1 Scope
This standard specifies the general method for the determination of residue after ignition by gravimetric method.
This standard is applicable to the determination of residue after ignition with chemical reagent which can sublimate or carbonize and remove the subject at 650℃ ± 50℃. When the ignition residue is determined by this standard, the residue mass calculated according to the sampling amount and specification value shall not be less than 1mg.
2 Principle of method
Through utilizing the differences in physical and chemical properties such as volatility, stability to heat and oxygen between the bulk sample and residue substance, the sample is heated at low temperature to be volatilized and carbonized, and subjected to ignite high-temperature ignition, so that the bulk sample is completely separated from the residue, and finally the residue mass is weighted by a balance.
3 Apparatus
3.1 General laboratory apparatus.
3.2 Crucible or evaporating dish: the material may be platinum, quartz or ceramics according to the characteristics of the sample.
3.3 High-temperature furnace: the temperature may be controlled at 650℃ ± 50℃.
3.4 Analytical balance: with a division of 0.1mg.
Foreword I
1 Scope
2 Principle of method
3 Apparatus
4 Determination
5 Calculations
