The present application provides a method and system for the characterization of properties of liquids, particularly petroleum and petroleum liquids. The method and system can be used to take measurements of the liquid directly in a storage container, without exposing the contents of the container to the external environment.

The present application provides a method and system for the characterization of properties of liquids, particularly petroleum and petroleum liquids. The method and system can be used to take measurements of the liquid directly in a storage container, without exposing the contents of the container to the external environment.

The present application provides a method and system for the characterization of properties of liquids, particularly petroleum and petroleum liquids. The method and system can be used to take measurements of the liquid directly in a storage container, without exposing the contents of the container to the external environment.

The present application provides a method and system for the characterization of properties of liquids, particularly petroleum and petroleum liquids. The method and system can be used to take measurements of the liquid directly in a storage container, without exposing the contents of the container to the external environment.

A method and apparatus for calculating the derived cetane number of a liquid hydrocarbon sample is disclosed. The method comprises combusting (19) the sample in a constant volume combustion chamber (45). The method comprises obtaining (23) a pressure versus time combustion profile (69) of the sample wherein the profile comprises a first region (81) and a second region (83), the first region (81) including the start of combustion, and the second region (83) relating to a later time than the first region. The method comprises selecting a single data point from the second region (83) of the combustion profile (69), said data point representing a combustion delay (CD) of the combustion profile; and calculating a derived cetane number for the sample using the time value associated with said single data point.

A method and apparatus for calculating the derived cetane number of a liquid hydrocarbon sample is disclosed. The method comprises combusting (19) the sample in a constant volume combustion chamber (45). The method comprises obtaining (23) a pressure versus time combustion profile (69) of the sample wherein the profile comprises a first region (81) and a second region (83), the first region (81) including the start of combustion, and the second region (83) relating to a later time than the first region. The method comprises selecting a single data point from the second region (83) of the combustion profile (69), said data point representing a combustion delay (CD) of the combustion profile; and calculating a derived cetane number for the sample using the time value associated with said single data point.

A method and apparatus for calculating the derived cetane number of a liquid hydrocarbon sample is disclosed. The method comprises combusting (19) the sample in a constant volume combustion chamber (45). The method comprises obtaining (23) a pressure versus time combustion profile (69) of the sample wherein the profile comprises a first region (81) and a second region (83), the first region (81) including the start of combustion, and the second region (83) relating to a later time than the first region. The method comprises selecting a single data point from the second region (83) of the combustion profile (69), said data point representing a combustion delay (CD) of the combustion profile; and calculating a derived cetane number for the sample using the time value associated with said single data point.

A method and apparatus for calculating the derived cetane number of a liquid hydrocarbon sample is disclosed. The method comprises combusting (19) the sample in a constant volume combustion chamber (45). The method comprises obtaining (23) a pressure versus time combustion profile (69) of the sample wherein the profile comprises a first region (81) and a second region (83), the first region (81) including the start of combustion, and the second region (83) relating to a later time than the first region. The method comprises selecting a single data point from the second region (83) of the combustion profile (69), said data point representing a combustion delay (CD) of the combustion profile; and calculating a derived cetane number for the sample using the time value associated with said single data point.

Methods of extracting 1-4 cycle heterocyclic compounds and 2-5 cycle polynuclear aromatic hydrocarbons from a hydrocarbon feedstock are described. The methods include providing a hydrocarbon feedstock containing crude oil fractions, and determining an A/R ratio and an asphaltene concentration of the hydrocarbon feedstock. Based upon the A/R ratio and the asphaltene concentration, the treatable hydrocarbon feedstock undergoes one or more of cracking and fractionating. Subsequently, at least one targeted portion of the heterocyclic compounds is extracted from the fractionated stream with an aqueous solvent. A stream containing the 2-5 cycle polynuclear aromatic hydrocarbons is transferred to an extractor and the 2-5 cycle polynuclear aromatic hydrocarbons are extracted with a solvent system comprising an aprotic solvent.

Methods of extracting 1-4 cycle heterocyclic compounds and 2-5 cycle polynuclear aromatic hydrocarbons from a hydrocarbon feedstock are described. The methods include providing a hydrocarbon feedstock containing crude oil fractions, and determining an A/R ratio and an asphaltene concentration of the hydrocarbon feedstock. Based upon the A/R ratio and the asphaltene concentration, the treatable hydrocarbon feedstock undergoes one or more of cracking and fractionating. Subsequently, at least one targeted portion of the heterocyclic compounds is extracted from the fractionated stream with an aqueous solvent. A stream containing the 2-5 cycle polynuclear aromatic hydrocarbons is transferred to an extractor and the 2-5 cycle polynuclear aromatic hydrocarbons are extracted with a solvent system comprising an aprotic solvent.