GB/T 18114.2-2010Chemical analysis method of rare earth concentrates - Part 2: Determination of oxide thorium content (English PDF)

Foreword

GB/T 18114 "Methods for chemical analysis of rare earth concentrates" is divided into 11 parts.

--- Part 1. Determination of total rare earth oxide gravimetric method;

--- Part 2. Determination of thorium oxide content;

--- Part 3. Determination of calcium oxide content;

--- Part 4. niobium oxide, zirconium oxide, titanium oxide content - Inductively coupled plasma atomic emission spectrometry;

--- Part 5. aluminum oxide content - Inductively coupled plasma atomic emission spectrometry;

--- Part 6. Determination of the amount of silica;

--- Part 7. Determination of the amount of iron oxide dichromate method;

--- Part 8. fifteen rare earth element oxide with components measured by inductively coupled plasma atomic emission spectrometry;

--- Part 9. Determination of the amount of phosphorus pentoxide bismuth molybdenum blue spectrophotometric method;

--- Part 10. Determination of moisture content - Gravimetric method;

--- Part 11. Determination of the amount of fluorine EDTA titration. This is Part 2.

This part is GB/T 18114.2-2000 "Methods for chemical analysis of monazite concentrates - Determination of thorium oxide content" amendment.

Section compared with the GB/T 18114.2-2000, major changes in the following.

--- The measurement method for adjusting a plasma emission spectrometry with plasma mass spectrometry by the gravimetric method;

--- The measurement range of 2.00% - 7.00% by the adjustment of 0.0020% - 8.00%.

This part of the National Standardization Technical Committee of rare earth (SAC/TC229) centralized.

This section is Baotou Rare Earth Research Institute, China Nonferrous Metals Industry Institute of Standards Metrology and Quality is responsible for drafting.

Part 1 was drafted by the Ganzhou Nonferrous Metallurgy Research Institute.

Method 1 of this section by the Baotou Rare Earth Research Institute, Inner Mongolia Baotou Steel Rare Earth (Group) Hi-Tech Company participated in the drafting.

1 Scope

GB/T 18114 in the provisions of this part of the determination of thorium oxide content of rare earth concentrates.

This section applies to the determination of rare earth concentrates of thorium oxide content. Method 1 measuring range. 0.0020% to 0.30%; the second measurement method Range. > 0.30% - 8.00%.

Method 1 Inductively Coupled Plasma Mass Spectrometry

2 Principle of the method

Sample with sodium hydroxide - fusion with sodium peroxide decomposition, separation of silicon, aluminum, sodium, with nitric and perchloric damage filter paper and precipitate was dissolved in dilute Acid medium, ionized argon plasma source, direct plasma mass spectrometry, standard method for calibration.

3 Reagents and materials

3.1 Sodium hydroxide.

3.2 Sodium peroxide.

3.3 Nitrate (rho1.42g/mL).

3.4 Perchloric acid (rho1.67g/mL).

3.5 Hydrochloride (11).

3.6 NaOH wash (20g/L).

3.7 Nitrate (1199).

3.8 thoria standard stock solution. Weigh accurately 0.1000g thorium dioxide (w (ThO2) >=99.95%, already at 110 °C drying) to 250mL beaker, was added 10mL of hydrochloric acid (rho1.19g/mL) and 0.5mL of hydrofluoric acid (rho1.14g/mL), dissolved by heating, added 2mL Perchloric acid (3.4) and evaporated to a white smoke shape until wet salt, cooled, dissolved in 5mL hydrochloric acid (3.5) and treated with hydrochloric acid (19) at constant volume 100mL Flask, and mix the solution 1mL containing 1mg thorium dioxide.

3.9 thoria standard solution. Pipette 1.00mL thoria accurate standard stock solution (3.8), in 1000mL volumetric flask. 20mL of nitric acid (11), diluted with water to the mark, and mix the solution 1mL containing 1µg thorium oxide.

3.10 indium standard stock solution. Weigh accurately 1.0000g metal indium (w (In) >=99.9%) in 250mL beaker, add 20mL Hydrochloric acid (3.5), placed on a water bath heated to dissolve, cooled in 1000mL volumetric flask, and mix the solution 1mL 1mg containing indium.

3.11 indium internal standard solution. Pipette 1.00mL indium standard stock solution (3.10) in 1000mL flask, add 100mL nitric acid (3.3), diluted with water to volume, and mix this solution 1mL containing indium 1µg.

3.12 Argon. [w (Ar) >=99.99%].

4 Instrument

Inductively coupled plasma mass spectrometry. mass resolution better than (0.8 ± 0.1) amu.