Separation and determination method of coloring metal elements in ultra-white glass

Abstract

The present application belongs to the technical field of glass element content detection, and relates to a method for separating and determining coloring metal elements in ultra-white glass, comprising the following steps: preparing an ultra-white glass sample into a sample solution to be measured, slowly adding an organic ligand sodium hydroxide aqueous solution into the sample solution to be measured, stirring and reacting at room temperature, then filtering the mixed solution after reaction, slowly adding an inorganic acid into the obtained precipitate to continue stirring and reacting, filtering the mixed solution after reaction again, taking the clear solution after solid-liquid separation and transferring it into a volumetric flask, and determining the content of coloring metal elements; the organic ligand has multiple electron-donating groups. The separating and determining method is accurate, simple, fast, and has strong separation selectivity, and the organic ligand can be repeatedly used, thereby providing a reliable, accurate and stable analysis and detection method for analyzing coloring metal elements in ultra-white glass, and facilitating the improvement of the quality of ultra-white glass and the wide use thereof.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of glass element content detection, and relates to a separation and determination method of coloring metal elements in ultra-white glass. BACKGROUND

[0002] Because the ultra-white glass is widely applied in the fields of electronic information and new energy, higher requirements are put forward for various performances of the ultra-white glass, especially in the aspect of transmittance. At present, the iron element is mainly controlled and detected in the production process of the ultra-white glass, and strict requirements are not put forward for other coloring impurities which may affect the transmittance, but the ions which may affect the transmittance of the ultra-white glass also include other transition metal ions (such as Mn, Cr, Cu, Ni, Co and the like) having a vacancy on an orbital and an energy level affected by a coordination field and rare earth ions (such as Ce, Er, Nd and the like) having a vacancy on an f orbital. Therefore, it is also very important to accurately detect the content of these elements and strictly control them in order to improve the transmittance of the ultra-white glass.

[0003] A Chinese invention patent with the publication number CN100370242C discloses a method for simultaneously determining coloring elements in grey glass by using a plasma emission spectrometer. Firstly, the grey glass is subjected to silicon removal treatment by using hydrofluoric acid to reduce the salt content of the test solution, so as to avoid plugging of the torch pipe, increase the cleaning frequency of the torch pipe and reduce the service life of the torch pipe during the on-machine test. The appropriate concentration and acidity of the sample after treatment are determined. The analysis spectral lines adopted in the analysis and determination are Fe wavelength 261.187 nm, Ni wavelength 216.555 nm, Co wavelength 230.786 nm and Se wavelength 196.026 nm. The operation parameters of the instrument are as follows: atomization gas flow 0.75 L / min, auxiliary gas flow 1.5 L / min, radio frequency generator power 0.9 KW, pump speed 15 rpm, plasma 15 L / min, stabilization time 15 s, sample uptake time 30 s and atomizer cleaning time 10 s. The patent method is a test method established for the grey glass. The content of the coloring metal elements in the grey glass is relatively high, and the coloring metal elements can be tested on the inductively coupled plasma emission spectrometer without separation. However, the content of the coloring metal elements in the ultra-white glass is extremely low, and the test method cannot realize accurate analysis and test of the coloring metal elements in the ultra-white glass. Meanwhile, because the composition of the ultra-white glass is complex, the dissolved ultra-white glass sample contains a large amount of alkali metal and alkaline earth metal elements (K, Na, Ca, Mg and the like), which brings difficulty to the analysis and detection of the coloring metal elements. SUMMARY

[0004] In order to overcome the above defects, the present application aims to provide a method for separating and determining coloring metal elements in ultra-white glass.

[0005] In order to achieve the above object, the present application adopts the following technical scheme:

[0006] A method for separating and determining coloring metal elements in ultra-white glass comprises the following steps:

[0007] The ultra-white glass sample is prepared into a sample solution to be measured, and an aqueous sodium hydroxide solution of an organic ligand is slowly added into the sample solution to be measured, and then the mixture is stirred at room temperature, followed by filtering the reacted mixture, slowly adding an inorganic acid into the obtained precipitate, and continuing to stir the mixture, filtering the reacted mixture again, and then transferring the clear solution into a volumetric flask after solid-liquid separation, and determining the content of coloring metal elements; the organic ligand has multiple electron-donating groups.

[0008] Preferably, the preparation method of the organic ligand is as follows: 5-10 mmol of 3-carboxy-salicylaldehyde ethylenediamine is dissolved in 10-20 mL of an organic solvent, 5-10 mmol of 2-hydroxybenzaldehyde is dissolved in 10-20 mL of an organic solvent, the two solutions are mixed, stirred and refluxed for 40-60 min, filtered, washed, and vacuum dried, and then the organic ligand is obtained.

[0009] Preferably, the preparation method of the organic ligand is as follows: 5-10 mmol of N-(2-aminoethyl)-2-salicylamide is dissolved in 10-20 mL of an organic solvent, 5-10 mmol of 3-methoxysalicylaldehyde is dissolved in 10-20 mL of an organic solvent, the two solutions are mixed, stirred and refluxed for 60-80 min, filtered, washed, and vacuum dried, and then the organic ligand is obtained.

[0010] Preferably, the preparation method of the organic ligand is as follows: 5-10 mmol of 3-carboxy-salicylaldehyde ethylenediamine is dissolved in 10-20 mL of an organic solvent, 5-10 mmol of 3-methoxysalicylaldehyde is dissolved in 10-20 mL of an organic solvent, the two solutions are mixed, stirred and refluxed for 40-60 min, filtered, washed, and vacuum dried, and then the organic ligand is obtained.

[0011] Preferably, the preparation method of the sample solution to be measured is as follows:

[0012] 1.5-2.0 g of an ultra-white glass sample is placed in a platinum crucible, wetted with water, and then 2-5 mL of sulfuric acid / perchloric acid, 20-30 mL of hydrofluoric acid are added, and the mixture is heated and treated at 120-160 DEG C for 1-2 h, and then heated and treated at 300-350 DEG C for 2-5 min, and then cooled to room temperature, and then 2-5 mL of nitric acid, 2-5 mL of hydrochloric acid and an appropriate amount of water are added, and the mixture is heated at 70-95 DEG C for 5-10 min, and then cooled to obtain the sample solution to be measured.

[0013] Preferably, the preparation method of the sodium hydroxide aqueous solution of the organic ligand is as follows:

[0014] Dissolve 0.1-0.2 mmol of the organic ligand and 0.3-1.2 mmol of sodium hydroxide in 10-15 mL of water, and stir until dissolved to obtain the sodium hydroxide aqueous solution of the organic ligand.

[0015] Preferably, the inorganic acid is one or more of nitric acid, hydrochloric acid and perchloric acid.

[0016] Preferably, the determination method of the coloring metal element comprises the following steps:

[0017] (1) Preparation of standard curve solutions: respectively take different volumes of Fe, Co, Cu, Ce and Nd single-element standard solutions into 100 mL volumetric flasks to prepare five groups of standard solutions;

[0018] (2) Drawing of standard curve: detect the standard solutions by an inductively coupled plasma emission spectrometer, and draw a standard curve according to the detection results;

[0019] (3) Detecting the sample solution to be measured by the inductively coupled plasma emission spectrometer, and obtaining the content of the coloring metal element according to the standard curve.

[0020] Preferably, the concentrations of the five groups of standard solutions in step (1) are respectively marked as: 1# is a blank solution; 2# contains Fe 0.5 ppm, Co 0.05 ppm, Cu 0.05 ppm, Ce 0.1 ppm and Nd 0.05 ppm; 3# contains Fe 1.0 ppm, Co 0.1 ppm, Cu 0.1 ppm, Ce 0.2 ppm and Nd 0.1 ppm; 4# contains Fe 1.5 ppm, Co 0.15 ppm, Cu 0.15 ppm, Ce 0.3 ppm and Nd 0.15 ppm; and 5# contains Fe 2.0 ppm, Co 0.2 ppm, Cu 0.2 ppm, Ce 0.4 ppm and Nd 0.2 ppm.

[0021] Preferably, the filtered mixed solution after the reaction is subjected to solid-liquid separation, the organic ligand precipitate is collected, the precipitate is washed, the obtained washing solution is transferred into a volumetric flask together with the clarified solution, and the precipitate is dried for reuse.

[0022] In the existing glass test analysis technology, the analysis method for the coloring metal elements contained in the glass composition includes colorimetry, atomic absorption spectrometry and inductively coupled plasma emission spectrometry; the devices used are respectively spectrophotometer, atomic absorption spectrometer and inductively coupled plasma emission spectrometer. Among them, the colorimetry is mainly used for analyzing the iron element with high content in the glass, and has a relatively mature analysis technology, but the application is limited. At the same time, for the color glass with high content of transition metal elements, atomic absorption spectrometry or inductively coupled plasma emission spectrometry is mainly used for detection, and the inductively coupled plasma emission spectrometry can realize the simultaneous determination of multiple elements, while the atomic absorption spectrometry can only realize the determination of one element at a time. Therefore, the inductively coupled plasma emission spectrometry is more and more widely used in glass detection, but when the inductively coupled plasma emission spectrometer is used to analyze the coloring metal elements affecting the transmittance of ultra-white glass in the ultra-white glass, the content of the coloring metal elements in the ultra-white glass is too low to be detected or the detection result signal-to-noise ratio is too low to obtain accurate results. In order to improve the content of the element to be detected, the sample dissolution amount needs to be increased, but this will cause more salt to exist, which will cause greater interference to the determination data, and also will cause the salt accumulation phenomenon of the equipment torch pipe and atomizer due to the high content of salt, and shorten the service life of the equipment consumables. The organic ligand used in the present application can separate the transition metal and rare earth metal affecting the transmittance of glass at the same time, and after being separated from the alkali metal and alkaline earth metal contained in the ultra-white glass, the accurate detection of the trace and trace coloring metal elements contained in the ultra-white glass can be realized on the inductively coupled plasma emission spectrometer, and the content of the coloring metal elements can be strictly controlled in the production process, the transmittance of the ultra-white glass is improved, and the details are as follows:

[0023] 1. In the case that the organic ligand of the present application introduces two nitrogen electron-donating groups by means of ethylenediamine, the ligand I further contains two phenolic hydroxyl groups and one carboxyl group; the ligand II further contains two phenolic hydroxyl groups, one amide group and one methoxyl group; and the ligand III further contains two phenolic hydroxyl groups, one carboxyl group and one methoxyl group. The ligands of the present application all have multiple electron-donating groups, the two nitrogens on the ethylenediamine and the two phenolic hydroxyl groups on the benzene ring together form a planar structure with a certain cavity, which can form a coordination bond with the transition metal, and the presence of the oxygen electron-donating groups on the carboxyl group and the amide group makes the ligand have more binding modes with the coloring ions, which is beneficial to the formation of macromolecular compounds, and the introduction of the carboxyl group and / or the amide group on the benzene ring and the methoxyl group provides sufficient space position for the combination of the rare earth metal and the ligand, so that all the coloring metal elements affecting the transmittance of the ultra-white glass, including the transition metal and the rare earth metal, in the glass sample solution are simultaneously precipitated and separated.

[0024] 2. In the preparation process of the sample solution to be tested, the hydrofluoric acid converts the metal oxides in the sample into water-soluble or acid-soluble salts, and the silicon dioxide in the sample forms silicon tetrafluoride and volatilizes, the sulfuric acid / perchloric acid converts the stable fluorine complex into a salt soluble in hydrochloric acid, and because the boiling point of sulfuric acid / perchloric acid is much higher than that of hydrofluoric acid, the fluorine ions can be completely removed during heating to prevent corrosion of the glass torch tube on the equipment, and other elements in the ultrawhite glass sample except silicon can also be dissolved in sulfuric acid / perchloric acid; the addition of a certain amount of nitric acid provides nitrate as an electron donor to occupy part of the vacancies on the f orbit of rare earth ions, which is conducive to the combination of organic ligands and rare earth ions to form precipitates, and the addition of hydrochloric acid makes the metal elements exist in the form of ions in the sample solution to be tested, and a small amount of water is added to prevent the sample solution from splashing during heating and also to adjust the pH value. The sample solution obtained by the present application can completely dissolve the metal elements in the glass sample and exist in the form of ions in the acidic solution, so that the metal elements can react with the organic ligand.

[0025] 3. In order to prevent the structure of the organic ligand from changing and affecting the combination of the coloring metal elements to form precipitates, the organic ligand is deprotonated in the aqueous solution of sodium hydroxide, and the aqueous solution of sodium hydroxide of the organic ligand is slowly added to the sample solution to be tested when the sample solution is cooled to room temperature, and the reaction is stirred at room temperature, so that the organic ligand can better combine with the transition metal and rare earth metal to form precipitates. Moreover, by adjusting the pH values of the sample solution to be tested and the organic ligand solution, the aqueous solution of sodium hydroxide of the organic ligand is slowly added to the sample solution to be tested, and the reaction is stirred at room temperature for 20-30 min until the precipitates are completely formed, and the pH value of the mixed solution is 3-4, so that the coloring metal elements in the sample solution to be tested can be efficiently separated.

[0026] 4. The coloring metal elements in the sample solution to be tested are precipitated by the aqueous solution of sodium hydroxide of the organic ligand, and after the precipitates formed by the organic ligand and the coloring metal elements are separated from the high-content alkali metal and alkaline earth metal solution in the sample solution to be tested, the precipitates are stirred with one or more of inorganic acids such as nitric acid, hydrochloric acid and perchloric acid at room temperature for 5-10 min, and the coloring metal elements are separated out. Through solid-liquid separation, the inorganic acid solution of the organic ligand and the coloring metal elements is obtained again, and the organic ligand can be repeatedly used without causing environmental pollution due to the discharge of a large amount of organic ligand.

[0027] 5. The precipitate formed by the organic ligand and the coloring metal element is reacted with one or more of the inorganic acids nitric acid, hydrochloric acid and perchloric acid, the coloring metal element is separated out, the coloring metal element is separated completely, the inorganic acid solution of the coloring metal element is detected by an inductively coupled plasma emission spectrometer detection device, the content of the coloring metal element in the ultra-white glass is tested and analyzed quickly, the content of the coloring metal element is detected accurately, simply and quickly, the separation selectivity is strong, a reliable, accurate and stable analysis and detection method for analyzing the coloring metal element in the ultra-white glass is provided, the quality of the ultra-white glass can be improved, and the method can be widely used. BRIEF DESCRIPTION OF DRAWINGS

[0028] Figure 1 The infrared spectrograms of the organic ligands in Examples 1 and 2 are shown in the following figures:

[0029] Figure 2 The infrared spectrograms of the organic ligands in Examples 3 and 4 are shown in the following figures:

[0030] Figure 3 The ultraviolet absorption spectrograms of the organic ligands in Examples 3 and 4 are shown in the following figures:

[0031] Figure 4 The ultraviolet absorption spectrograms of the precipitates formed by the organic ligands in Examples 3 and 4 and the coloring metal element are shown in the following figures:

[0032] Figure 5 The infrared spectrograms of the organic ligands in Examples 5 and 6 are shown in the following figures. DETAILED DESCRIPTION

[0033] The application is further described below in combination with some specific embodiments.

[0034] The reagents involved in the following examples are as follows:

[0035] (1+1) nitric acid refers to a mixed solution of one part of pure nitric acid and one part of water, and the pure nitric acid refers to nitric acid with a weight percentage content of 65-68%;

[0036] (1+4) nitric acid refers to a mixed solution of one part of pure nitric acid and four parts of water, and the pure nitric acid refers to nitric acid with a weight percentage content of 65-68%;

[0037] (1+1) hydrochloric acid refers to a mixed solution of one part of pure hydrochloric acid and one part of water, and the pure hydrochloric acid refers to hydrochloric acid with a weight percentage content of 36-38%;

[0038] (1+4) hydrochloric acid refers to a mixed solution of one part of pure hydrochloric acid and four parts of water, and the pure hydrochloric acid refers to hydrochloric acid with a weight percentage content of 36-38%;

[0039] Perchloric acid refers to perchloric acid with a weight percentage content of 70-72%.

[0040] Example 1

[0041] A method for separating and determining coloring metal elements in ultra-white glass, comprising the following steps:

[0042] Step 1: synthesis of organic ligand I:

[0043] 5 mmol (1.0404 g) of 3-carboxyl salicylaldehyde ethylenediamine was weighed dissolved in 10 mL of methanol, and 5 mmol (0.6102 g) of 2-hydroxybenzaldehyde was weighed dissolved in 10 mL of methanol, the two solutions were mixed, stirred and refluxed for 50 min, filtered, washed and vacuum dried to obtain orange yellow organic ligand [N-(3-carboxyl salicylaldehyde)-N'-(2-hydroxybenzaldehyde) ethylenediamine], and the chemical structural formula is:

[0044]

[0045] The infrared spectrum of the ligand I in this example is shown in Figure 1 From the figure, it can be seen that the vibration absorption peak of ν -1 of the carboxyl group appears near 3287 cm O-H , the vibration absorption peak of ν -1 of the carboxyl group appears at 1661 cm C＝O , the absorption peaks of δ -1 and ν -1 of the phenolic hydroxyl group appear at 1360 cm O-H and 1231 cm C-O respectively, and the vibration absorption peak of ν -1 appears at 1621 cm C＝N , indicating that 3-carboxyl salicylaldehyde ethylenediamine and 2-hydroxybenzaldehyde form an organic ligand with multiple electron-donating groups, which can provide sufficient binding sites for the combination of coloring metals and ligands.

[0046] Step 2: preparation of the sample solution to be tested

[0047] (1) Dissolution of the sample to be tested:

[0048] The ultra-white glass sample was finely ground with a agate mortar, dried in a constant temperature drying oven at 105°C for 1 h, and then cooled to room temperature. 1.5 g of the above ultra-white glass sample was placed in a platinum dish, wetted with water, and then 2 mL of sulfuric acid and 25 mL of hydrofluoric acid were added. The mixture was heated and treated at 120°C on a sand bath for 2 h until white smoke stopped coming out. Then the mixture was heated and treated at 340°C on a high-temperature electric furnace for 5 min to drive out the white smoke, and then cooled to room temperature. Subsequently, 2 mL of (1+1) nitric acid and 5 mL of (1+1) hydrochloric acid and an appropriate amount of water were added, and the mixture was heated and treated at 80°C on a high-temperature electric furnace for 8 min until completely dissolved. The sample solution to be tested was obtained after cooling, and the pH value was 1.

[0049] (2) Preparation of sodium hydroxide aqueous solution of organic ligand:

[0050] Dissolve 0.1 mmol of organic ligand and 0.3 mmol of sodium hydroxide in 10 mL of water, stir until dissolved, to obtain a sodium hydroxide aqueous solution of organic ligand, with a pH value of 7;

[0051] (3) Preparation of sample solution to be tested: slowly add the sodium hydroxide aqueous solution of organic ligand to the sample solution to be tested, stir at room temperature for 20 min until the precipitate is completely obtained, with a pH value of 3, then filter the mixed solution after reaction, slowly add 2 mL (1+4) hydrochloric acid to the obtained precipitate and continue to stir for 5 min, filter the mixed solution after reaction again, after solid-liquid separation, transfer the clear solution to a 100 mL volumetric flask, collect the organic ligand precipitate, wash the precipitate with a small amount of water several times, transfer the obtained washing solution and the clear solution to the volumetric flask, and dilute to 100 mL for determination of the content of coloring metal elements, and the precipitate is dried for repeated use;

[0052] Step 3: Determination of coloring metal elements in the sample, including the following steps:

[0053] (1) Preparation of standard curve solution: respectively take different volumes of Fe, Co, Cu, Ce, Nd single element standard solution with a concentration of 10 ppm to a 100 mL volumetric flask to prepare five groups of standard solutions, see Table 1;

[0054] (2) Drawing of standard curve: detect the standard solutions by inductively coupled plasma emission spectrometer, draw a standard curve according to the detection results, and select Fe 259.940 nm, Co 230.786 nm, Cu 324.754 nm, Ce 418.659 nm, and Nd 406.108 nm as the analysis spectral lines;

[0055] (3) Detect the sample solution to be tested by inductively coupled plasma emission spectrometer, set three groups of samples to be tested, obtain the content of coloring metal elements according to the standard curve, and calculate the average value, and the detection results are shown in Table 2.

[0056] Example 2

[0057] A method for separating and determining coloring metal elements in ultra-white glass, comprising the following steps:

[0058] Step 1: Synthesis of organic ligand: the same as the organic ligand of Example 1;

[0059] Step 2: Preparation of sample solution to be tested

[0060] (1) Dissolution of sample to be tested:

[0061] The super white glass sample is ground with agate mortar, dried in a constant temperature drying oven at 110°C for 1h, and then cooled to room temperature. 2.0g of the super white glass sample is placed in a platinum crucible, wetted with water, and then 5mL of perchloric acid and 25mL of hydrofluoric acid are added. The mixture is heated on a sand bath at 150°C for 2h until white smoke stops coming out. Then the mixture is heated on a high-temperature electric furnace at 300°C for 5min until the white smoke is driven out. The mixture is cooled to room temperature, and then 2mL of (1+1) nitric acid and 3mL of (1+1) hydrochloric acid and an appropriate amount of water are added. The mixture is heated on a high-temperature electric furnace at 90°C for 10min until it is completely dissolved. The mixture is cooled to obtain a sample solution to be tested, and the pH value is 1.5;

[0062] (2) Preparation of sodium hydroxide aqueous solution of organic ligand:

[0063] 0.2mmol of organic ligand and 1.2mmol of sodium hydroxide are dissolved in 15mL of water, and stirred until dissolved to obtain a sodium hydroxide aqueous solution of organic ligand, and the pH value is 7.5;

[0064] (3) Preparation of sample solution to be tested: The sodium hydroxide aqueous solution of organic ligand is slowly added dropwise to the sample solution to be tested, and stirred at room temperature for 30min until the precipitation is complete to obtain a mixed solution, and the pH value is 4. Then the mixed solution after reaction is filtered, and 2mL of (1+4) nitric acid is slowly added dropwise to the obtained precipitate, and stirred for 5min. The mixed solution after reaction is filtered again, and the clear solution is transferred to a 100mL volumetric flask. The organic ligand precipitate is collected, and washed with water for several times. The washing solution and the clear solution are transferred to the volumetric flask, and diluted to 100mL. The content of coloring metal elements is determined, and the precipitate is dried for repeated use.

[0065] Step 3: Determination of coloring metal elements in the sample, including the following steps:

[0066] (1) Preparation of standard curve solution: Different volumes of Fe, Co, Cu, Ce and Nd single-element standard solutions with a concentration of 10ppm are transferred to 100mL volumetric flasks to prepare five groups of standard solutions, which are the same as in Example 1;

[0067] (2) Drawing of standard curve: The standard solutions are detected by inductively coupled plasma emission spectrometer, and the standard curve is drawn according to the detection results. Fe 259.940nm, Co 230.786nm, Cu 324.754nm, Ce 418.659nm and Nd 406.108nm are selected as analysis spectral lines;

[0068] (3) The sample solution to be detected is detected by an inductively coupled plasma emission spectrometer, three groups of the sample to be detected are set, the content of the coloring metal element is obtained according to the standard curve, the average value is calculated, and the detection result is shown in Table 2.

[0069] Example 3

[0070] A method for separating and detecting coloring metal elements in ultra-white glass, comprising the following steps:

[0071] Step 1: Synthesis of organic ligand II:

[0072] 5 mmol (0.9004 g) of N-(2-aminoethyl)-2-salicylamide is weighed and dissolved in 10 mL of methanol, and 5 mmol (0.7602 g) of 3-methoxysalicylaldehyde is weighed and dissolved in 10 mL of methanol, the two solutions are mixed, stirred and refluxed for 60 min, filtered, washed and vacuum dried to obtain yellow organic ligand [N-((2-aminoethyl)-2-salicylamide)-N'-(3-methoxysalicylaldehyde) ethylenediamine], and the chemical structural formula is:

[0073]

[0074] The infrared spectrum of the ligand II in this example is shown in Figure 2 From the figure, it can be seen that the vibration absorption peaks of ν -1 and ν -1 of the amide group appear at 3390 cm N-H and 1648 cm C＝O respectively, the absorption peaks of δ O-H and ν C-O of the phenolic hydroxyl group appear at 1370 cm -1 and 1250 cm -1 respectively, the absorption peak of ν C-O of the methoxy group appears at 1068 cm -1 , and the vibration absorption peak of ν C＝N appears at 1588 cm -1 , indicating that N-(2-aminoethyl)-2-salicylamide and 3-methoxysalicylaldehyde form an organic ligand with multiple electron-donating groups, which can provide sufficient binding sites for the combination of coloring metals and ligands.

[0075] Meanwhile, the ligand is subjected to ultraviolet spectrum analysis, as shown in Figure 3 , the ligand has a weak absorption peak at 400-450 nm due to the existence of π→π* and n→π* electron transitions and the existence of a conjugate, indicating that the ligand contains unsaturated chemical bonds, further indicating the existence of C=N and C=O groups in the ligand.

[0076] Step 2: Preparation of the sample solution to be tested

[0077] (1) Dissolution of the sample to be tested:

[0078] The super white glass sample was ground in a agate mortar and dried in a constant temperature drying oven at 105°C for 1 h, and then cooled to room temperature. 1.5 g of the super white glass sample was placed in a platinum crucible, wetted with water, and then 2 mL of sulfuric acid and 20 mL of hydrofluoric acid were added. The mixture was heated on a sand bath at 140°C for 1.5 h until the white smoke disappeared, and then heated on a high-temperature electric furnace at 340°C for 5 min to drive off the white smoke. The mixture was cooled to room temperature, and then 2 mL of (1+1) nitric acid and 2 mL of (1+1) hydrochloric acid and an appropriate amount of water were added. The mixture was heated on a high-temperature electric furnace at 95°C for 10 min until it was completely dissolved. The solution was cooled to obtain the sample solution to be tested, and the pH value was 1.

[0079] (2) Preparation of the sodium hydroxide aqueous solution of the organic ligand:

[0080] 0.1 mmol of the organic ligand and 0.6 mmol of sodium hydroxide were dissolved in 10 mL of water, and stirred until dissolved to obtain the sodium hydroxide aqueous solution of the organic ligand, and the pH value was 7.

[0081] (3) Preparation of the sample solution to be tested: The sodium hydroxide aqueous solution of the organic ligand was slowly added to the sample solution to be tested, and stirred at room temperature for 30 min until the precipitation was complete to obtain a mixed solution, and the pH value was 3. The mixed solution after reaction was filtered, and 2 mL of (1+4) hydrochloric acid was slowly added to the obtained precipitate and stirred for 10 min. The mixed solution after reaction was filtered again, and after solid-liquid separation, the clear solution was transferred to a 100 mL volumetric flask. The organic ligand precipitate was collected and washed with water for several times. The washing solution and the clear solution were transferred to the volumetric flask together, and the volume was adjusted to 100 mL. The determination of the content of the coloring metal elements was carried out, and the precipitate was dried for repeated use.

[0082] The precipitate obtained by the first separation (i.e. the precipitate formed by the organic ligand and the coloring metal elements) was subjected to ultraviolet spectrum analysis, as shown in Figure 4 compared with Figure 3 , the absorption peak was red-shifted to the long wave direction to about 500-600 nm, the peak shape was obviously broadened, and a small shoulder peak appeared, which was related to the d-d transition of transition metals and f-f transition of rare earth metal ions, indicating that the coloring metal and the electron-donating group on the organic ligand were complexed. The organic ligand can effectively separate the coloring metal ions in the sample solution to be tested.

[0083] Step 3: Determination of the coloring metal elements in the sample, including the following steps:

[0084] (1) Preparation of standard curve solution: different volumes of 10 ppm Fe, Co, Cu, Ce, Nd single element standard solution were taken into 100 mL volumetric flask, respectively, to prepare five groups of standard solution, which was the same as example 1;

[0085] (2) Preparation of standard curve: the standard solution was detected by inductively coupled plasma emission spectrometer, and the standard curve was drawn according to the detection results, and Fe 259.940 nm, Co 230.786 nm, Cu 324.754 nm, Ce 418.659 nm and Nd 406.108 nm were selected as analysis spectral lines;

[0086] (3) The sample solution to be detected was detected by inductively coupled plasma emission spectrometer, and three groups of samples to be detected were set, and the content of coloring metal elements was obtained according to the standard curve, and the average value was calculated, and the detection results were shown in table 2.

[0087] Example 4

[0088] A method for separating and determining coloring metal elements in ultra-white glass, comprising the following steps:

[0089] Step 1: synthesis of organic ligand: the same as the organic ligand in example 3.

[0090] Step 2: preparation of sample solution to be detected

[0091] (1) Dissolution of sample to be detected:

[0092] The ultra-white glass sample was finely ground with agate mortar, dried in a constant temperature drying oven at 110 DEG C for 1 h, and then cooled to room temperature. 1.5 g of the above ultra-white glass sample was placed in a platinum dish, wetted with water, and then 3 mL of perchloric acid and 30 mL of hydrofluoric acid were added. It was heated and treated on a sand bath at 140 DEG C for 2 h, until the white smoke disappeared. Then it was heated and treated on a high temperature electric furnace at 300 DEG C for 3 min, and the white smoke was driven off. After cooling to room temperature, 5 mL of (1+1) nitric acid and 3 mL of (1+1) hydrochloric acid and appropriate amount of water were added, and heated and treated on a high temperature electric furnace at 70 DEG C for 5 min. After heating to complete dissolution, the sample solution to be detected was obtained, and the pH value was 1;

[0093] (2) Preparation of sodium hydroxide aqueous solution of organic ligand:

[0094] 0.1 mmol of organic ligand and 1.2 mmol of sodium hydroxide were dissolved in 10 mL of water, and stirred until dissolved to obtain a sodium hydroxide aqueous solution of organic ligand with a pH value of 7.5;

[0095] (3) Preparation of the sample solution to be measured: slowly add the sodium hydroxide aqueous solution of the organic ligand to the sample solution to be measured, stir the reaction at room temperature for 30 min until the precipitation is complete, obtain a mixed solution with a pH value of 3.5, then filter the mixed solution after the reaction, slowly add 2 mL of perchloric acid to the obtained precipitate and continue to stir the reaction for 10 min, filter the mixed solution after the reaction again, after solid-liquid separation, transfer the clear solution to a 100 mL volumetric flask, collect the organic ligand precipitate, wash the precipitate with water for several times, transfer the obtained washing solution and the clear solution to the volumetric flask, and then dilute to 100 mL, and then determine the content of the coloring metal elements, and then dry the precipitate for repeated use;

[0096] Step 3: determination of the coloring metal elements in the sample, including the following steps:

[0097] (1) Preparation of the standard curve solution: respectively take different volumes of Fe, Co, Cu, Ce and Nd single-element standard solutions with a concentration of 10 ppm to 100 mL volumetric flasks to prepare five groups of standard solutions, which are the same as those in Example 1;

[0098] (2) Drawing of the standard curve: detect the standard solutions by using an inductively coupled plasma emission spectrometer, draw a standard curve according to the detection results, and select Fe 259.940 nm, Co 230.786 nm, Cu 324.754 nm, Ce 418.659 nm and Nd 406.108 nm as the analysis spectral lines;

[0099] (3) Detection of the sample solution to be measured by using an inductively coupled plasma emission spectrometer, three groups of sample solutions to be measured are set, the content of the coloring metal elements is obtained according to the standard curve, and the average value is calculated, and the detection results are shown in Table 2.

[0100] Example 5

[0101] A method for separating and determining the coloring metal elements in ultra-white glass, including the following steps:

[0102] Step 1: synthesis of the organic ligand III:

[0103] Take 5 mmol (1.0404 g) of 3-carboxy-salicylaldehyde ethylenediamine dissolved in 10 mL of methanol, and take 5 mmol (0.7602 g) of 3-methoxysalicylaldehyde dissolved in 10 mL of methanol, mix the two solutions, stir and reflux for 50 min, filter, wash and vacuum dry to obtain a yellow organic ligand [N-(3-carboxy-salicylaldehyde ethylenediamine)-N'-(3-methoxysalicylaldehyde) ethylenediamine];

[0104]

[0105] The infrared spectrum of the ligand III of this embodiment is shown in Figure 5 From the figure, it can be seen that the vibration absorption peak of the carboxyl group appears near 2937 cm -1 The vibration absorption peak of the carboxyl group appears at 1633 cm O-H The vibration absorption peak of the carboxyl group appears at 1633 cm -1 The vibration absorption peak of the carboxyl group appears at 1633 cm C＝O The vibration absorption peak of the carboxyl group appears at 1633 cm -1 The vibration absorption peak of the carboxyl group appears at 1633 cm -1 The vibration absorption peak of the carboxyl group appears at 1633 cm O-H The vibration absorption peak of the carboxyl group appears at 1633 cm C-O The vibration absorption peak of the carboxyl group appears at 1633 cm -1 The vibration absorption peak of the carboxyl group appears at 1633 cm C-O The vibration absorption peak of the carboxyl group appears at 1633 cm -1 The vibration absorption peak of the carboxyl group appears at 1633 cm C＝N The vibration absorption peak of the carboxyl group appears at 1633 cm

[0106] Step 2: Preparation of the sample solution to be tested

[0107] (1) Dissolution of the sample to be tested:

[0108] The ultra-white glass sample is finely ground in a marquis mortar, dried in a constant temperature drying oven at 100°C for 1 h, and then cooled to room temperature. 1.5 g of the above ultra-white glass sample is placed in a platinum dish, wetted with water, and then 2 mL of sulfuric acid and 25 mL of hydrofluoric acid are added. The sample is heated and treated on a sand bath at 160°C for 1 h until white smoke stops coming out. Then the sample is heated and treated at 300°C on a high-temperature electric furnace for 5 min to drive out the white smoke, and then cooled to room temperature. Next, 2 mL of (1+1) nitric acid and 2 mL of (1+1) hydrochloric acid and an appropriate amount of water are added, and the sample is heated and treated at 80°C on a high-temperature electric furnace for 8 min until it is completely dissolved. The sample solution to be tested is obtained after cooling, and the pH value is 1.5;

[0109] (2) Preparation of the sodium hydroxide aqueous solution of the organic ligand:

[0110] 0.1 mmol of the organic ligand and 0.4 mmol of sodium hydroxide are dissolved in 10 mL of water, and stirred until dissolved to obtain the sodium hydroxide aqueous solution of the organic ligand, and the pH value is 7;

[0111] (3) Preparation of the sample solution to be measured: slowly add the sodium hydroxide aqueous solution of the organic ligand to the sample solution to be measured, stir the reaction at room temperature for 25 min until the precipitation is complete, obtain a mixed solution with a pH value of 3, then filter the mixed solution after the reaction, slowly add 2 mL (1+4) hydrochloric acid to the obtained precipitate and continue to stir for 5 min, filter the mixed solution after the reaction again, after solid-liquid separation, transfer the clear solution to a 100 mL volumetric flask, collect the organic ligand precipitate, wash the precipitate with a small amount of water for several times, transfer the obtained washing solution to the volumetric flask together with the clear solution, and dilute to 100 mL for determination of the content of the coloring metal elements, and the precipitate is dried for repeated use;

[0112] Step 3: determination of the coloring metal elements in the sample, including the following steps:

[0113] (1) Preparation of the standard curve solution: respectively take different volumes of Fe, Co, Cu, Ce and Nd single-element standard solutions with a concentration of 10 ppm to 100 mL volumetric flasks to prepare five groups of standard solutions, which are the same as in Example 1;

[0114] (2) Drawing of the standard curve: detect the standard solutions by an inductively coupled plasma emission spectrometer, draw a standard curve according to the detection results, and select Fe 259.940 nm, Co 230.786 nm, Cu 324.754 nm, Ce 418.659 nm and Nd 406.108 nm as the analysis spectral lines;

[0115] (3) Detection of the sample solution to be measured by the inductively coupled plasma emission spectrometer, three groups of sample solutions to be measured are set, the content of the coloring metal elements is obtained according to the standard curve, and the average value is calculated, and the detection results are shown in Table 2.

[0116] Example 6

[0117] A method for separating and determining the coloring metal elements in ultra-white glass, including the following steps:

[0118] Step 1: synthesis of the organic ligand: the same as the organic ligand in Example 5;

[0119] Step 2: preparation of the sample solution to be measured

[0120] (1) Dissolution of the sample to be measured:

[0121] The super white glass sample is ground in a agate mortar, dried in a constant temperature drying oven at 110°C for 1h, then cooled to room temperature, 2.0g of the above super white glass sample is placed in a platinum crucible, wetted with water, then 3mL of perchloric acid and 30mL of hydrofluoric acid are added, heated and treated on a sand bath at 130°C for 2h until the white smoke disappears, then heated and treated on a high temperature furnace at 350°C for 2min, the white smoke is driven off, and then cooled to room temperature, followed by the addition of 2mL of (1+1) nitric acid and 2mL of (1+1) hydrochloric acid and an appropriate amount of water, heated and treated on a high temperature furnace at 90°C for 10min until completely dissolved, and then cooled to obtain the sample solution to be tested, with a pH value of 2;

[0122] (2) Preparation of sodium hydroxide aqueous solution of organic ligand:

[0123] 0.2mmol of organic ligand and 1.2mmol of sodium hydroxide are dissolved in 10mL of water, stirred until dissolved to obtain the sodium hydroxide aqueous solution of organic ligand, with a pH value of 8;

[0124] (3) Preparation of sample solution to be tested: The sodium hydroxide aqueous solution of organic ligand is slowly added to the sample solution to be tested, stirred at room temperature for 30min until the precipitate is completely formed, to obtain a mixed solution with a pH value of 3.5, then the mixed solution after reaction is filtered, 2mL of (1+4) nitric acid is slowly added to the obtained precipitate and stirred for 5min, the mixed solution after reaction is filtered again, after solid-liquid separation, the clear solution is transferred to a 100mL volumetric flask, the organic ligand precipitate is collected and washed with water for several times, the obtained washing solution is transferred to the volumetric flask together with the clear solution, and then diluted to 100mL for determination of the content of coloring metal elements, and the precipitate is dried for repeated use;

[0125] Step 3: Determination of coloring metal elements in the sample, including the following steps:

[0126] (1) Preparation of standard curve solution: different volumes of Fe, Co, Cu, Ce and Nd single element standard solutions with a concentration of 10ppm are transferred to 100mL volumetric flasks respectively to prepare five groups of standard solutions, which are the same as in Example 1;

[0127] (2) Drawing of standard curve: the standard solutions are detected by inductively coupled plasma atomic emission spectrometer, and the standard curve is drawn according to the detection results, and Fe 259.940nm, Co 230.786nm, Cu 324.754nm, Ce 418.659nm and Nd 406.108nm are selected as analysis spectral lines;

[0128] (3) using inductively coupled plasma emission spectrometer to detect the sample solution to be tested, the sample to be tested is set in three groups, according to the standard curve, the content of the coloring metal element is obtained, the average value is calculated, and the detection result is shown in table 2.

[0129] Table 1 five groups of standard solution

[0130]

[0131] Table 2 content detection result of coloring metal element

[0132] Ingredients (wt. %) Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Fe 0.00946 0.00951 0.00956 0.00957 0.00939 0.00943 Co 0.00093 0.00096 0.00094 0.00095 0.00093 0.00099 Cu 0.00089 0.00090 0.00090 0.00092 0.00091 0.00088 Ce 0.00116 0.00113 0.00122 0.00122 0.00115 0.00125 Nd 0.00069 0.00070 0.00072 0.00075 0.00074 0.00068

[0133] From table 2, in the tested ultra-white glass sample, except that the content of iron is slightly high, the content of other coloring metal elements is extremely low, if the sample solution is calculated according to the normal test and analysis of glass industry, when the constant volume is 100ml, the higher content of Fe in the sample solution to be tested is 0.5ppm, the content of Ce is 0.06ppm, the content of Co and Cu is less than 0.05ppm, and the content of Nd in the sample solution to be tested is as low as 0.03ppm, the elements with such low content in the solution are difficult to obtain accurate and stable test data by using inductively coupled plasma emission spectrometer, and in the case of increasing the sample amount, the coloring metal elements to be detected are separated from a large amount of alkali metal and alkaline earth metal elements in the glass body by using organic ligand, so that stable and accurate detection data can be obtained for the ultra-white glass sample with extremely low content of coloring metal elements.

[0134] Verification experiment

[0135] Accurately weigh 3 portions of 1.5g standard ultra-white glass sample (except that Fe2O3 does not contain other coloring metal elements) in a platinum crucible, sample number A, B, C, respectively, add water to wet, add 2ml of sulfuric acid and 20ml of hydrofluoric acid, heat and treat on a sand bath at 140℃ for 1.5h, until white smoke is exhausted, then continue to heat and treat at 340℃ on a high temperature electric furnace for 5min, drive away white smoke, cool to room temperature, then add 2ml of (1+1) nitric acid, 2ml of (1+1) hydrochloric acid and appropriate amount of water, continue to heat at 95℃ on a high temperature electric furnace for 10min, heat and dissolve sufficiently, cool, add a certain amount of Co, Cu, Ce, Nd single element standard solution with a concentration of 100ppm to the above solution respectively, to obtain verification sample solution.

[0136] Then, according to the preparation steps of the sample solution to be tested in step 2 of example 3, the sodium hydroxide aqueous solution of the organic ligand is slowly added to the verification sample solution for separation experiment, the steps are not repeated, the obtained clear solution is constant volume to 100ml volumetric flask, and the detection is carried out according to the method for determining the coloring metal element in the sample in step 3 of example 3, and the determination result is shown in table 3.

[0137] Table 3 recovery experiment test results

[0138]

[0139]

[0140] From Table 3, it can be seen that the recovery rate of each element is between 92% and 100% through the separation determination of the standard ultra-white glass sample with known coloring element content, which can meet the analysis requirement, and it is proved that the separation determination method is feasible.

[0141] Finally, it should be pointed out that the above examples are only used to illustrate the technical solutions of the present application but not limit the present application, and other modifications or equivalent replacements to the technical solutions of the present application made by those skilled in the art should be covered in the scope of the claims of the present application as long as they do not deviate from the spirit and scope of the present application.

Claims

1. A method for the separate determination of coloring metal elements in an ultra-white glass, characterized by, It comprises the following steps: The ultra-white glass sample is prepared into a sample solution to be tested, and an aqueous sodium hydroxide solution of an organic ligand is slowly added into the sample solution to be tested, and the reaction is stirred at room temperature, then the mixed solution after the reaction is filtered, and an inorganic acid is slowly added into the obtained precipitate to continue the stirring reaction, the mixed solution after the reaction is filtered again, and after the solid-liquid separation, the clear solution is transferred into a volumetric flask to determine the content of coloring metal elements; the organic ligand has multiple electron-donating groups; The preparation method of the organic ligand is as follows: 5-10 mmol of 3-carboxy salicylaldehyde ethylenediamine is dissolved in 10-20 mL of an organic solvent, 5-10 mmol of 2-hydroxybenzaldehyde is dissolved in 10-20 mL of an organic solvent, the two solutions are mixed, stirred and refluxed for 40-60 min, filtered, washed and vacuum dried to obtain the organic ligand; Or the preparation method of the organic ligand is as follows: 5-10 mmol of N-(2-aminoethyl)-2-salicylamide is dissolved in 10-20 mL of an organic solvent, 5-10 mmol of 3-methoxysalicylaldehyde is dissolved in 10-20 mL of an organic solvent, the two solutions are mixed, stirred and refluxed for 60-80 min, filtered, washed and vacuum dried to obtain the organic ligand; Or the preparation method of the organic ligand is as follows: 5-10 mmol of 3-carboxy salicylaldehyde ethylenediamine is dissolved in 10-20 mL of an organic solvent, 5-10 mmol of 3-methoxysalicylaldehyde is dissolved in 10-20 mL of an organic solvent, the two solutions are mixed, stirred and refluxed for 40-60 min, filtered, washed and vacuum dried to obtain the organic ligand.

2. The method of claim 1, wherein the colored metal elements in the ultra-white glass are separated and determined. The preparation method of the sample solution to be tested is as follows: 1.5-2.0 g of an ultra-white glass sample is placed in a platinum crucible, wetted with water, then 2-5 mL of sulfuric acid / perchloric acid, 20-30 mL of hydrofluoric acid are added, heated and treated at 120-160℃ for 1-2 h, then heated and treated at 300-350℃ for 2-5 min, cooled to room temperature, then 2-5 mL of nitric acid, 2-5 mL of hydrochloric acid and an appropriate amount of water are added, heated at 70-95℃ for 5-10 min, and cooled to obtain the sample solution to be tested.

3. The method of claim 2, wherein the colored metal elements in the ultra-white glass are separated and determined. The preparation method of the aqueous sodium hydroxide solution of the organic ligand is as follows: 0.1-0.2 mmol of the organic ligand and 0.3-1.2 mmol of sodium hydroxide are dissolved in 10-15 mL of water, and stirred until dissolved to obtain the aqueous sodium hydroxide solution of the organic ligand.

4. The method of claim 1, wherein the colored metal elements in the ultra-white glass are separated and determined. The inorganic acid is one or more of nitric acid, hydrochloric acid and perchloric acid.

5. The method of claim 1, wherein the colored metal elements in the ultra-white glass are separated and determined. The determination method of the coloring metal elements comprises the following steps: (1) Preparation of a standard curve solution: different volumes of Fe, Co, Cu, Ce and Nd single-element standard solutions are respectively taken into 100 mL volumetric flasks to prepare five groups of standard solutions; (2) Drawing of a standard curve: the standard solutions are detected by an inductively coupled plasma emission spectrometer, and a standard curve is drawn according to the detection results; (3) The sample solution to be tested is detected by the inductively coupled plasma emission spectrometer, and the content of coloring metal elements is obtained according to the standard curve.

6. The method of claim 5, wherein the colored metal elements in the ultra-white glass are separated and determined. The concentrations of the five groups of standard solutions in step (1) are respectively marked as: 1# is blank solution; 2# contains Fe0.5ppm, Co0.05ppm, Cu0.05ppm, Ce0.1ppm, Nd0.05ppm; 3# contains Fe1.0ppm, Co0.1ppm, Cu0.1ppm, Ce0.2ppm, Nd0.1ppm; 4# contains Fe1.5ppm, Co0.15ppm, Cu0.15ppm, Ce0.3ppm, Nd0.15ppm; 5# contains Fe2.0ppm, Co0.2ppm, Cu0.2ppm, Ce0.4ppm, Nd0.2ppm.

7. The method of claim 5, wherein the colored metal elements in the ultra-white glass are separated and determined. The filtered mixed solution after the reaction is again filtered, and the organic ligand precipitate is collected after solid-liquid separation, and the precipitate is washed. The washing solution is transferred into a volumetric flask together with the clear solution, and the precipitate is dried for reuse.

Images