Reducing the Carbon Footprint of Transportation Fuels through Computational Modelling

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Tyrone Johnston
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1 Reducing the Carbon Footprint of Transportation Fuels through Computational Modelling

2 Computational Modelling Group Founded in 1999 Head Prof. Currently 20 members (PhDs, PDRAs) Theme: Modelling across the length scales

3 Computational Modelling Group Emphasis: Combustion Particulate processes (nanoparticles, soot) Emissions from Internal Combustion Engines Methods: Quantum chemistry Population balance modelling Computational Fluid Dynamics Process optimisation

4 Computational Modelling Group Emissions from internal combustion engines: Stochastic Reactor Model CO, uhc, NOx, etc. through detailed chemical kinetics Soot through detailed population balance models

5 Computational Modelling Group Process Informatics: Effective use of cost-intensive experimental data through data standardisation Robust model development through systematic optimisation, accounting for uncertainties Design of experiments

6 Reducing CO 2

7 Typical Oil Refinery Physical Separation Chemical Processing Gasoline Blending

8 Blending to Specifications Table of key specifications for commercial gasoline, as set out by EN-228 Chemical Physical

9 Overview Optimisation Programme Use cost to indicate carbon intensity of fuel Octane number important parameter. Octane Tests Knowledge of Blending Pots Chemical Kinetic Fuel Model

10 Choice of Chemical Surrogates GASOLINE PARAFFINS C4-C7 range NAPHTHENES C6 C7 range OLEFINS C5 C7 range AROMATICS C6 C8 range OXYGENATES Ethanol or MTBE ANTI-KNOCK BLENDING POTS ETBE C3 Alkylate C4 Alkylate Cat Cracked Light Naphtha Cat Cracked Heavy Naphtha Isomerate Reformate SURROGATE SPECIES Ethanol N-heptane Iso-octane N-butane Toluene Methyl-cyclohexane Di-isobutylene

11 Overview Optimisation Programme Use cost to indicate carbon intensity of fuel Octane number important parameter. Octane Tests Knowledge of Blending Pots Chemical Kinetic Fuel Model

Chemical Kinetic Fuel Model (k = A T**b exp(-e/rt)) 24. H2O2+H=HO2+H2 1.98E+06 2.0 2435.0 REACTIONS CONSIDERED A b E 25. H2O2+H=OH+H2O 3.07E+13 0.0 4217.0 26. H2O2+O=OH+HO2 9.55E+06 2.0 3970.0 1.

0 Low pressure limit: 0.11400E+37-0.52460E+01 0.17050E+04 4. H+O2(+M)=HO2(+M) 4.52E+13 0.0 0.0 CO Enhanced by 2.000E+00 iso-octane, Low pressure limit: 0.10500E+20 n-heptane, -0.12570E+01 0.

12 Chemical Kinetic Fuel Model (k = A T**b exp(-e/rt)) 24. H2O2+H=HO2+H2 1.98E REACTIONS CONSIDERED A b E 25. H2O2+H=OH+H2O 3.07E H2O2+O=OH+HO2 9.55E OH+H2=H+H2O 2.14E H2O2+OH=H2O+HO2 2.40E Reduced 2. O+OH=O2+H mechanism 2.02E for 28. CH3+CH3(+M)=C2H6(+M) 9.22E O+H2=OH+H 5.06E Low pressure limit: E E E H+O2(+M)=HO2(+M) 4.52E CO Enhanced by 2.000E+00 iso-octane, Low pressure limit: E+20 n-heptane, E E+00 TROE centering: E E E E+16 CH4 Enhanced by 1.000E CH3+H(+M)=CH4(+M) 2.14E H+O2(+N2)=HO2(+N2) 4.52E Low pressure limit: E E E+04 toluene Low pressure limit: E+18 and E+01 ethanol E+00 CO Enhanced by 2.000E H+O2(+H2)=HO2(+H2) 4.52E TROE centering: E E E E+02 Low pressure limit: E E E CH4+H=CH3+H2 2.20E chosen H+O2(+H2O)=HO2(+H2O) as base 4.52E CH4+OH=CH3+H2O 4.19E Low pressure limit: E E E CH4+O=CH3+OH 6.92E OH+HO2=H2O+O2 2.13E CH4+HO2=CH3+H2O2 1.12E mechanism. Declared duplicate reaction CH3+HO2=CH3O+OH 7.00E OH+HO2=H2O+O2 9.10E CH3+HO2=CH4+O2 3.00E Declared duplicate reaction CH3+O=CH2O+H 8.00E H+HO2=OH+OH 1.50E CH3+O2=CH3O+O 1.45E Di-isobutylene, 11. H+HO2=H2+O2 6.63E CH3+O2=CH2O+OH 2.51E H+HO2=O+H2O 3.01E CH3O+H=CH3+OH 1.00E O+HO2=O2+OH 3.25E CH2OH+H=CH3+OH 1.00E methylcyclohexane OH+OH=O+H2O 3.57E and CH3+OH=CH2(S)+H2O 2.00E H+H+M=H2+M 1.00E CH3+OH=HCOH+H2 1.00E H2 Enhanced by 0.000E CH3+OH=CH2+H2O 3.00E butane H+H+H2=H2+H2 added. 9.20E CH3+H=CH2+H2 9.00E H+H+H2O=H2+H2O 6.00E CH3+M=CH+H2+M 6.90E H+OH+M=H2O+M 2.21E CH3+M=CH2+H+M 1.90E H2O Enhanced by 6.400E CH3+OH(+M)=CH3OH(+M) 8.70E H+O+M=OH+M 4.71E Low pressure limit: E E E+03 H2O Enhanced by 6.400E+00 CO Enhanced by 2.000E Resulting O+O+M=O2+M model 1.89E+13 contains TROE chemical centering: E-01 species E E+04 and E HO2+HO2=H2O2+O2 4.20E CH3OH(+M)=CH2(S)+H2O(+M) 2.84E Declared duplicate reaction... Low pressure limit: E E E chemical HO2+HO2=H2O2+O2 reactions. 1.30E CO Enhanced by 2.000E OH+OH(+M)=H2O2(+M) 1.24E TROE centering: E E E E+04 Low pressure limit: E E E CH3OH(+M)=HCOH+H2(+M) 4.20E TROE centering: E E E E+16 Low pressure limit: E E E+05 CO Enhanced by 2.000E+00 TROE centering: E E E E+04

13 Mechanism Reduction Removal of species and reactions Toluene Flux: Full Mechanism Toluene Flux: Skeletal Mechanism

14 Fuel Model Optimisation

15 Overview Optimisation Programme Use cost to indicate carbon intensity of fuel Octane number important parameter. Octane Tests Knowledge of Blending Pots Chemical Kinetic Fuel Model

16 Modelling Octane Number Industrially, octane number determined using engine test. Model used to predict octane number from fuel composition. Engine test required to predict octane number accurately.

17 Further Work Optimisation Programme Use cost to indicate carbon intensity of fuel Octane number important parameter. Octane Tests Knowledge of Blending Pots Chemical Kinetic Fuel Model

18 The End Thank you

Toward a multilevel QM/MM methodology for performing molecular dynamic simulations of complex reactive processes

Toward a multilevel QM/MM methodology for performing molecular dynamic simulations of complex reactive processes Michael R. Salazar Department of Chemistry Union University, Jackson, TN 38305 msalazar@uu.edu