ISO 3924-2010 pdf free download

ISO 3924-2010 pdf free download.Petroleum products — Determination of boiling range distribution — Gas chromatography method
Produits petroliers — Determination de Ia repartition dans I’intervalle de distillation — Méthode par chromatographie en phase gazeuse.
9.1.2 After the chromatographic conditions have been set to meet performance requirements, programme the column temperature upward to the maximum temperature being used and hold at that temperature for the selected time. Following the analysis sequence protocol, cool the column to the initial starting temperature.
9.1.3 During the cool-down and equilibration time, prepare the integrator/computer system for data acquisition. If a retention-time or detector-response calibration is being performed, use the peak detection mode. For samples and baseline-compensation determinations, use the area-slice mode of integration. The recommended slice rate for this method is 1 Hz (one slice per second).
9.1.4 At the exact time set by the schedule, inject either the calibration mixture or sample into the chromatograph; or make no injection (baseline blank). At the time of injection, start the chromatograph time cycle and the integrator/computer data acquisition. Follow this analysis sequence protocol for all subsequent analysis, blanks and calibrations.
9.2 Baseline compensation analysis
A baseline compensation analysis, or baseline blank, shall be performed at least once each day that the test is run, using the same technique for a sample analysis except that no injection is made.
NOTE 1 The blank analysis is necessary due to the normal occurrence of chromatograptiec baseline rise near the maximum column temperature. Factors that influence baseline stability are column bleed, septum bleed, detector temperature control, constancy of carrier and detector gas flows, leaks, instrument drift, etc.
Subtract the blank analysis from the sample analysis to remove any non-sample slice area from the chromatographic data.
NOTE 2 The blank analysis is typically performed prior to sample analysis, but can be useful if determined between samples or at the end of a sample sequence to provide additional data regarding instrument operation or residual sample carry-over from previous sample analysis.
Carry out periodic baseline blank analysis in accordance with the analysis sequence protocol to give an indication of baseline stability.
9.3 Retention time versus boiling point calibration
9.3.1 A retention-time versus boiling-point calibration shall be performed at least once each day that the test is run. Inject an appropriate aliquot (0.2 p1 to 2,0 p1) of the calibration mixture into the chromatograph following the analysis sequence protocol.
9.3.2 Prepare a calibration table based on the results of the analysis of the calibration mixture by recording the retention time and the normal bolling point temperature for each component In the mixture. Boiling point temperatures of alkanes are listed in Table 1.ISO 3924-2010 pdf free download.