The origin of light hydrocarbons in petroleum: Ring preference in the closure of carbocyclic rings

Other

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

Scientific paper

In a proposal for the generation of light hydrocarbons (LHs), n-alkane parents are catalytically transformed into daughter isoalkanes and cycloalkanes through the closure of three-, five-, and six-membered rings. Three reaction rate constants, k 3 : - isoalkanes; k 5 : cyclopentanes; k 6 : cyclohexanes, control this catalytic process, and thus the compositions of LHs. A catalyst that preferentially promotes ring-closure of a specific carbon number is said to express ring preference (RP) in that carbon number. For example, a catalyst that preferentially generates isoalkanes over cycloalkanes would be expressing three-ring preference (3RP), meaning that k 3 is greater than k 5 and k 6 in the catalytic process generating LHs. Oils show large compositional variations in LHs, with ratios of isoalkanes to cycloalkanes showing coefficients of variation on the order of 100%, reflecting large variations in RP. Genetically related oils (homologous oils), however, are either invariant in composition (invariant in RP) or they display systematic changes in RP. In a striking example of this latter case, RP progressively shifts to smaller rings, 6RP 5RP 3-RP, as parent concentrations increase. This paper addresses a curious paradox, apparently unique to the LHs: homologous oils, displaying a uniform overall geochemical composition (i.e., gravity, sulfur concentration, isotopic composition, biomarker composition, and so on), show remarkable changes in LH composition reflecting systematic changes in RP. These apparent contradictions, on the one hand a uniform overall composition reflecting a static system and on the other hand systematic changes in LH composition reflecting a dynamic system, are analyzed in the context of a steady-state catalytic hypothesis.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

The origin of light hydrocarbons in petroleum: Ring preference in the closure of carbocyclic rings does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with The origin of light hydrocarbons in petroleum: Ring preference in the closure of carbocyclic rings, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The origin of light hydrocarbons in petroleum: Ring preference in the closure of carbocyclic rings will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-869204

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.