{"id":3991,"date":"2025-10-10T16:30:51","date_gmt":"2025-10-10T08:30:51","guid":{"rendered":"https:\/\/www.pgeneral.com\/?p=3991"},"modified":"2025-10-10T16:30:51","modified_gmt":"2025-10-10T08:30:51","slug":"determination-of-iron-in-graphite-powder-flame-atomic-absorption-spectrometry","status":"publish","type":"post","link":"https:\/\/www.pgeneral.com\/ru\/applications\/determination-of-iron-in-graphite-powder-flame-atomic-absorption-spectrometry\/","title":{"rendered":"\u041e\u043f\u0440\u0435\u0434\u0435\u043b\u0435\u043d\u0438\u0435 \u0441\u043e\u0434\u0435\u0440\u0436\u0430\u043d\u0438\u044f \u0436\u0435\u043b\u0435\u0437\u0430 \u0432 \u043f\u043e\u0440\u043e\u0448\u043a\u0435 \u0433\u0440\u0430\u0444\u0438\u0442\u0430 (\u0441\u043f\u0435\u043a\u0442\u0440\u043e\u043c\u0435\u0442\u0440\u0438\u044f \u0430\u0442\u043e\u043c\u043d\u043e\u0439 \u0430\u0431\u0441\u043e\u0440\u0431\u0446\u0438\u0438 \u043f\u043b\u0430\u043c\u0435\u043d\u0438)"},"content":{"rendered":"

1. Method Overview<\/h2>\n
After the sample is digested with aqua regia, the determination is carried out using an air-acetylene flame at an instrument wavelength of 248.3 nm.<\/div>\n
\n

2. Instruments and Reagents<\/h2>\n

2.1 Instruments and Equipment<\/h3>\n

2.1.1 Testing Instruments<\/h4>\n
\n
\n\n\n\n\n\n\n\n
Serial No.<\/th>\nName<\/th>\nQuantity<\/th>\nTechnical Requirements<\/th>\nAccessories<\/th>\n<\/tr>\n<\/thead>\n
1<\/td>\nFlame Atomic Absorption Spectrophotometer<\/td>\n1 set<\/td>\n–<\/td>\nIron Hollow Cathode Lamp<\/td>\n<\/tr>\n
2<\/td>\nAcetylene Gas<\/td>\n1 cylinder<\/td>\nPurity \u2265 99.99%<\/td>\n–<\/td>\n<\/tr>\n
3<\/td>\nAir Compressor<\/td>\n1 set<\/td>\nRated discharge pressure: 0.3 MPa<\/td>\n–<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<\/div>\n

2.1.2 Sample Pretreatment Equipment<\/h4>\n
\n
\n\n\n\n\n\n\n\n\n\n\n
Serial No.<\/th>\nName<\/th>\nQuantity<\/th>\nTechnical Requirements<\/th>\nAccessories<\/th>\n<\/tr>\n<\/thead>\n
1<\/td>\nTemperature-Controlled Hot Plate<\/td>\n1 set<\/td>\nRated temperature range: Room temperature ~ 300 \u2103<\/td>\n–<\/td>\n<\/tr>\n
2<\/td>\nElectronic Balance<\/td>\n1 set<\/td>\nSensitivity: 0.1 mg<\/td>\n–<\/td>\n<\/tr>\n
3<\/td>\nUltrapure Water System<\/td>\n1 set<\/td>\n–<\/td>\n–<\/td>\n<\/tr>\n
4<\/td>\nMicropipette<\/td>\n1 each<\/td>\nRanges: 20 \u03bcL ~ 200 \u03bcL, 100 \u03bcL ~ 1000 \u03bcL<\/td>\n–<\/td>\n<\/tr>\n
5<\/td>\nVolumetric Flask<\/td>\nSeveral<\/td>\nVolume: 100 mL<\/td>\n–<\/td>\n<\/tr>\n
6<\/td>\nTest Tube<\/td>\nSeveral<\/td>\nVolume: 25 mL<\/td>\n–<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<\/div>\n

2.2 Reagents<\/h3>\n

2.2.1 Raw Reagents<\/h4>\n
\n
\n\n\n\n\n\n\n
Serial No.<\/th>\nName<\/th>\nTechnical Requirements<\/th>\nRemarks<\/th>\n<\/tr>\n<\/thead>\n
1<\/td>\nNitric Acid<\/td>\nMOS Grade<\/td>\n–<\/td>\n<\/tr>\n
2<\/td>\nHydrochloric Acid<\/td>\nGuaranteed Reagent (GR)<\/td>\n–<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<\/div>\n

2.2.2 Prepared Reagents<\/h4>\n
\n
\n\n\n\n\n\n
Serial No.<\/th>\nName<\/th>\nPreparation Method<\/th>\nRemarks<\/th>\n<\/tr>\n<\/thead>\n
1<\/td>\n(1+99) Nitric Acid Solution<\/td>\nMeasure 10 mL of nitric acid, slowly add it to 990 mL of deionized water, and mix well.<\/td>\n–<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<\/div>\n

2.3 Reference Standards<\/h3>\n

2.3.1 Stock Solution<\/h4>\n
\n
\n\n\n\n\n\n
Serial No.<\/th>\nNo.<\/th>\nName<\/th>\nTechnical Requirements<\/th>\nRemarks<\/th>\n<\/tr>\n<\/thead>\n
1<\/td>\nGBW08616<\/td>\nIron Single-Element Standard Substance Solution<\/td>\nConcentration: 1000 \u03bcg\/mL<\/td>\nProvided by National Institute of Metrology, China<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<\/div>\n

3. Operational Procedures<\/h2>\n

3.1 Sample Preparation<\/h3>\n

3.1.1 Preparation of Test Solution<\/h4>\n
Weigh 0.25 g of the sample (accurate to 0.00001 g) into a digestion tank. Add 3 mL of concentrated nitric acid and 9 mL of concentrated hydrochloric acid, cover and tighten the digestion tank, then place it in a microwave digestion system for digestion. Prepare a blank sample using the same method. After cooling, filter the solution and dilute it to the marked volume in a 25 mL volumetric flask. The solution is ready for on-machine testing.<\/div>\n
<\/div>\n
Microwave Heating Program<\/strong><\/div>\n
<\/div>\n
\n
\n\n\n\n\n\n\n\n\n\n
Step<\/th>\nTemperature (\u2103)<\/th>\nHolding Time (min)<\/th>\n<\/tr>\n<\/thead>\n
1<\/td>\n100<\/td>\n3<\/td>\n<\/tr>\n
2<\/td>\n120<\/td>\n3<\/td>\n<\/tr>\n
3<\/td>\n140<\/td>\n3<\/td>\n<\/tr>\n
4<\/td>\n160<\/td>\n3<\/td>\n<\/tr>\n
5<\/td>\n180<\/td>\n30<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<\/div>\n

3.1.2 Preparation of Standard Solutions<\/h4>\n
    \n
  1. Preparation of Iron Standard Series\n
    <\/div>\n

    Accurately pipette 0.0, 0.05, 0.1, 0.2, and 0.3 mL of the iron standard solution (1000 \u03bcg\/mL) into separate 100 mL volumetric flasks respectively. Add 5 mL of strontium chloride solution to each flask, then dilute to the marked volume with (1+99) nitric acid solution and mix well. The concentrations of this standard series are 0.0, 0.5, 1.0, 2.0, and 3.0 \u03bcg\/mL.<\/li>\n<\/ol>\n

    3.2 Sample Testing<\/h3>\n
      \n
    1. Testing Conditions\n
      <\/div>\n

      Reference Conditions for Flame Atomic Absorption Spectrophotometer<\/strong><\/li>\n<\/ol>\n

      <\/div>\n
      \n
      \n\n\n\n\n\n\n\n\n\n\n\n\n
      Parameter<\/th>\nSpecification<\/th>\n<\/tr>\n<\/thead>\n
      Element<\/td>\nIron<\/td>\n<\/tr>\n
      Wavelength (nm)<\/td>\n(To be specified based on instrument calibration)<\/td>\n<\/tr>\n
      Spectral Bandwidth (nm)<\/td>\n(To be specified based on instrument calibration)<\/td>\n<\/tr>\n
      Element Lamp Current (mA)<\/td>\n3.0<\/td>\n<\/tr>\n
      Fuel Height (mm)<\/td>\n6<\/td>\n<\/tr>\n
      Fuel Flow Rate (mL\/min)<\/td>\n1400<\/td>\n<\/tr>\n
      Air Compressor Pressure (MPa)<\/td>\n0.22<\/td>\n<\/tr>\n
      Background Correction Method<\/td>\nNone<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<\/div>\n
      <\/div>\n
        \n
      1. Sample Testing\n
        <\/div>\n

        Adjust the instrument to its optimal working state, ignite the flame and adjust the fuel flow rate. Test the standard solutions and sample solutions in sequence, read the data, input the sample weight, then check and record the results.<\/li>\n<\/ol>\n<\/div>\n