurity in x-ray fluorescence spectrometry Copper Ores | |
| CN114739982A (en) | Method for detecting element content in glass | |
| CN112129744B (en) | Chemical phase analysis method for lithium in ore | |
| CN112179896B (en) | Chemical phase analysis method for rubidium in metal ore | |
| CN113533307A (en) | Method for measuring contents of calcium, magnesium, copper, aluminum, manganese, titanium, potassium, sodium, lead and zinc elements in blast furnace dust | |
| JPS6362695B2 (en) | ||
| CN106872446A (en) | A kind of method for determining chromic oxide content in slugging flux | |
| CN110715913A (en) | Method for measuring selenium in geochemical sample by atomic fluorescence spectrometry | |
| CN111239172A (en) | Method for determining phosphorus content in coal | |
| CN116735565A (en) | Method for measuring barium by internal standard-ICP-OES | |
| CN110412116A (en) | The test method and its application of sulfur content | |
| CN110631874A (en) | Sample pretreatment method for determining content of silicon element in polymer and method for determining content of silicon element in polymer | |
| CN107037038A (en) | The method of each element content in simultaneous determination aluminium electrolyte | |
| CN109668872A (en) | A kind of direct-reading spectrometer surveys the analysis method of nitrogen in steel online |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20201201 |