GB/T 5069-2024 Chemical analysis of magnesia-alumina refractories
Warning: Persons using this document shall be familiar with normal laboratory practice. Persons using this document shall have practical experience in laboratory work and be familiar with the physicochemical properties of strong acids and bases. The high temperatures, strong acids, and strong bases involved in sample preparation are potential hazards. Staff must be well-versed in the relevant safety operating procedures. This document does not purport to address all of the safety problems, if any, associated with its use. It is the responsibility of the user to establish appropriate safety and health measures and to ensure compliance with any national regulatory conditions.
1 Scope
This document describes the chemical analysis methods for magnesia-alumina refractories, including the determination of loss on ignition (LOI), silicon dioxide (SiO2), aluminum oxide (Al2O3), and other parameters.
This document is applicable to magnesia-alumina refractories, such as magnesia (zirconia) bricks, magnesia-alumina (zirconia) bricks, magnesia (alumina) spinel bricks, magnesia-silica bricks, and magnesia-dolomite (zirconia) bricks, as well as raw materials such as magnesia and spinel.
2 Normative references
The following documents contain requirements which, through reference in this text, constitute provisions of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
GB/T 4513.2 Monolithic (unshaped) refractory products - Part 2: Sampling for testing
GB/T 4984 Chemical analysis of refractories containing zirconia
GB/T 5070 Chemical analysis of refractories containing chrome
GB/T 7728 Chemical analysis of metallurgical products - General rule for flame atomic absorption spectrometric methods
GB/T 8170 Rules of rounding off for numerical values & expression and judgment of limiting values
GB/T 10325 Shaped refractory products - Rule of acceptance, sampling and inspection
GB/T 12808 Laboratory glassware - One mark pipettes
GB/T 17617 Rule of sampling and inspection for refractory raw materials
GB/T 18930 Terminology for refractories
GB/T 32179 Chemical analysis of refractories - General requirements for wet chemical analysis, atomic absorption spectrometry (AAS) and inductively coupled plasma atomic emission spectrometry (ICP-AES) methods
3 Terms and definitions
For the purposes of this document, the terms and definitions given in GB/T 18930 apply.
4 Instruments and apparatus
4.1 Balance: With a division of 0.1 mg.
4.2 Platinum or porcelain crucibles: 30 mL.
4.3 Automatic temperature-controlled drying oven: With an operating temperature of 110°C, and a temperature fluctuation limit of ±1.5°C.
4.4 High-temperature furnace: Electric box furnace with a maximum operating temperature greater than or equal to 1,100°C and automatic temperature control.
4.5 Spectrophotometer: With a wavelength of 380–700 nm.
4.6 Thermostatic magnetic stirrer.
4.7 G4 glass funnel.
4.8 Pipette: Class A as specified in GB/T 12808.
4.9 Burette: Class A as specified in GB/T 12805.
4.10 Volumetric flask: Class A as specified in GB/T 12806.
4.11 Atomic absorption spectrometer: Equipped with an air-acetylene burner and hollow cathode lamps for calcium, magnesium, potassium, sodium, and manganese. The purity of the air and acetylene gases shall be no less than 99.9% to provide a stable, clear, lean flame (uniform band-shaped blue-white flame). The “minimum precision requirements”, “characteristic concentration”, “detection limit”, and “linearity (curvature) of the standard curve” shall meet the requirements of GB/T 7728.
4.12 Flame photometer: Capable of measuring K and Na.
Contents Foreword III Introduction IV 1 Scope 2 Normative references 3 Terms and definitions 4 Instruments and apparatus 5 Preparation of specimens 6 General 7 Determination of loss on ignition 8 Determination of silicon dioxide 9 Determination of aluminum oxide 10 Determination of ferric oxide 11 Determination of titanium dioxide 12 Determination of calcium oxide 13 Determination of magnesium oxide 14 Determination of potassium oxide and sodium oxide 15 Determination of manganese oxide [ω(MnO)≤0.5%] 16 Determination of phosphorus pentoxide [ω(P2O5)≤3%] 17 Determination of free calcium oxide in magnesia 18 Determination of zirconium (hafnium) oxide by EDTA volumetric method 19 Determination by ammonium ferrous sulfate volumetric method 20 Determination of silicon dioxide, aluminum oxide, ferric oxide, titanium dioxide, calcium oxide, potassium oxide, sodium oxide, manganese oxide, phosphorus pentoxide, zirconium oxide, and chromium trioxide (inductively coupled plasma atomic emission spectrometry) 21 Test report Annex A (Normative) Acceptance procedures for analysis value Annex B (Informative) Standard curves for inductively coupled plasma-atomic emission spectrograph
