BS EN 12606-1-2000 pdf download.Methods of test for petroleum and its products — BS 2000-459.1: Bitumen and bituminous binders — Determination of the paraffin wax content —Part1: Method bydistillation (Identical with IP 459.1:2000).
8 Procedure
Melt each test portion in a porcelain crucible in accordance with EN 12594, pour 25 g ± 1 g into the distillation flask (6.3) and weight to the nearest 10 mg (mass m5).
Heat the distillation flask with a laboratory burner with a soft flame, approximately 150 mm high. (without flame cone) that has just ceased to be luminous in such a way that the first distillate drop falls down after 3 mm to 4 mm. Fit the sheet metal guard ring (see 6.4) loosely on the distillation flask to prevent possible burning of the cork stopper.
Ensure that the vapours produced dunng distillation are being condensed, by weighing, to the nearest 10 mg, the Erlenmeyer flask (6.7) into which the lower bent end of the outlet tube projects to its full length (see Figure 2), and immerse this as far as possible into a mixture of finely ground ice and water. The rate of distillation shall remain visible and capable of being checked.
Adjust the distillation rate so that 15 ± 5 drops fall from the end of the outlet tube into the distillation receiver every 10 S.
Continue heating, without adjustment of the laboratory burner flame, until the distillation rate slows and no drop falls from the outlet tube over a period of 10 s or after 14 mm from commencement of distillation.
Continue heating for a further minute with a completely non-luminous roaring flame until the flask glows red.
Complete the distillation in a maximum of 15 mm. Do not transfer the condensate left in the outlet tube after distillation to the distillation receiver.
Mix the distillate thoroughly by gently warming it whilst at the same time carefully swirling the receiver.
Cool in a desiccator to ambient temperature and weigh the distillate contained in the receiver to the nearest 10 mg (mass mD). Depending on the expected paraffin wax content, add 2 g to 4 g of the distillate into a test tube (6.5) and weigh to the nearest 5 mg (mass mE).
NOTE: If the paraffin wax content cannot be estimated in advance, an Initial mass of distillate of approximately 3 g is recommended
Dissolve the weighed mass of distillate in 25 ml ± 1 ml of ether (5.1) and add 25 ml ± 1 ml of ethanol (5.2).
Close the test tube with a stopper fitted with a sample thermometer (6.2.1) extending down into the liquid and place the test tube in a cooling bath. Cool the bath liquid by adding finely crushed solid carbon dioxide or with a cryostat (see note to 5.7). To ensure maintenance of the sample temperature of – 20 °C that will be required later, lower the bath temperature to -22 °C ± 1 °C.
Transfer 20 ml ± 1 ml of the washing liquid (5.9) into the test tube fitted with the wash bottle head and cool in the cooling bath (6.10) to -20 °C ± 0,5 °C, maintain this temperature until filtration is complete.
Place the round filter (6.18) in the funnel standing in the cooling bath and connect it to the filter flask placed below the cooling bath. Quickly transfer the slurry of crystals produced at
-20 °C ± 0,5 °C to the filter. Rinse the test tube with the cooled washing liquid. Re-adjust the temperature of the washing liquid to —20 °C ± 0,5 °C and use it again for rinsing the crystal slurry into the filter. Distribute the washing liquid as uniformly as possible between the three washing operations.
Support the filtration by a gentle vacuum process during which the pressure does not fall below 5 kPa. As soon as filtration is complete, lift off the round filter using pincers and place it in the funnel situated over the evaporating basin which has been weighed previously to the nearest 0,5 mg. Dissolve the crude paraffin wax residue by carefully spraying heated petroleum spirit over it. Dissolve in the same way any paraffin wax that may be adhering to the thermometer or to the test tube. Evaporate the mixed filtrates in the evaporating basin over the water bath. To prevent liquid creeping over the rim, carry out the evaporation in a weak air stream. Dry the residue for 15 mm ± 1 mm at 125 °C ± 5 °C in the oven and allow it to cool. When the previously purified paraffin waxes have cooled down but have not quite solidified, add approximately 15 ml of acetone.
Dissolve the paraffin waxes by gently heating and carefully swirling the evaporating basin. Make up any acetone lost by evaporation. Cool the acetone/paraffin wax solution in a water bath to 15,0 °C ± 0,5 °C and separate by filtering the paraffin waxes that crystallize out. Wash the evaporating basin, the thermometer and the filter several times with acetone brought to 15 °C ± 0,5 °C from a wash bottle ensuring that the total volume of washing liquid is 30 ml ± 1 ml.BS EN 12606-1-2000 pdf download.