GB/T 8576-2010Determination of free water for compound fertilizers - Vacuum oven method (English PDF)

Foreword

This Standard is one of the series standards for the test methods of compound fertilizers, these series of national standards are listed as follows.

-- GB/T 8571-2008 Preparation of Laboratory Samples for Compound Fertilizers;

-- GB/T 8572-2010 Determination of Total Nitrogen Content for Compound Fertilizers Titrimetric Method after Distillation;

-- GB/T 8573-2010 Determination of Available Phosphorus Content for Compound Fertilizers;

-- GB/T 8574-2010 Determination of Potassium Content for Compound Fertilizers - Potassium Tetraphenylborate Gravimetric Method;

-- GB/T 8576-2010 Determination of Free Water for Compound Fertilizers - Vacuum Oven Method;

-- GB/T 8577-2010 Determination of Free Water for Compound Fertilizers - Karl Fischer Method;

-- GB/T 24890-2010 Determination of Chloride Content for Compound Fertilizers;

-- GB/T 24891-2010 Determination of Particle Size for Compound Fertilizers.

This Standard replaces GB/T 8576-2002 Determination of Free Water for Compound Fertilizers - Vacuum Oven Method.

The major differences between this Standard and previous editions include. the format of the standard has been re-written according to the relevant rules for standardization work.

1 Scope

This Standard specifies the vacuum oven method for determination of free water for the compound fertilizers.

This Standard is not applicable to the compound fertilizers generating non-moisture volatile substances during the drying process.

2 Normative References

The provisions in following documents become the provisions of this Standard through reference in this Standard. For dated references, the subsequent amendments (excluding corrigendum) or revisions do not apply to this Standard, however, parties who reach an agreement based on this Standard are encouraged to study if the latest versions of these documents are applicable. For undated references, the latest edition of the referenced document applies.

GB/T 8571 Preparation of Laboratory Samples for Compound Fertilizers

3 Apparatus

3.1 The common laboratory apparatus;

3.2 Thermostatic vacuum oven (vacuum oven). temperature can be controlled at 50°C±2°C; while the vacuum degree can be controlled at 6.4 x 10^4 Pa ~7.1 x 10^4 Pa;

4 Procedures

Do the parallel determination against two pieces of testing materials.

Prepare the laboratory sample as per the provisions of GB/T 8571.

5 Expression of Analytical Results