Method for detecting gallium, germanium and indium in high-temperature vitreous furnace slag

Abstract

The invention relates to the technical field of metal detection, in particular to a method for detecting gallium, germanium and indium in high-temperature vitreous furnace slag, which comprises the following steps: drying and grinding the high-temperature vitreous furnace slag, mixing with an alkali solvent, melting at high temperature, cooling, adding water, and filtering to obtain a precipitate containing gallium, germanium and indium; soaking and dissolving the precipitate with dilute acid, and then carrying out microwave digestion; and after digestion is completed, adding a boric acid solution to neutralize residual hydrofluoric acid, and detecting by adopting inductively coupled plasma mass spectrometry after volume metering. According to the present invention, the alkali melting is combined with the microwave digestion, such that the complete dissolution of the sample is achieved, the matrix interference is reduced, and the detection sensitivity and the detection accuracy are improved. The method has the advantages of short pretreatment time, safe operation, wide application range and the like, and can effectively solve the problems of complex sample pretreatment, low detection sensitivity and serious matrix interference in the prior art.

Description

Technical Field

[0001] The present invention relates to the technical field of metal detection, in particular to a method for detecting gallium, germanium and indium in high-temperature glassy slag. Background Art

[0002] High-temperature vitreous slag, a byproduct of metallurgical processes, often contains rare metal elements such as gallium (Ga), germanium (Ge), and indium (In). These elements are of great industrial value, but their concentrations are low and their distribution is uneven. Traditional detection methods suffer from the following issues: complex sample pretreatment, making complete dissolution difficult; insufficient detection sensitivity, making it difficult to accurately determine low-content elements; and significant matrix interference, which affects the accuracy of test results. To address these issues, we propose a method for the detection of gallium, germanium, and indium in high-temperature vitreous slag. Summary of the Invention

[0003] The purpose of the present invention is to provide a method for detecting gallium, germanium and indium in high-temperature glassy slag, so as to solve the problems of complex sample pretreatment, low detection sensitivity and serious matrix interference in the prior art.

[0004] To achieve the above object, the present invention provides the following technical solutions:

[0005] A method for detecting gallium, germanium, and indium in high-temperature glassy slag comprises the following steps:

[0006] Step 1: drying the high-temperature vitreous slag and then grinding it to obtain high-temperature vitreous slag powder;

[0007] Step 2: Weigh a certain amount of high-temperature glass slag powder and mix it with an excess of alkali flux, melt it at high temperature, and add deionized water to the melt after cooling to obtain a suspension. Then, add sodium sulfide to the suspension, first adjust the pH to 4-6, and then adjust the pH to 2-3. After sufficient stirring, filter and obtain a precipitate containing gallium, germanium, and indium;

[0008] Step 3: transferring the precipitate containing gallium, germanium, and indium into a microwave digestion tank, adding excess dilute acid, stirring thoroughly, and soaking, and then performing microwave digestion;

[0009] Step 4: After cooling, transfer the microwave digestion solution to a colorimetric tube, add the internal standard solution, and adjust the volume with deionized water to obtain a test solution;

[0010] Step 5: Using inductively coupled plasma mass spectrometry to detect the test liquid.

[0011] Preferably, in step 1, drying the high-temperature glass slag includes:

[0012] Evenly spread the high-temperature vitreous slag on a high-temperature resistant tray with a thickness not exceeding 2 cm;

[0013] Place the high temperature resistant tray in an electric blast oven, the drying temperature is 105℃~110℃, and the drying time is 2~6 hours.

[0014] Preferably, in step 1, the ground high-temperature vitreous slag is passed through a 200-mesh sieve to obtain high-temperature vitreous slag powder.

[0015] Preferably, in step 2, the alkali flux is any one of sodium hydroxide, sodium carbonate, and sodium peroxide, and the process specifically comprises the following steps:

[0016] Mixing high-temperature glassy slag powder with an excess amount of alkali flux, wherein the mass ratio of the alkali flux to the high-temperature glassy slag powder is 5 to 10:1;

[0017] High temperature melting, melting temperature is 900℃~1200℃, melting time is 15~30 minutes;

[0018] After cooling, deionized water is added to the melt to obtain a suspension;

[0019] Sodium sulfide is added to the suspension in a mass ratio of sodium sulfide to high-temperature vitreous slag powder of 1:10-20. After sufficient stirring, the suspension is filtered, and the precipitate is washed several times with deionized water to obtain a precipitate containing gallium, germanium, and indium.

[0020] Preferably, in step 3, the dilute acid is dilute HNO3, the concentration of the dilute acid is 4 to 8 mol / L, the amount of dilute acid added is 5 to 10 times the mass of the sample, HF is also added to the dilute acid, the volume ratio of HF to dilute acid is 1:10 to 20, and the soaking time is 2 to 4 hours.

[0021] Preferably, in step 3, the temperature control program of microwave digestion specifically includes the following stages:

[0022] Stage 1: heating rate 10℃ / min, heating to 100℃, holding time 5 minutes;

[0023] Stage 2: heating rate 10℃ / min, heating to 150℃, holding time 10 minutes;

[0024] Stage 3: heating rate 10℃ / min, heating to 200℃, holding time 20 minutes;

[0025] Stage 4: heating rate 5°C / min, heating to 220°C, holding time 15 minutes;

[0026] Stage 5: Cooling rate 20℃ / min, cooling to room temperature.

[0027] Preferably, in step 3, after microwave digestion is completed and cooled to room temperature, a boric acid solution with a mass fraction of 5% to 10% is added to the digestion solution, and the volume ratio of the boric acid solution to the added HF is 3 to 5:1.

[0028] Preferably, in step 4, the microwave digestion solution is transferred to a 50 mL colorimetric tube after cooling, and the internal standard element is yttrium (Y) or rhodium (Rh).

[0029] Preferably, in step 5, the measurement parameters of the inductively coupled plasma mass spectrometry are: RF power of 1300-1500 W, carrier gas flow rate of 0.8-1.2 L / min, cooling gas flow rate of 12-16 L / min, dwell time of 10-50 ms, and scan number of 10-20 times.

[0030] Preferably, in step 5, the detection of the test liquid by inductively coupled plasma mass spectrometry includes the following steps:

[0031] Prepare a series of standard solutions containing target elements gallium, germanium, and indium, with concentrations covering the expected concentrations of the target elements in the sample;

[0032] Determine the standard solution and establish a calibration curve;

[0033] Measure the blank solution to prevent the standard solution from interfering with the test solution;

[0034] Determine the test solution and calculate the content of the target element in the test solution using the internal standard method based on the calibration curve and the signal intensity of the test solution.

[0035] Compared with the prior art, the present invention has the following beneficial effects:

[0036] 1. This method for detecting gallium, germanium, and indium in high-temperature vitreous slag combines alkali melting with microwave digestion and staged programmed temperature increase, effectively dissolving gallium, germanium, and indium in high-temperature vitreous slag, ensuring the full release of target elements in the sample and avoiding the problem of incomplete sample dissolution in traditional methods.

[0037] 2. The detection method of gallium, germanium and indium in high-temperature glassy slag adopts microwave digestion technology, which significantly shortens the sample pretreatment time, can complete the sample digestion process in a shorter time, and improves the detection efficiency.

[0038] 3. This method for detecting gallium, germanium, and indium in high-temperature glassy slag effectively reduces matrix interference and improves detection accuracy and reliability by neutralizing residual hydrofluoric acid with boric acid after microwave digestion.

[0039] 4. The method for detecting gallium, germanium and indium in high-temperature vitreous slag uses inductively coupled plasma mass spectrometry (ICP-MS), which has high sensitivity and low detection limit. It can accurately determine low levels of gallium, germanium and indium in high-temperature vitreous slag, meeting the needs of trace element detection.

[0040] 5. This method for detecting gallium, germanium, and indium in high-temperature glassy slag uses an internal standard method for quantitative analysis, which reduces the influence of instrument fluctuations and matrix effects on the test results and ensures the accuracy and repeatability of the test results.

[0041] 6. In this method for detecting gallium, germanium, and indium in high-temperature glassy slag, boric acid solution is added after microwave digestion to neutralize residual hydrofluoric acid, thereby avoiding the harm of hydrofluoric acid to instruments and experimenters and improving the safety of operation. DETAILED DESCRIPTION

[0042] The following is a clear and complete description of the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of the present invention.

[0043] The present invention provides a technical solution:

[0044] A method for detecting gallium, germanium, and indium in high-temperature glassy slag comprises the following steps:

[0045] Step 1: Dry the high-temperature glass slag and then grind it to obtain high-temperature glass slag powder.

[0046] Preferably, drying the high-temperature glass slag comprises:

[0047] Evenly spread the high-temperature vitreous slag on a high-temperature resistant tray with a thickness not exceeding 2 cm;

[0048] Place the high temperature resistant tray in an electric blast oven, the drying temperature is 105℃~110℃, and the drying time is 2~6 hours.

[0049] In addition, the ground high-temperature vitreous slag is passed through a 200-mesh sieve to obtain high-temperature vitreous slag powder.

[0050] The evenly distributed high-temperature glass slag powder is obtained through step 1, which is convenient for subsequent reaction operations.

[0051] Step 2: Weigh a certain amount of high-temperature glass slag powder and mix it with an excess of alkali flux, melt it at high temperature, and add deionized water to the melt after cooling to obtain a suspension. Then, add sodium sulfide to the suspension, first adjust the pH to 4-6, and then adjust the pH to 2-3. After sufficient stirring, filter and obtain a precipitate containing gallium, germanium, and indium;

[0052] Preferably, the alkali flux is any one of sodium hydroxide, sodium carbonate, and sodium peroxide, and the process specifically comprises the following steps:

[0053] Mixing high-temperature glassy slag powder with an excess amount of alkali flux, wherein the mass ratio of the alkali flux to the high-temperature glassy slag powder is 5 to 10:1;

[0054] High temperature melting, melting temperature is 900℃~1200℃, melting time is 15~30 minutes;

[0055] After cooling, deionized water is added to the melt to obtain a suspension;

[0056] Sodium sulfide is added to the suspension, with a mass ratio of sodium sulfide to high-temperature vitreous slag powder of 1:10-20. The pH is first adjusted to 4-6, and then to 2-3. After sufficient stirring, the suspension is filtered, and the precipitate is washed several times with deionized water to obtain a precipitate containing gallium, germanium, and indium.

[0057] First, the alkali is melted, and then sodium sulfide is added. The pH is first adjusted to 4-6, and sodium gallate, sodium indiumate and sodium sulfide react to form a precipitate. Then the pH is adjusted to 2-3, and sodium germanate reacts with sodium sulfide to form a germanium sulfide precipitate. After filtration, a precipitate containing gallium, germanium and indium is obtained. All salts in the suspension are removed by filtration in the aqueous phase to avoid damage to the instrument during subsequent measurements. The precipitate is washed with deionized water to remove unreacted sodium sulfide in the precipitate.

[0058] Step 3: Transfer the precipitate containing gallium, germanium and indium into a microwave digestion tank, add excess dilute acid, stir thoroughly and soak, and then perform microwave digestion.

[0059] Preferably, the dilute acid is dilute HNO3, the concentration of the dilute acid is 4-8 mol / L, the amount of dilute acid added is 5-10 times the mass of the sample, HF is also added to the dilute acid, the volume ratio of HF to dilute acid is 1:10-20, and the soaking time is 2-4 hours.

[0060] Preferably, the temperature control program of microwave digestion specifically includes the following stages:

[0061] Stage 1: heating rate 10℃ / min, heating to 100℃, holding time 5 minutes;

[0062] Stage 2: heating rate 10℃ / min, heating to 150℃, holding time 10 minutes;

[0063] Stage 3: heating rate 10℃ / min, heating to 200℃, holding time 20 minutes;

[0064] Stage 4: heating rate 5°C / min, heating to 220°C, holding time 15 minutes;

[0065] Stage 5: Cooling rate 20℃ / min, cooling to room temperature.

[0066] In this step, the gallium, germanium and indium are converted into soluble ions (Ga 3+ 、Ge 4+ 、In 3+ ), and further promote the dissolution of gallium, germanium, and indium by adding HF to the dilute acid. Then, microwave digestion is continued to fully extract gallium, germanium, and indium from the high-temperature glassy slag, fully dissolving gallium, germanium, and indium to improve the accuracy of detection. In addition, the microwave digestion selects programmed temperature increase to gradually digest the different components in the sample at the optimal temperature, improving digestion efficiency and avoiding volatilization of target elements. Complete digestion of the sample is achieved in a short time, ensuring the accuracy of the test results.

[0067] In addition, after microwave digestion is completed and cooled to room temperature, a boric acid solution with a mass fraction of 5% to 10% needs to be added to the digestion solution, and the volume ratio of the boric acid solution to the added HF is 3 to 5:1.

[0068] Hydrofluoric acid is highly corrosive and toxic to the human body. Residual HF will corrode glass and quartz instrument components. Boric acid is added to neutralize the residual HF and prevent it from harming the instrument and experimenters.

[0069] Step 4: After cooling, transfer the microwave digestion solution to a colorimetric tube, add the internal standard solution, and adjust the volume with deionized water to obtain the test solution.

[0070] Preferably, after cooling, the microwave digestion solution is transferred to a 50 mL colorimetric tube, and the internal standard element is yttrium (Y) or rhodium (Rh).

[0071] Step 5: Using inductively coupled plasma mass spectrometry to detect the test liquid.

[0072] Preferably, the measurement parameters of the inductively coupled plasma mass spectrometry are: radio frequency power of 1300-1500 W, carrier gas flow rate of 0.8-1.2 L / min, cooling gas flow rate of 12-16 L / min, dwell time of 10-50 ms, and scan number of 10-20 times.

[0073] The detection of the test liquid by inductively coupled plasma mass spectrometry includes the following steps:

[0074] Prepare a series of standard solutions containing target elements gallium, germanium, and indium, with concentrations covering the expected concentrations of the target elements in the sample;

[0075] Determine the standard solution and establish a calibration curve;

[0076] Measure the blank solution to prevent the standard solution from interfering with the test solution;

[0077] Determine the test solution and calculate the content of the target element in the test solution using the internal standard method based on the calibration curve and the signal intensity of the test solution.

[0078] Now, the following will be described in detail with reference to Examples 1 to 3 and Comparative Examples 1 to 5:

[0079] The high-temperature vitreous slag produced in the same batch was evenly spread on a high-temperature resistant tray with a thickness not exceeding 2 cm, and the high-temperature resistant tray was placed in an electric blast oven with a drying temperature of 110°C and a drying time of 4 hours. The ground high-temperature vitreous slag was sieved through a 200-mesh sieve to obtain high-temperature vitreous slag powder, which was used as the experimental raw material for the detection operations of the following Examples 1 to 3 and Comparative Examples 1 to 5.

[0080] Example 1

[0081] 0.5000 g of high-temperature vitreous slag powder was weighed and mixed with an excess of sodium hydroxide, the mass ratio of sodium hydroxide to high-temperature vitreous slag powder being 5:1, and the mixture was melted at a high temperature of 900°C for 30 minutes. After cooling, deionized water was added to the melt to obtain a suspension, and then sodium sulfide was added to the suspension, the mass ratio of sodium sulfide to high-temperature vitreous slag powder being 1:10. The pH was first adjusted to 4, and then to 2. After sufficient stirring, the mixture was filtered, and the precipitate was washed several times with deionized water to obtain a precipitate containing gallium, germanium, and indium.

[0082] The precipitate containing gallium, germanium, and indium was transferred to a microwave digestion tank and added with 4 mol / L HNO3, stirred thoroughly, and then soaked. The amount of dilute acid added was 10 times the mass of the sample, and HF was added to the dilute HNO3 with a volume ratio of HF to dilute HNO3 of 1:10. The soaking time was 4 hours, and then microwave digestion was carried out. The temperature control program of microwave digestion specifically includes the following stages:

[0083] Stage 1: heating rate 10℃ / min, heating to 100℃, holding time 5 minutes;

[0084] Stage 2: heating rate 10℃ / min, heating to 150℃, holding time 10 minutes;

[0085] Stage 3: heating rate 10℃ / min, heating to 200℃, holding time 20 minutes;

[0086] Stage 4: heating rate 5°C / min, heating to 220°C, holding time 15 minutes;

[0087] Stage 5: Cooling rate 20℃ / min, cooling to room temperature.

[0088] After the digestion was completed and cooled to room temperature, a 5% by mass boric acid solution was added to the digestion solution, and the volume ratio of the boric acid solution to the added HF was 5:1.

[0089] After cooling, the microwave digestion solution was transferred to a 50 mL colorimetric tube, and an internal standard solution of yttrium (Y) was added, and the volume was adjusted with deionized water. After the volume was adjusted, the internal standard concentration was 10 μg / L to obtain the test solution.

[0090] The test liquid was detected by inductively coupled plasma mass spectrometry.

[0091] The measurement parameters of the inductively coupled plasma mass spectrometry were as follows: radio frequency power of 1300 W, carrier gas flow rate of 0.8 L / min, cooling gas flow rate of 12 L / min, dwell time of 10 ms, and scan number of 10 times.

[0092] The detection of the test liquid by inductively coupled plasma mass spectrometry includes the following steps:

[0093] Prepare a series of standard solutions containing the target elements gallium, germanium, and indium with concentrations of 0.1 μg / L, 0.5 μg / L, 1 μg / L, 5 μg / L, 10 μg / L, 20 μg / L, 50 μg / L, and 100 μg / L, respectively, and add yttrium (Y) as an internal standard solution to each solution so that the internal standard concentration is 10 μg / L.

[0094] Determine the standard solution and establish a calibration curve;

[0095] Measure the blank solution to prevent the standard solution from interfering with the test solution;

[0096] Determine the test solution and calculate the content of the target element in the test solution using the internal standard method based on the calibration curve and the signal intensity of the test solution.

[0097] Example 2

[0098] 0.5000 g of high-temperature vitreous slag powder was weighed and mixed with an excess of sodium carbonate, the mass ratio of sodium carbonate to high-temperature vitreous slag powder being 8:1, and the mixture was melted at a high temperature of 1000° C. for 25 minutes. After cooling, deionized water was added to the melt to obtain a suspension, and then sodium sulfide was added to the suspension, the mass ratio of sodium sulfide to high-temperature vitreous slag powder being 1:15. The pH was first adjusted to 5 and then to 2. After sufficient stirring, the mixture was filtered, and the precipitate was washed several times with deionized water to obtain a precipitate containing gallium, germanium, and indium.

[0099] The precipitate containing gallium, germanium, and indium was transferred to a microwave digestion tank and added with 6 mol / L HNO3, stirred thoroughly, and then soaked. The amount of dilute acid added was 8 times the mass of the sample. HF was added to the dilute HNO3, and the volume ratio of HF to dilute HNO3 was 1:15. The soaking time was 3 hours, and then microwave digestion was carried out. The temperature control program of microwave digestion specifically includes the following stages:

[0100] Stage 1: heating rate 10℃ / min, heating to 100℃, holding time 5 minutes;

[0101] Stage 2: heating rate 10℃ / min, heating to 150℃, holding time 10 minutes;

[0102] Stage 3: heating rate 10℃ / min, heating to 200℃, holding time 20 minutes;

[0103] Stage 4: heating rate 5°C / min, heating to 220°C, holding time 15 minutes;

[0104] Stage 5: Cooling rate 20℃ / min, cooling to room temperature.

[0105] After the digestion was completed and cooled to room temperature, a boric acid solution with a mass fraction of 8% was added to the digestion solution, and the volume ratio of the boric acid solution to the added HF was 4:1.

[0106] After cooling, the microwave digestion solution was transferred to a 50 mL colorimetric tube, and an internal standard solution of yttrium (Y) was added, and the volume was adjusted with deionized water. After the volume was adjusted, the internal standard concentration was 10 μg / L to obtain the test solution.

[0107] The test liquid was detected by inductively coupled plasma mass spectrometry.

[0108] The measurement parameters of the inductively coupled plasma mass spectrometry were as follows: radio frequency power of 1400 W, carrier gas flow rate of 1.0 L / min, cooling gas flow rate of 14 L / min, dwell time of 30 ms, and scan number of 15 times.

[0109] The detection of the test liquid by inductively coupled plasma mass spectrometry includes the following steps:

[0110] Prepare a series of standard solutions containing the target elements gallium, germanium, and indium with concentrations of 0.1 μg / L, 0.5 μg / L, 1 μg / L, 5 μg / L, 10 μg / L, 20 μg / L, 50 μg / L, and 100 μg / L, respectively, and add yttrium (Y) as an internal standard solution to each solution so that the internal standard concentration is 10 μg / L.

[0111] Determine the standard solution and establish a calibration curve;

[0112] Measure the blank solution to prevent the standard solution from interfering with the test solution;

[0113] Determine the test solution and calculate the content of the target element in the test solution using the internal standard method based on the calibration curve and the signal intensity of the test solution.

[0114] Example 3

[0115] 0.4998 g of high-temperature vitreous slag powder was weighed and mixed with an excess of sodium peroxide, with a mass ratio of sodium peroxide to high-temperature vitreous slag powder of 10:1. The mixture was melted at a high temperature of 1200°C for 15 minutes. After cooling, deionized water was added to the melt to obtain a suspension. Sodium sulfide was then added to the suspension, with a mass ratio of sodium sulfide to high-temperature vitreous slag powder of 1:20. The pH was first adjusted to 6 and then to 3. The mixture was thoroughly stirred and filtered. The precipitate was washed several times with deionized water to obtain a precipitate containing gallium, germanium, and indium.

[0116] The precipitate containing gallium, germanium, and indium was transferred to a microwave digestion tank, and HNO3 with a concentration of 8 mol / L was added and stirred thoroughly before soaking. The amount of dilute acid added was 5 times the mass of the sample, and HF was added to the dilute HNO3 with a volume ratio of HF to dilute HNO3 of 1:20. The soaking time was 2 hours, and then microwave digestion was carried out. The temperature control program of microwave digestion specifically includes the following stages:

[0117] Stage 1: heating rate 10℃ / min, heating to 100℃, holding time 5 minutes;

[0118] Stage 2: heating rate 10℃ / min, heating to 150℃, holding time 10 minutes;

[0119] Stage 3: heating rate 10℃ / min, heating to 200℃, holding time 20 minutes;

[0120] Stage 4: heating rate 5°C / min, heating to 220°C, holding time 15 minutes;

[0121] Stage 5: Cooling rate 20℃ / min, cooling to room temperature.

[0122] After the digestion was completed and cooled to room temperature, a 10% by mass boric acid solution was added to the digestion solution, and the volume ratio of the boric acid solution to the added HF was 3:1.

[0123] After cooling, the microwave digestion solution was transferred to a 50 mL colorimetric tube, and internal standard solution rhodium (Rh) was added and the volume was adjusted with deionized water. After adjustment, the internal standard concentration was 10 μg / L to obtain the test solution.

[0124] The test liquid was detected by inductively coupled plasma mass spectrometry.

[0125] The measurement parameters of the inductively coupled plasma mass spectrometry were as follows: radio frequency power of 1500 W, carrier gas flow rate of 1.2 L / min, cooling gas flow rate of 16 L / min, dwell time of 50 ms, and scan number of 20 times.

[0126] The detection of the test liquid by inductively coupled plasma mass spectrometry includes the following steps:

[0127] Prepare a series of standard solutions containing the target elements gallium, germanium, and indium with concentrations of 0.1 μg / L, 0.5 μg / L, 1 μg / L, 5 μg / L, 10 μg / L, 20 μg / L, 50 μg / L, and 100 μg / L, respectively, and add rhodium (Rh) as an internal standard solution to each solution so that the internal standard concentration is 10 μg / L.

[0128] Determine the standard solution and establish a calibration curve;

[0129] Measure the blank solution to prevent the standard solution from interfering with the test solution;

[0130] Determine the test solution and calculate the content of the target element in the test solution using the internal standard method based on the calibration curve and the signal intensity of the test solution.

[0131] The test results of Examples 1 to 3 are listed in the following table:

[0132]

[0133] Example 4

[0134] Detection limit determination

[0135] Using diatomaceous earth instead of the sample, 0.005 μg of gallium, germanium, and indium standard solutions were added to 0.5000 g of diatomaceous earth, and the measurement was performed according to the same steps as in Example 1. The above operation was repeated 7 times, and the measurement results are as follows:

[0136]

[0137] According to the calculation formula of detection limit:

[0138] MDL=t (n-1,0.99)×S

[0139] Where: MDL is the method detection limit;

[0140] n is the number of parallel measurements of the sample;

[0141] t is the t distribution (one-sided) with n-1 degrees of freedom and 99% confidence level;

[0142] S is the standard deviation of n replicate measurements.

[0143] After calculation, the detection limit of gallium is MDL = 3.143 × 0.00116 = 0.0036 mg / kg

[0144] The detection limit of germanium is MDL = 3.143 × 0.00115 = 0.0036 mg / kg

[0145] The detection limit of indium is MDL = 3.143 × 0.00197 = 0.0062 mg / kg

[0146] The lower limits of determination for gallium, germanium, and indium are 0.014 mg / kg, 0.014 mg / kg, and 0.025 mg / kg, respectively.

[0147] Example 5

[0148] Precision determination

[0149] The same steps as in Example 1 were followed to determine the concentrations of 0.1 mg / kg and 2 mg / kg, respectively. Each concentration was repeated 6 times. The results are as follows:

[0150]

[0151] The relative standard deviations of gallium, germanium and indium are all less than 10%, and the precision meets the measurement requirements.

[0152] Example 6

[0153] Recovery determination

[0154] The same steps as in Example 1 were followed to determine the concentrations of 0.05 mg / kg, 0.5 mg / kg, and 5 mg / kg, respectively. Each concentration was repeated three times. The results are as follows:

[0155]

[0156] The recovery rates of gallium, germanium and indium are between 80% and 104%, and the accuracy meets the measurement requirements.

[0157] Comparative Example 1

[0158] The difference from Example 1 is that the high-temperature vitreous slag powder is not subjected to alkali melting, and 0.5000 g of the high-temperature vitreous slag powder is directly weighed into a microwave digestion tank. The subsequent operations are exactly the same as in Example 1.

[0159] Comparative Example 2

[0160] 0.5000 g of high-temperature vitreous slag powder was weighed and mixed with an excess of sodium hydroxide, the mass ratio of sodium hydroxide to high-temperature vitreous slag powder being 1:1, and the mixture was melted at a high temperature of 900° C. for 30 minutes. After cooling, deionized water was added to the melt to obtain a suspension, and then sodium sulfide was added to the suspension, the mass ratio of sodium sulfide to high-temperature vitreous slag powder being 1:10. The pH was first adjusted to 4, and then to 2. After sufficient stirring, the mixture was filtered, and the precipitate was washed several times with deionized water to obtain a precipitate containing gallium, germanium, and indium.

[0161] The difference from Example 1 is that the precipitate containing gallium, germanium and indium is transferred to a microwave digestion tank, and then 4 mol / L HNO3 (10 times the mass of the sample) is added, and HF is added to the dilute HNO3, with a volume ratio of HF to dilute HNO3 of 1:10, and direct microwave digestion is performed. The subsequent operations are exactly the same as in Example 1.

[0162] Comparative Example 3

[0163] The difference from Example 1 is that the microwave digestion is to directly increase the temperature to 220° C. at a heating rate of 10° C. / min and hold for 15 minutes. The other steps are exactly the same as in Example 1.

[0164] Comparative Example 4

[0165] The difference from Example 1 is that 0.5000 g of high-temperature vitreous slag powder was weighed into a microwave digestion tank, and then 4 mol / L HNO3 (10 times the mass of the sample) was added, and HF was added to the dilute HNO3, with a volume ratio of HF to dilute HNO3 of 1:10. Direct microwave digestion was performed, and the subsequent operations were exactly the same as in Example 1.

[0166] The test results of Comparative Examples 1 to 4 are listed in the following table:

[0167]

[0168] By comparing the above test results, the detection method of the present technical solution has complete sample dissolution, short pretreatment time, reduced matrix interference, high sensitivity and more accurate detection results.

[0169] The above shows and describes the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions are merely preferred examples of the present invention and are not intended to limit the present invention. Various changes and improvements may be made to the present invention without departing from the spirit and scope of the present invention. Such changes and improvements fall within the scope of the present invention. The scope of protection claimed in the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for detecting gallium, germanium and indium in high-temperature glassy slag, characterized in that: The following steps are involved: Step 1: drying the high-temperature vitreous slag and then grinding it to obtain high-temperature vitreous slag powder; Step 2: Weigh a certain amount of high-temperature glass slag powder and mix it with an excess of alkali flux, melt it at high temperature, and add deionized water to the melt after cooling to obtain a suspension. Then, add sodium sulfide to the suspension, first adjust the pH to 4-6, and then adjust the pH to 2-3. After sufficient stirring, filter and obtain a precipitate containing gallium, germanium, and indium; Step 3: transferring the precipitate containing gallium, germanium, and indium into a microwave digestion tank, adding excess dilute acid, stirring thoroughly, and soaking, and then performing microwave digestion; Step 4: After cooling, transfer the microwave digestion solution to a colorimetric tube, add the internal standard solution, and adjust the volume with deionized water to obtain a test solution; Step 5: Using inductively coupled plasma mass spectrometry to detect the test liquid.

2. The method for detecting gallium, germanium and indium in high-temperature glassy slag according to claim 1, characterized in that: In the step 1, drying the high-temperature glass slag includes: Evenly spread the high-temperature vitreous slag on a high-temperature resistant tray with a thickness not exceeding 2 cm; Place the high temperature resistant tray in an electric blast oven, the drying temperature is 105℃~110℃, and the drying time is 2~6 hours.

3. The method for detecting gallium, germanium and indium in high-temperature glassy slag according to claim 1, characterized in that: In the step 1, the ground high-temperature vitreous slag is passed through a 200-mesh sieve to obtain high-temperature vitreous slag powder.

4. The method for detecting gallium, germanium and indium in high-temperature glassy slag according to claim 1, characterized in that: In the step 2, the alkali flux is any one of sodium hydroxide, sodium carbonate, and sodium peroxide, and specifically comprises the following steps: Mixing high-temperature glassy slag powder with an excess amount of alkali flux, wherein the mass ratio of the alkali flux to the high-temperature glassy slag powder is 5 to 10:1; High temperature melting, melting temperature is 900℃~1200℃, melting time is 15~30 minutes; After cooling, deionized water is added to the melt to obtain a suspension; Sodium sulfide is added to the suspension in a mass ratio of sodium sulfide to high-temperature vitreous slag powder of 1:10-20. After sufficient stirring, the suspension is filtered, and the precipitate is washed several times with deionized water to obtain a precipitate containing gallium, germanium, and indium.

5. The method for detecting gallium, germanium and indium in high-temperature glassy slag according to claim 1, characterized in that: In step 3, the dilute acid is dilute HNO3, the concentration of the dilute acid is 4-8 mol / L, the amount of the dilute acid added is 5-10 times the mass of the sample, HF is also added to the dilute acid, the volume ratio of HF to the dilute acid is 1:10-20, and the soaking time is 2-4 hours.

6. The method for detecting gallium, germanium and indium in high-temperature glassy slag according to claim 5, characterized in that: In step 3, the temperature control program of microwave digestion specifically includes the following stages: Stage 1: heating rate 10℃ / min, heating to 100℃, holding time 5 minutes; Stage 2: heating rate 10℃ / min, heating to 150℃, holding time 10 minutes; Stage 3: heating rate 10℃ / min, heating to 200℃, holding time 20 minutes; Stage 4: heating rate 5°C / min, heating to 220°C, holding time 15 minutes; Stage 5: Cooling rate 20℃ / min, cooling to room temperature.

7. The method for detecting gallium, germanium and indium in high-temperature glassy slag according to claim 6, characterized in that: In step 3, after microwave digestion is completed and the solution is cooled to room temperature, a boric acid solution with a mass fraction of 5% to 10% is added to the digestion solution, and the volume ratio of the boric acid solution to the added HF is 3 to 5:

1.

8. The method for detecting gallium, germanium and indium in high-temperature glassy slag according to claim 7, characterized in that: In the step 4, after cooling, the microwave digestion solution is transferred to a 50 mL colorimetric tube, and the internal standard element is yttrium (Y) or rhodium (Rh).

9. The method for detecting gallium, germanium and indium in high-temperature glassy slag according to claim 1, characterized in that: In step 5, the measurement parameters of the inductively coupled plasma mass spectrometry are: radio frequency power of 1300-1500 W, carrier gas flow rate of 0.8-1.2 L / min, cooling gas flow rate of 12-16 L / min, dwell time of 10-50 ms, and scan number of 10-20 times.

10. The method for detecting gallium, germanium and indium in high-temperature glassy slag according to claim 1, characterized in that: In step 5, the detection of the test liquid by inductively coupled plasma mass spectrometry includes the following steps: Prepare a series of standard solutions containing target elements gallium, germanium, and indium, with concentrations covering the expected concentrations of the target elements in the sample; Determine the standard solution and establish a calibration curve; Measure the blank solution to prevent the standard solution from interfering with the test solution; Determine the test solution and calculate the content of the target element in the test solution using the internal standard method based on the calibration curve and the signal intensity of the test solution.

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