Test method of organic chemical products—
Part 2: Determination of dry residue after evaporation on a water bath for volatile organic liquids
Warning: Persons using this standard shall be familiar with normal laboratory practice. This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user to establish appropriate safety and health practices and to ensure compliance with any national regulatory conditions.
Attention is drawn to the potential hazards associated with the volatility, flammability, reactivity or toxicity of many of the products to which this test can be applied, and some solvents and chemical intermediates such as ethers and unsaturates may form peroxides in storage and the presence of peroxides can cause a strong explosion hazard. It is, therefore, essential that, for use of the method, careful consideration is given to the precautions necessary to eliminate the potential hazards.
Furthermore, all operations shall be carried out in a well-ventilated fume cupboard.
1 Scope
This part of GB/T 6324 specifies a general method for determination of dry residue, after evaporation on a water bath, of volatile organic liquids for industrial use.
This part is applicable to volatile organic liquids having residues after evaporation greater than or equal to 10 mg/kg [0.001% (m/m)]. If the residues after evaporation are less than 10 mg/kg [0.001% (m/m)], the sampling amount may be appropriately increased.
2 Normative references
The following documents contain provisions which, through reference in this text, constitute provisions of this part. For dated reference, subsequent amendments to (excluding any corrigendum), or revisions of, any of these publications do not apply. However, parties to agreements based on this part are encouraged to investigate the possibility of applying the latest editions of the standards indicated below. For any undated references, the latest edition of the document referred to applies.
GB/T 4472 General rule for determination of density and relative density for chemical products
3 Summary of method
Evaporation of a test portion on a water bath, and drying of the residue, if any, in an oven at (110±2)°C to constant mass.
4 Apparatus
4.1 Dish, of platinum, silica or borosilicate glass, of capacity about 150 ml.
4.2 Water bath, maintained at a temperature appropriate to the boiling point of the product under examination.
4.3 Oven: capable of being maintained at (110±2)°C.
5 Sampling
5.1 Procedures for sampling and sample preparation which are specific to a particular product being examined will be specified in the appropriate product standard.
5.2 Store the laboratory sample in a clean, dry, ground glass stoppered glass container of such capacity that it will be almost entirely filled by the sample. If it is necessary to seal the container, take care to avoid any risk of contamination of the sample.
6 Procedure
Introduce the dish into the oven at (110±2)°C for 2 h heating, allow it to cool in a desiccator to ambient temperature and weigh to the nearest 0.1 mg.
Foreword i
1 Scope
2 Normative references
3 Summary of method
4 Apparatus
5 Sampling
6 Procedure
7 Calculation of results
Annex A (Informative) Comparative list of references to the clauses/sub-clauses between this standard and ISO 759:1981
