Method for detecting selenium element in soda-lime-silica glass
阅读说明：本技术 一种钠钙硅玻璃中硒元素的检测方法 (Method for detecting selenium element in soda-lime-silica glass ) 是由 黄秀辉 候英兰 洪伟强 徐兴军 郑志勇 何梅 于 2020-12-28 设计创作，主要内容包括：本发明公开了一种钠钙硅玻璃中硒元素的检测方法,取一组不同梯度硒含量的含硒的钠钙硅玻璃标准样品粉末,压片制样,进行XRF检测,以标准样品的硒元素含量和XRF检测值建立荧光工作曲线,作为钠钙硅玻璃中硒元素的标准曲线；取待测样品粉末,压片制样,进行XRF检测,代入所述标准曲线中,得到待测样品中的硒含量。本发明的检测方法离散性好,精密度高,基体效应小,检出限低,结果可信度高,能够满足生产检测需要。(The invention discloses a method for detecting selenium in soda-lime-silica glass, which comprises the steps of taking a group of selenium-containing soda-lime-silica glass standard sample powder with different gradient selenium contents, tabletting and preparing a sample, carrying out XRF detection, and establishing a fluorescence working curve by using the selenium content of the standard sample and the XRF detection value as a standard curve of the selenium in the soda-lime-silica glass; and taking powder of a sample to be detected, tabletting and preparing the sample, carrying out XRF detection, and substituting the XRF detection into the standard curve to obtain the selenium content in the sample to be detected. The detection method disclosed by the invention has the advantages of good discreteness, high precision, small matrix effect, low detection limit and high result reliability, and can meet the production detection requirements.)
1. A method for detecting selenium element in soda-lime-silica glass is characterized by comprising the following steps: the method comprises the following steps:
1) taking a group of selenium-containing soda-lime-silica glass standard sample powder with different gradient selenium contents, and tabletting to prepare samples;
2) performing XRF detection on the pressed sheet of the standard sample, and establishing a fluorescence working curve by using the selenium content of the standard sample and the XRF detection value as a standard curve of the selenium in the soda-lime-silica glass;
3) and taking powder of a sample to be detected, tabletting and preparing the sample, carrying out XRF detection, and substituting the XRF detection into the standard curve to obtain the selenium content in the sample to be detected.
2. The method for detecting selenium in soda-lime-silica glass as claimed in claim 1, wherein: the preparation method of the sample powder comprises the following steps: grinding the sample until the particle size is not more than 75 mu m, drying the sample at 105-110 ℃ for 1.5-2.5 hours, and naturally cooling the sample to obtain the nano-silver particles.
3. The method for detecting selenium in soda-lime-silica glass as claimed in claim 1, wherein: the tabletting method comprises the following steps: uniformly mixing sample powder and a binder, tabletting, wherein the weight ratio of the sample powder to the binder is (1-5): 0.8 to 1.2.
4. The method for detecting selenium in soda-lime-silica glass as claimed in claim 1, wherein: the tabletting adopts a boric acid bedding tabletting method, and the weight ratio of the sample powder, the binder and boric acid is 1-5: 0.8-1.2: 4 to 4.5.
5. The method for detecting selenium in soda-lime-silica glass as claimed in claim 3 or 4, wherein: the binder comprises at least one of stearic acid, microcrystalline cellulose, boric acid, or starch.
6. The method for detecting selenium in soda-lime-silica glass as claimed in claim 1, wherein: the standard sample is GBW03117 soda-lime-silica glass, and selenium powder is added according to the required selenium content.
7. The method for detecting selenium in soda-lime-silica glass as claimed in claim 1, wherein: in the group of standard samples with different gradient selenium contents, the selenium contents are respectively as follows: 0. 4.8 to 5.2ppm, 9.8 to 10.2ppm, 19.8 to 20.2ppm, 49.8 to 50.2ppm and 99.8 to 100.2ppm, or: 0. 19.8 to 20.2ppm, 39.8 to 40.2ppm, 59.8 to 60.2ppm, 79.8 to 80.2ppm and 99.8 to 100.2 ppm.
8. The method for detecting selenium in soda-lime-silica glass as claimed in claim 1, wherein: the XRF detection instrument is a Malverpa napaceae Axios MAX X-ray fluorescence spectrometer.
9. The method for detecting selenium in soda-lime-silica glass as claimed in claim 8, wherein: the measurement conditions of the selenium element are as follows:
10. the method for detecting selenium in soda-lime-silica glass as claimed in claim 1, wherein: the soda-lime-silica glass comprises blue gray glass, European gray glass or crystal gray glass.
Technical Field
The invention belongs to the technical field of analytical chemistry, and particularly relates to detection of selenium.
Background
Selenium or selenium compounds are an important colorant in the production of gray glass, but selenium is not stable in coloring, has a melting point of 220 ℃ and a boiling point of 685 ℃, has relatively strong volatility, and is easy to cause selenium loss in the glass melting process, so that the content of the selenium or selenium compounds needs to be accurately quantified in the process of changing materials or controlling production so as to add the colorant in time to reduce the problems of glass color difference and the like.
With the continuous progress of modern science and technology and the continuous improvement of the living standard of people, consumers pay more and more attention to the appearance and the quality of glass. If the glass with the color difference of more than 0.5 (the color difference has no unit and is a pure numerical value) is installed on a building, the problem of the color difference (the color depth) of the glass can be identified by naked eyes without using an instrument for detection. Therefore, the color difference of the glass is an important index affecting the appearance quality of the glass.
However, in terms of detection, the chemical titration method, the atomic absorption method, the plasma emission spectrometry and other detection methods adopted in GB/T1347-2008 Na-Ca-Si glass chemical analysis method do not relate to the detection of selenium (Se) element; the patent literature on detection reports that the trace selenium element in the glass is measured by plasma emission spectrometry (ICP), but the analysis time is long and the result data is unstable. Reason analysis: firstly, the selenium (Se) content is low and reaches the ppm level, and the detection is not good; secondly, because the chemical titration method, the atomic absorption method or the plasma emission spectrometry method need to pretreat the sample to be tested, such as high-temperature acid dissolution or high-temperature melting, the volatilization of selenium is uncontrollable due to the high-temperature process, so that the measurement result is unstable and the data is inaccurate. Therefore, the prior art cannot provide a detection standard which is convenient and fast and has high accuracy.
At present, the current method in the glass industry indirectly and reversely deduces the change trend of Se content in glass by using an empirical formula through an actual formula and a phototropism detection result, and the change trend has a certain error with the actual content because the Se content component fluctuation of the glass is a sufficient unnecessary condition of phototropism change (red-green color difference of a color coordinate a value). That is, an increase in the Se content may cause an increase in the a value, but an increase in the a value may not necessarily be caused by an increase in the Se content, but may be caused by a decrease in the Fe content. Therefore, the result of the optical detection cannot truly and accurately reflect the change of Se content in the glass.
In conclusion, the detection and analysis of Se content in glass are an important research both from market feedback and from actual production requirements.
Disclosure of Invention
The invention aims to overcome the defects of the prior art and provides a method for detecting selenium in soda-lime-silica glass. According to the invention, through technical research and development and creation, the detection requirement of enterprises on selenium element in the colored glass is met, and the colored glass produced by the enterprises can be tracked, fed back and accurately measured in time, so that the color stability of the produced glass is ensured, and the method has important significance for improving the quality of the glass.
The technical scheme adopted by the invention for solving the technical problems is as follows:
a method for detecting selenium element in soda-lime-silica glass comprises the following steps:
1) taking a group of selenium-containing soda-lime-silica glass standard sample powder with different gradient selenium contents, and tabletting to prepare samples;
2) performing XRF detection on the pressed sheet of the standard sample, and establishing a fluorescence working curve by using the selenium content of the standard sample and the XRF detection value as a standard curve of the selenium in the soda-lime-silica glass;
3) and taking powder of a sample to be detected, tabletting and preparing the sample, carrying out XRF detection, and substituting the XRF detection into the standard curve to obtain the selenium content in the sample to be detected.
In one embodiment: the preparation method of the sample powder comprises the following steps: grinding the sample to a particle size of not more than 75 microns (sieving the sample with a 200-mesh sieve with a pore size of 75 microns), drying the sample at 105-110 ℃ for 1.5-2.5 hours, and naturally cooling the dried sample to obtain the nano-particles.
In one embodiment: the tabletting method comprises the following steps: uniformly mixing sample powder and a binder, tabletting, wherein the weight ratio of the sample powder to the binder is (1-5): 0.8 to 1.2. And pressing the sheet at room temperature to prepare a sample, so as to avoid the influence of high temperature on component change.
In one embodiment: the tabletting adopts a boric acid bedding tabletting method, and the weight ratio of the sample powder, the binder and boric acid is 1-5: 0.8-1.2: 4 to 4.5.
In one embodiment: the binder comprises at least one of stearic acid, microcrystalline cellulose, boric acid, or starch.
In one embodiment: the standard sample is GBW03117 soda-lime-silica glass, and selenium powder is added according to the required selenium content. The selenium powder is high-purity reagent selenium powder (the selenium content is not less than 99.95%).
In one embodiment: in the group of standard samples with different gradient selenium contents, the selenium contents are respectively as follows: 0. 4.8 to 5.2ppm, 9.8 to 10.2ppm, 19.8 to 20.2ppm, 49.8 to 50.2ppm and 99.8 to 100.2ppm, or: 0. 19.8 to 20.2ppm, 39.8 to 40.2ppm, 59.8 to 60.2ppm, 79.8 to 80.2ppm and 99.8 to 100.2 ppm.
In one embodiment: the XRF detection instrument is a Malverpa napaceae Axios MAX X-ray fluorescence spectrometer.
In one embodiment: the measurement conditions of the selenium element are as follows:
in one embodiment: the soda-lime-silica glass comprises blue gray glass, European gray glass or crystal gray glass and other gray glass.
The equipment, reagents, processes, parameters and the like related to the invention are conventional equipment, reagents, processes, parameters and the like except for special description, and no embodiment is needed.
All ranges recited herein include all point values within the range.
In the present invention,% s are weight percentages unless otherwise specified.
In the invention, the room temperature, namely the normal environment temperature, can be 10-30 ℃.
Compared with the background technology, the technical scheme has the following advantages:
1. the invention adopts a tabletting method to prepare the sample, is simple and easy to implement, ensures the accuracy of the set value of the selenium in the standard sample, and solves the problem of the standard sample of the fluorometer.
2. The fluorometer established by the invention has good measurement curve linearity, can quickly and accurately measure the selenium content in the glass, perfects the monitoring and analyzing means for the glass and solves the technical barrier of the enterprise to the detection of the selenium element in the colored glass.
3. Once the measurement curve of the fluorometer is established, other unknown incoming samples can be accurately and quickly measured and compared by only periodically correcting drift.
4. The invention can detect and track and feed back the selenium content (especially blue gray, European gray, crystal gray glass and other gray glass) in time, and has important significance for stable production and glass quality improvement.
5. The invention can be used as a standard version and popularized to the glass industry and the related fields.
Drawings
FIG. 1 is a graph showing the trend lines established in example 1 based on the Se set values and XRF measurement values of 1# -6 # standard samples.
FIG. 2 is a graph showing the operating curve of the fluorescence spectrometer obtained in example 1, wherein the abscissa Se (%) is the concentration of selenium and the ordinate Se (kcps) is the fluorescence line intensity of XRF selenium.
Detailed Description
The invention is further illustrated by the following figures and examples.
Example 1: establishment of method for detecting selenium element in soda-lime-silica glass
The method for detecting the selenium element in the soda-lime-silica glass comprises the following steps:
1. preparation of Standard samples
Preparing a group of selenium-containing glass standard samples with different gradient content ranges;
the instrument comprises the following steps: an electronic balance of the Japan Shimadzu AUY220 model, Nantong Jiacheng 101-1A air-blast drying oven.
Chemical reagents: national first-grade standard substance GBW03117 soda-lime-silica glass, high-purity reagent selenium powder (99.95%).
TABLE 1 GBW03117 index for soda-lime-silica glass
Soda-lime-silica glass
SiO2
Al2O3
Fe2O3
TiO2
CaO
MgO
K2O
Na2O
SO3
L.O.I
GBW03117
71.25
2.56
0.18
0.057
6.37
3.98
1.1
13.77
0.17
0.44
The formula of the standard sample directly adopts GBW03117 soda-lime-silica glass instead of the combination of pure silicon dioxide, aluminum oxide, magnesium oxide, calcium carbonate, sodium carbonate and other chemical reagents, and the main purpose is to simply weigh the sample and more importantly ensure the similarity of a matrix between the actual production measurement sample and the standard sample.
Grinding the reagents until the reagents pass through a sieve with the aperture of 75 mu m (200 meshes), then placing the samples into a weighing dish, drying the samples for 2 hours in a blowing drying oven at 105-110 ℃, taking out the samples, and placing the samples in a dryer for natural cooling for later use. Weighing 99.95% selenium powder, diluting with GBW03117 soda-lime-silica glass, and preparing into 4-6 parts of standard samples with the same concentration, wherein each 1 part of standard samples contains 0-0.0001 part of Se element by weight. For example: 10g of a standard sample with the selenium content of 100ppm (0.01%) is prepared, and 0.001g of selenium powder and 9.999g of soda-lime-silica glass are needed; 10g of a standard sample with the selenium content of 50ppm (0.005%) is prepared, and 0.0005g of selenium powder and 9.9995g of soda-lime-silica glass are needed; 10g of a standard sample with the selenium content of 20ppm (0.002%) is prepared, and 0.0002g of selenium powder and 9.9998g of soda-lime-silica glass are needed; 10g of a standard sample with the selenium content of 10ppm (0.001%) is prepared, and 0.0001g of selenium powder and 9.9999g of soda-lime-silica glass are needed; 20g of a standard sample with the selenium content of 5ppm (0.0005%) is prepared, and 0.0001g of selenium powder and 19.9999g of soda-lime-silica glass are required; 10g of standard sample with selenium content of 0ppm is prepared, and 10g of soda-lime-silica glass can be directly weighed without adding selenium powder. The appropriate gradient adjustment can be made according to the concentration of the sample, and the adjustment basis is as follows: the concentration of the sample to be measured falls optimally within the range of the standard sample of the curve.
TABLE 2 formulation of Standard and unknown samples
Description of the drawings:
1)1 part by weight is 1 g. The samples # 5 and # 7 increased the overall weight of the standard sample due to the selenium concentration being too low and the balance weighing accuracy being limited (0.0001 g).
2)1# to 6# is used as a standard sample for establishing a fluorometer curve, 7# to 8# is used as an unknown sample, then the unknown sample is measured by the curve established by the 1# to 6# standard sample, and the measurement result is compared with the set value of the unknown sample.
3)W＝m2/(m1+m2) X 100% (the formula is a general formula)
Wherein W is the selenium content in the sample, m1M is the weight of soda-lime-silica glass2Is the weight of selenium powder.
The above are 6 data of 0, 5ppm, 10ppm, 20ppm, 50ppm and 100ppm of selenium powder, and W is calculated as m2/(m1+m2) Obtaining soda-lime-silica glass m by multiplying by 100%1(g) The corresponding numerical value of (c). The content of the selenium powder in the standard sample can be adjusted in a proper gradient mode according to the concentration of the sample to be detected, so that the concentration of the sample to be detected is in the range of the curve standard sample to be optimal. For example, it can be adjusted as: 0. 20ppm, 40ppm, 60ppm, 80ppm, 100ppm, and the like.
2. Tabletting sample preparation
The instrument comprises the following steps: shanghai full-force SL201 type semi-automatic sample pressing machine
Chemical reagents: stearic acid (analytically pure), boric acid (analytically pure).
1# standard sample tabletting: 3 parts by weight of the No. 1 standard sample and 0.6 part by weight of the bonding agent stearic acid are respectively weighed and ground in an agate mortar for uniform mixing for later use. The ratio of the sample to the stearic acid serving as a binder can be 1: 1-5: 1, and considering that the selenium content of the sample is too low, the ratio of 5:1 is preferably selected to ensure good caking property during tabletting and increase the peak-to-back ratio during selenium detection.
Weighing 7 parts by weight of boric acid, edging and bottoming the boric acid on a sample press, and keeping the pressure for 20 seconds at 30 tons.
Remarking: the setting of the pressure and the pressure maintaining time can be set according to different parameters of different model numbers of the sample pressing machine, and the sample is not easy to loosen as long as the sample can be pressed and formed.
And (4) sticking a label on the non-measuring surface, and storing the label in a dryer to be measured so as to prevent moisture absorption and pollution. Note: only the edge of the sample wafer can be held to avoid contamination of the X-ray measurement surface.
2# standard sample tabletting: 3 parts by weight of 2# standard sample and 0.6 part by weight of bonding agent stearic acid are respectively weighed and ground in an agate mortar for uniform mixing for later use. Weighing 7 parts by weight of boric acid, edging and bottoming the boric acid on a sample press, and keeping the pressure for 20 seconds at 30 tons.
And (4) sticking a label on the non-measuring surface, and storing the label in a dryer to be measured so as to prevent moisture absorption and pollution.
Tabletting # 3 standard sample: 3 parts by weight of the No. 3 standard sample and 0.6 part by weight of the bonding agent stearic acid are respectively weighed and ground in an agate mortar for uniform mixing for later use. Weighing 7 parts by weight of boric acid, edging and bottoming the boric acid on a sample press, and keeping the pressure for 20 seconds at 30 tons.
And (4) sticking a label on the non-measuring surface, and storing the label in a dryer to be measured so as to prevent moisture absorption and pollution.
4# standard sample tabletting: 3 parts by weight of the No. 4 standard sample and 0.6 part by weight of the bonding agent stearic acid are respectively weighed and ground in an agate mortar for uniform mixing for later use. Weighing 7 parts by weight of boric acid, edging and bottoming the boric acid on a sample press, and keeping the pressure for 20 seconds at 30 tons.
And (4) sticking a label on the non-measuring surface, and storing the label in a dryer to be measured so as to prevent moisture absorption and pollution.
5# standard sample tabletting: 3 parts by weight of the No. 5 standard sample and 0.6 part by weight of the bonding agent stearic acid are respectively weighed and ground in an agate mortar for uniform mixing for later use. Weighing 7 parts by weight of boric acid, edging and bottoming the boric acid on a sample press, and keeping the pressure for 20 seconds at 30 tons.
And (4) sticking a label on the non-measuring surface, and storing the label in a dryer to be measured so as to prevent moisture absorption and pollution.
6# Standard sample tabletting: 3 parts by weight of the No. 6 standard sample and 0.6 part by weight of the bonding agent stearic acid are respectively weighed and ground in an agate mortar for uniform mixing for later use. Weighing 7 parts by weight of boric acid, edging and bottoming the boric acid on a sample press, and keeping the pressure for 20 seconds at 30 tons.
And (4) sticking a label on the non-measuring surface, and storing the label in a dryer to be measured so as to prevent moisture absorption and pollution.
Samples # 7 and # 8 were prepared using the same tabletting procedure as above.
3. Establishing a fluorometer measurement curve
The instrument comprises the following steps: malverpa napaceae Axios MAX X-ray fluorescence spectrometer
TABLE 3 measurement conditions of elemental selenium
Detection limit LLD: 0.644ppm
Measuring 1# to 6# standard samples respectively (comparing the data measured by the XRF instrument as follows), calculating the set value of Se (namely the actual content of Se in the standard sample) and the slope and intercept of the curve of the XRF detection value and the correlation coefficient,
se set value and XRF detection value of standard samples of 41 # to 6# in table
Serial number
Se setting value (ppm)
XRF detection (ppm)
1#
100
100.6
2#
50
49.5
3#
20
20.4
4#
10
9.6
5#
5
4.7
6#
0
0
The trend lines established from the Se set values and XRF test values of the 1# -6 # standard samples are shown in FIG. 1: intercept: 0, slope 1.0029, correlation coefficient R20.9999 is more than 0.999, which shows good linearity and reliable measurement value.
The fluorometer operating curve is shown in FIG. 2. Within a certain range, the element concentration and the line intensity are in a linear relationship, and the linear regression equation C is D + E R, where D and E are determined from the linear regression equation, i.e., C is 0.00007+ 0.00084R. The working curve is a standard curve for measuring the selenium element in the glass. Once the curve is established, other unknown samples can be accurately and quickly measured only by regular drift correction. Compared with an inductively coupled plasma emission spectrometry, the time from sample preparation to measurement needs 1.5-2 days, and the measurement task can be completed only by 0.5 day by adopting a tabletting method.
4. Measuring unknown samples
And (4) directly measuring the 7# and 8# samples (tabletting is finished in the step 2) by using the working curve established in the step 3 to obtain measurement data. The measured values were compared to the set point data as follows:
se set value and XRF detection value of samples in tables 57 # to 8#
Serial number
Set value (ppm)
XRF detection (ppm)
Error (ppm)
7#
15
14.5
0.5
8#
30
30
0
The difference between the measured value of the XRF in the table above and the set value is less than 1ppm, and the working curve is further verified to meet the measurement requirement.
Example 2
The blue-gray glass sample was subjected to 5 replicates according to the detection method of example 1. The sample lot numbers are 180622-1-180622-5.
The first step is as follows: glass sample
And (3) breaking and grinding the blue gray glass sample until the blue gray glass sample passes through a sieve with the aperture of 75 mu m (200 meshes), then placing the sample in a weighing dish, drying the sample in a forced air drying box at the temperature of 105-110 ℃ for 2 hours, taking out the sample, and naturally cooling the sample in a dryer for later use.
3 parts of the powder and 0.6 part of the bonding agent stearic acid are respectively weighed and ground in an agate mortar for uniform mixing for later use.
The second step is that: tabletting sample preparation
Weighing 7 parts by weight of boric acid, edging and bottoming the boric acid on a sample press, and keeping the pressure for 20 seconds at 30 tons.
And (4) sticking a label on the non-measuring surface, and storing the label in a dryer to be measured so as to prevent moisture absorption and pollution.
Repeating the sample preparation step for 5 times to prepare 5 parallel samples, and measuring by a fluorimeter.
The third step: comparison of measurements
The results of the repeatability measurements are shown in table 6:
TABLE 6 repeatability test of blue-gray glass samples
Sample batch number
Se/ppm
180622-1
9.5
180622-2
9.2
180622-3
8.4
180622-4
8.8
180622-5
9.1
Mean value of
9
Standard deviation S2
0.175
Standard deviation S
0.42
Relative standard deviation RSD%
4.65
In Table 6, the blue-gray glass samples had a mean selenium content of 9ppm and a relative standard deviation of 4.65% RSD. The smaller the relative standard deviation RSD%, the better, generally not more than 5%, meets the measurement requirements.
Example 3
The european gray glass sample was subjected to 5 replicates according to the detection method of example 1. The sample lot numbers are 180410-1-180410-5.
The first step is as follows: glass sample
Breaking and grinding the European gray glass sample until the European gray glass sample passes through a sieve with the aperture of 75 mu m (200 meshes), then putting the sample into a weighing dish, drying the sample in an air-blast drying box at the temperature of 105-110 ℃ for 2 hours, taking out the sample, and naturally cooling the sample in a dryer for later use.
3 parts of the powder and 0.6 part of the bonding agent stearic acid are respectively weighed and ground in an agate mortar for uniform mixing for later use.
The second step is that: tabletting sample preparation
Weighing 7 parts by weight of boric acid, edging and bottoming the boric acid on a sample press, and keeping the pressure for 20 seconds at 30 tons.
And (4) sticking a label on the non-measuring surface, and storing the label in a dryer to be measured so as to prevent moisture absorption and pollution.
Repeating the sample preparation step for 5 times to prepare 5 parallel samples, and measuring by a fluorimeter.
The third step: comparison of measurements
The results of the repeatability measurements are shown in table 7:
TABLE 7 repeatability test on Europe gray glass sample
Sample batch number
Se/ppm
180410-1
14.5
180410-2
14.2
180410-3
14
180410-4
13.4
180410-5
13.9
Mean value of
14
Standard deviation S2
0.165
Standard deviation S
0.41
Relative standardDeviation RSD%
2.90
In Table 7, the mean selenium content of the Euro grey glass samples is 14ppm and the relative standard deviation RSD% is 2.9%.
The smaller the relative standard deviation RSD%, the better, generally not more than 5%, meets the measurement requirements.
The repeatability tests of the embodiment 1 and the embodiment 2 are the demonstration of the technical scheme of the invention, and the precision analysis of the repeatability tests shows that the measuring method has good discreteness, high precision, small matrix effect, low detection limit and high result reliability, and can completely meet the production detection requirements. In addition, the method disclosed by the invention is popularized and applied in the daily production monitoring process of the production lines of other subsidiary companies, and has practicability on the color difference control of the soda-lime-silica colored glass.
The above description is only a preferred embodiment of the present invention, and therefore should not be taken as limiting the scope of the invention, which is defined by the appended claims and their equivalents.
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