scope:

This European Standard specifies a method for determining the dissolved residual matter in liquefied petroleum gases (LPG), in the range of 40 mg/kg to 100 mg/kg. Higher concentrations can be determined by adjusting the sample size. The dissolved residue is the amount of organic compounds that are detectable by gas chromatography after evaporation of the sample at ambient temperature and then in an oven at 105 °C. This method is not suitable for detecting solid materials or for possibly high molecular weight polymers (> 1 000 g/mol). The advantages of this method are that a small quantity of LPG (50 g to 75 g) is required and the qualitative data available may indicate the origin of the residues (gas-oil, lubricants, plasticizers, etc.). This method has been developed as a potential replacement of the commonly used method described in EN ISO 13757, but is safer and more environmentally friendly. In addition, this new method is more accurate. The precision data of the method have been determined from 20 mg/kg to 100 mg/kg. For a higher content of residue, the precision has not been tested, but remains of lesser interest as typical specifications are in the range of 20 mg/kg to 100 mg/kg.