Atomic-absorption spectrophotometry of impurties in alumina for electron ceramic raw materials
Some standard content:
Electronic Industry Standard of the People's Republic of China
Atomic-absorption spectrophotometry of impurities in alumina for electron ceramic raw materials
Atomic-absorption spectrophotometry of impurities in alumina for electron ceramic raw materials Subject content and scope of application
1.1 Subject content
SJ/T10633-1995
Replaces SJ1856-81
This standard specifies the atomic absorption spectrophotometry method for the determination of impurities in alumina for electron ceramic raw materials. 1.2 Scope of application
This standard applies to the determination of calcium, magnesium, iron, potassium and sodium oxides in alumina for electron ceramic raw materials. 2 Reference Standards
Ion absorption spectrophotometric determination of impurities in raw materials of electronic ceramics: clay, feldspar, magnesite, calcite, dolomite, talc, quartz SJ/T10632www.bzxz.net
3 Analytical Methods
3.1 Method I High Pressure Decomposition Method
3.1.1 Summary of Methods
The sample is placed in a closed autoclave and decomposed with hydrochloric acid at 230°C. After keeping warm for 5 minutes, it is cooled naturally. The soluble sample is added with the release agent strontium chloride solution to eliminate the interference of aluminum on calcium and magnesium. Since strontium chloride cannot completely eliminate the interference of aluminum on calcium and magnesium, the same amount of aluminum oxide is added to the standard solution. The absorbance is measured and the result is calculated using the standard curve method. 3.1.2 Reagents
Chloride solution
Calcium carbonate
Magnesium oxide
Iron oxide
Potassium chloride
Sodium chloride
Aluminum oxide powder
Instruments and equipment
36%, 1+1
High purity;
High purity;
High purity:
High purity;
High purity;
Spectrally pure.
Superior pure;
First-class pure;
Approved by the Ministry of Electronics Industry of the People's Republic of China on April 22, 1995 and implemented on October 1, 1995
Autoclave device;
SJ/T10633-1995
Atomic absorption spectrophotometer with wavelength of 200~800nm and resolution of monochromator of 2nm/mm; Sensitivity of analytical balance is 0.1mg, weighing should be accurate to 0.2mg, and range is 200g; High-temperature furnace is above 1000℃;
Oven is 250℃;
Volume flask 100500, 1000ml;
Beaker 100150200ml;
Platinum dish;
Electric hot plate:
Quantity stick;
Alcohol lamp.
Preparation of standard solutions
a. Preparation of single element standard storage solutions
The preparation of calcium oxide, magnesium oxide, iron oxide, potassium oxide and sodium oxide standard solutions shall be carried out according to Article 5.1 of SI1854. Basic aluminum oxide solution:
Weigh two portions of 0.5g aluminum oxide, place them in autoclave reaction cups respectively, add 10ml of 1+1 hydrochloric acid, seal them and place them in an oven, keep them at 230~235C for 5h, cool them naturally, transfer them to a 100ml volumetric flask, add 30ml of concentrated hydrochloric acid to dilute to the scale and shake well, and use them for preparing a series of mixed standard solutions. b. Preparation of mixed standard solution
Pick 5 ml of 1 mg/ml calcium oxide, magnesium oxide, iron oxide and potassium oxide standard solutions, and 50 ml of 1 mg/ml sodium oxide standard solution, and place them in a 500 ml volumetric flask, dilute to scale, shake well, and the concentrations of calcium oxide, magnesium oxide, potassium oxide and iron oxide are all 10 μg/ml, and the concentration of sodium oxide is 100 μg/ml. c. Preparation of mixed standard solution series for determination Take 0, 1, 2.3, 4, 5 ml of the above mixed standard solutions, and place them in a 100 ml volumetric flask, add 10 ml of aluminum oxide basic solution, add 2.5 ml of 30% strontium chloride solution, dilute to scale, and shake well. 3.1.5 Analysis steps
3.1.5.1 Accurately weigh 0.2000g of the sample that has been dried at 110℃ for 2h, place it in a high-pressure reaction cup, add 8ml of 11 hydrochloric acid, seal it and place it in an oven, keep it at 230-235℃ for 5h, cool it naturally, take out the dissolved sample, place it in a 100ml volumetric flask, rinse the reaction cup with water several times, and place it in a volumetric flask, add 2.5ml of 30% strontium chloride solution, and finally dilute to the scale, shake well, and do a blank test at the same time.
3.1.5.2 Adjust the instrument according to the selected instrument working conditions. After the hollow cathode lamp is preheated for 20min, ignite the flame. After normal combustion, adjust the air and acetylene flow rates. Adjust the zero point with water spray, then spray with the standard solution series and the test solution respectively, read the corresponding absorbance, and repeat the measurement with the same solution. The instrument measurement conditions are shown in the table below.
SJ/T10633-1995
Allowed maximum spectral passband
Flame type
Air-acetylene
Note: The current of the hollow cathode lamp is adjusted according to the working current specified when the various lamps leave the factory. 3.1.6 Calculation of analysis results
Flame state
Slightly rich gas flame
Stoichiometric roasting
Draw a standard curve by measuring the average absorbance of the standard solution and the concentration series of the standard solution. According to the difference between the absorbance of the test solution and the blank absorbance, the concentration of the oxide of the element to be tested in the test solution can be directly checked on the curve, and the content of the oxide of each element in the sample can be calculated according to the following formula.
Cx×V×10-6
×100%
Wherein: M is the percentage of the oxide of the element being tested in the sample; Cx is the concentration of the oxide of the element in the sample solution (blank has been deducted), ug/ml: V is the volume of the sample solution, ml;
G is the mass of the sample, g.
3.2 Method II Alkali Fusion Method
3.2.1 Summary of Method
The sample is melted at 1000℃ with a mixed flux of lithium carbonate and boric acid, the melt is leached with hydrochloric acid, and a release agent strontium chloride solution is added to eliminate the interference of aluminum on calcium and magnesium, the absorbance is measured, and the result is calculated using the standard curve method. 3.2.2 Reagents
Lithium carbonate
36%1+1
Spectral pure;
First-grade pure:
Lithium carbonate boric acid mixed flux:
Superior pure:
Grind lithium carbonate and boric acid in an agate mortar in a ratio of 1:1.5 and place in a plastic bottle; e.
Strontium chloride solution
Calcium carbonate
Magnesium oxide
Iron oxide
Potassium oxide
Sodium oxide
High purity;
Aluminum oxide powder
3.2.3 Apparatus and equipment
Same as method I.
3.2.4 Preparation of standard solution
First-grade pure;
Spectral pure.
SJ/T10633-1995
3.2.4.1 The preparation of single element standard storage solution is the same as ao in 3.1.4
Basic alumina solution
Weigh two portions of alumina powder (0.5g), put them in a platinum crucible, add 3g of mixed flux respectively, mix them well, put them in a high-temperature furnace and melt them at 1000℃ for 30min, heat and dissolve them on an electric furnace with 30ml of 1+1 hydrochloric acid, transfer the two solutions into a 250ml volumetric flask, add 40ml of 1+1 hydrochloric acid, dilute to the mark, shake well, and set aside. 3.2.4.2 Preparation of mixed standard solution
Same as b in 3.1.4.
3.2.4.3 Preparation of mixed standard solution series is the same as c in 3.1.4.
3.2.5 Analysis steps
3.2.5.1 Accurately weigh 0.1000g of the sample that has been dried at 110℃ for 2h, place it in a platinum ground, accurately add 0.6g of mixed flux, mix well, put it in a high-temperature furnace and melt it at 1000℃, keep it warm for 30min, add 10ml of 1+1 hydrochloric acid after it cools slightly, heat it on an electric furnace to dissolve the molten block, and after it is completely dissolved, transfer it to a 100ml volumetric flask while it is hot, cool it, add 2.5ml of 30% strontium chloride solution, dilute it to the scale with water, and shake it well. At the same time, perform a blank test. 3.2.5.2 The following steps are the same as those in 3.1.5.2 of Method II. The instrument measurement conditions are the same as those in the instrument measurement conditions table in 3.1.5.2 of Method I. 3.2.6 Calculation of analysis results
The same as 3.1.6 of Method I.
Additional Notes:
This standard is under the jurisdiction of the Standardization Research Institute of the Ministry of Electronics Industry. This standard was drafted by the Standardization Research Institute of the Ministry of Electronics Industry. The main drafters of this standard are: Wang Yugong, Liu Chengjun, Wei Guangyun, Liu Xiulan, and Yu Baoying. 4
Tip: This standard content only shows part of the intercepted content of the complete standard. If you need the complete standard, please go to the top to download the complete standard document for free.