GB/T 6730.68-2009Iron ores - Determination of loss on ignition - Gravimetric method (English PDF)

1 Scope

This Part of GB/T 6730 specifies determination of loss on ignition (LOI) in iron ore by gravimetric method.

This Part is applicable to determination of ignition loss in natural iron ore, iron concentrate and sinter. The determination range (mass fraction): - 10.0%~12.0%.

This Part does not apply to processed minerals containing metallic iron, natural or processed minerals with a sulfur content greater than 0.2% (mass fraction).

2 Normative references

The following referenced documents are indispensable for the application of this part of GB/T 6730. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.

GB/T 6379.2, Measurement methods and results - Accuracy (trueness and precision) - Part 2: Determine the standard methods of measurement repeatability and reproducibility of the basic method (GB/T 6379.2-2004, ISO 5725-2:1994, IDT)

GB/T 6730.1, Iron ores - Preparation of pre-dried test samples for chemical analysis (GB/T 6730.1-1986, idt ISO 7764:1985)

GB/T 8170, Rules of rounding off for numerical values and expression and judgement of limiting values

GB/T 10322.1, Iron ores - Sampling and sample preparation procedures (GB/T 10322.1-2000, idt ISO 3082:1998)

GB/T 20565, Iron ores and direct reduced iron - Vocabulary (GB/T 20565-2006, ISO 11323:2002, IDT)

3 Terms and definitions

The terms and definitions defined in GB/T 20565 apply to this Part.

4 Principle

The test material is ignited to constant weight at 1000°C±25°C. Calculate the ignition loss based on the mass lost.

5 Reagents and materials

Unless otherwise stated, only the confirmed analytically-pure reagents are used in the analysis.

5.1 Silica gel, dried at 105°C for 4h.

6 Equipment

Laboratory routine equipment includes:

6.2 Balance: the sensitivity is 0.1mg.

6.3 High temperature furnace: the maximum operating temperature is not less than 1100°C, and can automatically control the temperature.

6.1 Porcelain crucible or platinum crucible: capacity is 15mL~25mL

7 Sampling and sample preparation