Determination of octane numbers of gasoline compounds from their chemical structure by 13C NMR spectroscopy and neural networks

Abstract A new theoretical model has been developed which explains the association between the molecular structure and the knock resistance of individual gasoline compounds convincingly. The constitutions of more than 300 individual gasoline components were correlated with their knock rating (Blending Research Octane Number, BRON) simultaneously. 13C NMR spectra of all compounds were binned in 28 chemical shift regions of different size. The number of individual carbon signals of the nearly 2500 carbons was counted in each shift region and was combined with the information about the presence or absence of the structure groups Oxygen, Rings, Aromatics, aliphatic Chains and oLefins (ORACL). These numbers were used for the encoding of the chemical structure. The relations between the structure information and the knock ratings were determined using an artificial neural network. For a validation data set of 50 individual chemical compounds from various substance classes consisting only of C, H and O a good agreement was found with their experimentally determined BRON (R=0.933).

[1]  Brian E. Smith,et al.  Composition-property relations for jet and diesel fuels of variable boiling range , 1995 .

[2]  S. Beck,et al.  ELECTRODE EXTRAVAGANZA : PH ELECTRODES MEASURE UP TO THEIR POTENTIAL , 1998 .

[3]  Olav M. Kvalheim,et al.  Prediction of physical properties of hydrocarbon mixtures by partial-least-squares calibration of carbon-13 nuclear magnetic resonance data , 1989 .

[4]  R. Meusinger.  Gasoline analysis by 1H nuclear magnetic resonance spectroscopy , 1996 .

[5]  John M. Campbell,et al.  Detonation Characteristics of Some Aliphatic Olefin Hydrocarbons , 1931 .

[6]  Jean-Pascal Planche,et al.  Asphalt Study by Neuronal Networks. Correlation between Chemical and Rheological Properties , 1997 .

[7]  G. Edgar.  Measurement of Knock Characteristics of Gasoline in Terms of a Standard Fuel1 , 1927 .

[8]  José Manuel Andrade,et al.  Applicability of high-absorbance MIR spectroscopy in industrial quality control of reformed gasolines , 1999 .

[9]  Johann Gasteiger,et al.  Software Development in Chemistry, 4 , 1990 .

[10]  R. Meusinger.  Qualitative and quantitative determination of oxygenates in gasolines using 1H nuclear magnetic resonance spectroscopy , 1999 .

[11]  Brian E. Smith,et al.  1H and 13C n.m.r. spectroscopic methods for the analysis of fossil fuel materials: Some novel approaches☆ , 1982 .

[12]  Richard D. Gill,et al.  Octane number prediction based on gas chromatographic analysis with non-linear regression techniques , 1994 .

[13]  A. S. Sarpal,et al.  Estimation of Total Aromatics and Their Distribution as Mono and Global Di-Plus Aromatics in Diesel-Range Products by NMR Spectroscopy , 1998 .

[14]  R. Moros,et al.  Determination of quantitative structure–octane rating relationships of hydrocarbons by genetic algorithms , 1999 .

[15]  Alan Williams,et al.  The predictions of coal/char combustion rate using an artificial neural network approach , 1999 .

[16]  George M. Whitesides,et al.  FEED-FORWARD NEURAL NETWORKS IN CHEMISTRY : MATHEMATICAL SYSTEMS FOR CLASSIFICATION AND PATTERN RECOGNITION , 1993 .

[17]  PeterD. Wentzell.  Software development in chemistry : Software Development in Chemistry 4. Proceedings of the Workshop “Computers in Chemistry”, Hochfilzen/Tyrol, edited by J. Gasteiger, Springer-Verlag, 1990, DM 98.00, (viii + 419 pages), ISBN: 0-540-52173-9 , 1991 .

[18]  Ali Elkamel,et al.  MODELING THE HYDROCRACKING PROCESS USING ARTIFICIAL NEURAL NETWORKS , 1999 .

[19]  Lionello Pogliani,et al.  Molecular Modeling by Linear Combinations of Connectivity Indexes , 1995 .

[20]  Brian E. Smith,et al.  Determination of structural characteristics of saturates from diesel and kerosene fuels by carbon-13 nuclear magnetic resonance spectrometry , 1985 .

[21]  T. DeFries,et al.  Prediction of cetane number by group additivity and carbon-13 nuclear magnetic resonance , 1987 .

[22]  Brian E. Smith,et al.  Calculation of jet and diesel fuel properties using carbon-13 NMR spectroscopy , 1990 .

[23]  S.Win Lee,et al.  NMR method for determination of aromatics in middle distillate oils , 1999 .

[24]  K. Pihlaja,et al.  Carbon-13 NMR Chemical Shifts in Structural and Stereochemical Analysis , 1994 .

[25]  Lu Xu,et al.  A Newly Proposed Molecular Topological Index for the Discrimination of Cis/trans Isomers and for the Studies of QSAR/QSPR , 1992, Comput. Chem..