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Title: Composition of heavy petroleums. 2. Molecular characterization

Journal Article · · Energy Fuel; (United States)
DOI:https://doi.org/10.1021/ef00011a001· OSTI ID:6020610

The objective of this paper is to illustrate the variation of the chemical composition of heavy petroleums as a function of atmospheric equivalent boiling point (AEBP) up to approximately 1400/degrees/F and further as a function of solubility down to the bottom of the barrel. The first paper in this series described the variation of heteroatom (S, N, O, V, Ni, Fe) concentrations, hydrogen deficiency (H/C atomic ratio), and molecular weight distribution. This paper describes the variation of the chemical composition of heavy petroleums on the molecular level. Two molecular characterization approaches are discussed. The first approach utilizes average molecular parameters. The data illustrate the changes in relative concentrations of the molecular building blocks with increasing AEBP and decreasing solubility of heavy crude components. The second approach involves the extensive us of high-performance liquid chromatography (HPLC) to separate compound-class fractions for further molecular characterization. The results are expressed in terms of the homologous series of compounds and their carbon number distributions by using field-ionization mass spectrometry (FIMS). The results help unravel the immense complexity of heavy petroleums. Data show the great diversity of molecular types, involving numerous homologous series of compounds, each series having a very wide carbon number distribution extending to over C/sub 100/ and very low relative concentrations of individual carbon number homologues (from a few tenths of 1 wt% to less than 1 ppm by weight).

Research Organization:
Chevron Research Company, Richmond, CA (USA)
OSTI ID:
6020610
Journal Information:
Energy Fuel; (United States), Vol. 2:5
Country of Publication:
United States
Language:
English