71.080.10 - Aliphatic hydrocarbons

Describes the procedure and the precautions to be taken in drawing representative samples of the substances for the purpose of their analyses. It also sets out, in Annex A, a diagrammatic representation of a system for the disposal of the portion of the sample not used in the analysis, and, in Annex B, the sequence of operations for filling a sample cylinder.

Describes the procedure and the precautions to be taken in drawing representative samples of ethylene in the liquid phase stored at -100 °C and in the gaseous phase, for the purpose of their analysis excluding the determination of water content, other polar components and hydrocarbons heavier than C5. In an annex a diagrammatic representation is given of a system for the removal of the portion of the sample not used in the analysis.

The method comprises the passage of a gaseous test portion through water to absorb acetone, acetonitrile, propan-2-ol and methanol, and subsequent gas chromatographic analysis of the aqueous solution, using a flame ionization detector, and comparison of the peaks obtained with those derived from an external standard. The method is applicable to products having acetone, propan-2-ol and methanol concentrations greater than 1 mg/kg, and acetonitrile concentrations greater than 10 mg/kg.