Method and equipment for the simulated distillation by means of gas chromatography with non vaporizing direct injection

Claim 1

A method of the simulated distillation of petroleum products utilizing apparatus adapted for chromatographic analysis including a capillary column wherein said capillary column has an inner diameter ranging between 0.2 and 0.6 mm and a length between 1 and 10 m, said capillary column having therein a thin film stationary phase less than or equal to 0.2 μm, said capillary column having a first end and a second end and having associated with said first end of said capillary column a direct nonvaporizing cold on-column injector and an oven in which said capillary column is housed, said oven being programmable to reach temperatures over 400° C. at a speed equal to at least 5° C. per minute and wherein said apparatus has a flame ionization detector connected to said second end of said column, said method comprising the steps of: (a) injecting into said column utilizing said direct cold on-column injector an appropriately diluted sample of a sample petroleum product; (b) performing a gas chromatographic analysis on said sample petroleum product using said apparatus at a preprogrammed temperature having a temperature end point greater than 400° C.; (c) converting said time axis of said chromatogram obtained from said gas chromatographic analysis of said sample petroleum product into a boiling point axis by using a standard calibration mixture which generates a standard curve; and (d) integrating in slices the surface between the sample elution curve and the chromatogram base line to obtain a simulated distillation boiling point distribution curve.

Claim 2

A method of the simulated distillation of petroleum products utilizing apparatus adapted for chromatographic analysis including a capillary column wherein said capillary column has an inner diameter ranging between 0.2 and 0.6 mm and a length between 1 and 10 m, said capillary column having therein a thin film stationary phase less than or equal to 0.2 μm, said capillary column having a first end and a second end and having associated with said first end of said capillary column a direct nonvaporizing cold on-column injector and an oven in which said capillary column is housed, said oven being programmable to reach temperatures over 400° C. at a speed equal to at least 5° C. per minute and wherein said apparatus has a flame ionization detector connected to said second end of said column, said method comprising the steps of: (a) injecting into said column utilizing said direct cold on-column injector an appropriately diluted sample of a sample petroleum product; (b) performing a gas chromatographic analysis on said sample petroleum product using said apparatus at a preprogrammed temperature having a temperature end point greater than 400° C.; (c) converting said time axis of said chromatogram obtained from said gas chromatographic analysis of said sample petroleum product into a boiling point axis by using a standard calibration mixture which generates a standard curve; and (d) integrating in slices the surface between the sample elution curve and the chromatogram base line to obtain a simulated distillation boiling point distribution curve.