Quality of Distillates from Repeated Recycle of Residue

The yields of gas, liquid, and coke from the coking of Athabasca vacuum residue were determined as a function of conversion of the residue. High conversion was achieved by subjecting the unconverted residue to repeated coking steps. The cumulative yield of liquid increased by 12% from stage 1 of coking, where 80% residue conversion was obtained, to stage 3 where over 97% cumulative residue conversion was obtained. The quality of the distillates obtained at each stage deteriorated based on the concentrations of nitrogen and polyaromatic hydrocarbons. Although coking reactions resulted in a significant decrease in the number of paraffinic chains, the average chain length remained constant. A mass balance showed that the aromatic carbon increased in the first coking step, then remained constant.

[1]  Narrow-cut characterization reveals resid process chemistry , 2001 .

[2]  L. Kotlyar,et al.  Effect of Thermal and Hydro-Catalytic Treatment on the Molecular Chemistry of Narrow Fractions of Athabasca Bitumen Pitch , 2001 .

[3]  S. Jain,et al.  Hydrocarbon characterization of hydrocracked base stocks by one- and two-dimensional n.m.r. spectroscopy , 1996 .

[4]  I. Wiehe,et al.  The Pendant-Core Building Block Model of Petroleum Residua , 1994 .

[5]  E. C. Sanford.  Molecular approach to understanding residuum conversion , 1994 .

[6]  Kenneth E. Peters,et al.  Effects of refinery processes on biological markers , 1992 .

[7]  R. Greinke.  Chemical bond formed in thermally polymerized petroleum pitch , 1992 .

[8]  R. Reynolds,et al.  Anomalous side-chain cleavage in alkylaromatic thermolysis , 1991 .

[9]  P. Savage,et al.  Reactions of polycyclic alkylaromatics: Structure and reactivity , 1991 .

[10]  D. Trimm,et al.  Coke formation on catalysts during the hydroprocessing of heavy oils , 1991 .

[11]  J. Ripmeester,et al.  Structural analysis of Athabasca maltenes fractions using distortionless enhancement by polarization transfer (DEPT) related 13C n.m.r. sequences , 1991 .

[12]  Richard F. Sullivan,et al.  Molecular transformations in hydrotreating and hydrocracking , 1989 .

[13]  M. Gray,et al.  13C-NMR OF SOLID ORGANIC DEPOSITS ON SPENT HYDROPROCESSING CATALYSTS , 1989 .

[14]  D. Grant,et al.  Carbon-13 solid-state NMR of Argonne-premium coals , 1989 .

[15]  M. Gray,et al.  Structural analysis of extracts from spent hydroprocessing catalysts , 1988 .

[16]  E. C. Sanford,et al.  Structural group analysis of residues from Athabasca bitumen , 1988 .

[17]  D. Netzel.  Quantitation of carbon types using DEPT/QUAT NMR pulse sequences: application to fossil-fuel-derived oils , 1987 .

[18]  P. Savage,et al.  Asphaltene reaction pathways. 2. Pyrolysis of n-pentadecylbenzene , 1987 .

[19]  Michael G. Thomas,et al.  Catalyst deactivation in heavy petroleum and synthetic crude processing: a review , 1985 .

[20]  K. Bartle,et al.  Definition of fossil fuel-derived asphaltenes in terms of average structural properties , 1984 .

[21]  Toshimitsu Suzuki,et al.  Chemical structure of tar-sand bitumens by 13C and 1H n.m.r. spectroscopic methods , 1982 .

[22]  E. Furimsky.  Characterization of deposits formed on catalyst surfaces during hydrotreatment of coal-derived liquids , 1982 .

[23]  F. D. Guffey,et al.  1H- and 13C-n.m.r. studies on naphtha and light distillate saturate hydrocarbon fractions obtained from in-situ shale oil , 1981 .

[24]  W. R. Ladner,et al.  Survey of carbon-13 chemical shifts in aromatic hydrocarbons and its application to coal-derived materials , 1979 .

[25]  P. Fu,et al.  Dehydrogenation of polycyclic hydroaromatic compounds , 1978 .

[26]  E. Furimsky.  Chemical Origin of Coke Deposited on Catalyst Surface , 1977 .

[27]  C. Wilke,et al.  Correlation of diffusion coefficients in dilute solutions , 1955 .