Abstract
Two brown coal models were built to investigate the pyrolysis of coal using the ReaxFF molecular dynamics simulations. The Hatcher model and Morwell model were selected as representations of brown coal. For the purpose of studying the effect of heating rate on coal pyrolysis, ReaxFF-MD simulations were performed at temperatures from 300 to 2000 K with heating rate of 10, 100, and 1000 K/ps, respectively. Results showed that the pyrolysis reaction was enhanced under higher heating rate condition, and hydrogen, methyl, ethylene, acetylene, formaldehyde, and heavy compounds C14+ were the main products of coal pyrolysis. Plenty of radical fragments were also found in the pyrolysis process, and the pyrolysis reaction was promoted at high temperatures, which is consistent with the experimental results. The distributions of final products were greatly influenced by the initial structure of brown coal. The mass of aromatic nucleus mainly transformed into heavy char and tar (the C40+ compounds).
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References
Li CZ (2007) Some recent advances in the understanding of the pyrolysis and gasification behaviour of Victorian brown coal. Fuel 86:1664–1683
Li CZ, Sathe C, Kershaw JR, Pang Y (2000) Fates and roles of alkali and alkaline earth metals during the pyrolysis of a Victorian brown coal. Fuel 79:427–438
Quyn DM, Wu H, Hayashi JI, Li CZ (2004) Volatilisation and catalytic effects of alkali and alkaline earth metallic species during the pyrolysis and gasification of Victorian brown coal. Part IV. Catalytic effects of NaCl and ion-exchangeable Na in coal on char reactivity. Fuel 83:23–30
Solomon PR, Hamblen DG, Carangelo RM, Serio MA, Deshpande GV (1988) General model of coal devolatilization. Energy Fuels 2:405–422
Van Duin ACT, Dasgupta S, Lorant F, Goddard WA (2001) ReaxFF: a reactive force field for hydrocarbons. J Phys Chem A 105:9396–9409
Van Duin ACT, Damsté JSS (2003) Computational chemical investigation into isorenieratene cyclisation. Org Geochem 34:515–526
Alejandro S, Van Duin ACT, Debashis C, Siddharth D, Goddard WA (2003) Shock waves in high-energy materials: the initial chemical events in nitramine RDX. Phys Rev Lett 91:9105–9117
Kimberly C, Sam C, Van Duin ACT, Goddard WA, Kober EM (2005) Simulations on the thermal decomposition of a poly(dimethylsiloxane) polymer using the ReaxFF reactive force field. J Am Chem Soc 127:7192–7202
Kimberly C, Van Duin ACT, Goddard WA (2008) ReaxFF reactive force field for molecular dynamics simulations of hydrocarbon oxidation. J Phys Chem A 112:1040–1053
Chen N, Lusk MT, Van Duin ACT, Goddard WA III (2005) Mechanical properties of connected carbon nanorings via molecular dynamics simulation. Phys Rev B 72:085416
Van Duin ACT, Yehuda Z, Faina D, Ronnie K, Goddard WA (2005) Atomistic-scale simulations of the initial chemical events in the thermal initiation of triacetonetriperoxide. J Am Chem Soc 127:11053–11062
Sang Soo H, Van Duin ACT, Goddard WA, Hyuck Mo L (2005) Optimization and application of lithium parameters for the reactive force field, ReaxFF. J Phys Chem A 109:4575–4582
Buehler MJ, Van Duin ACT, Goddard WA (2006) Multiparadigm modeling of dynamical crack propagation in silicon using a reactive force field. Phys Rev Lett 96
Goddard W III, Merinov B, Van Duin ACT, Jacob T, Blanco M, Molinero V, Jang SS, Jang YH (2006) Multi-paradigm multi-scale simulations for fuel cell catalysts and membranes. Mole Simul 32:251–268(218)
Goddard WA III, Van Duin ACT, Chenoweth K, Cheng MJ, Pudar S, Oxgaard J, Merinov B, Yun HJ, Persson P (2006) Development of the ReaxFF reactive force field for mechanistic studies of catalytic selective oxidation processes on BiMoOx. Top Catal 38:93–103
Zhan JH, Wu R, Liu X, Gao S, Xu G (2014) Preliminary understanding of initial reaction process for subbituminous coal pyrolysis with molecular dynamics simulation. Fuel 134:283–292
Bhoi S, Banerjee T, Mohanty K (2014) Molecular dynamic simulation of spontaneous combustion and pyrolysis of brown coal using ReaxFF. Fuel 136:326–333
Salmon E III, Van Duin ACT, Lorant F, Marquaire P-M, Goddard WA III (2009) Thermal decomposition process in algaenan of Botryococcus braunii race L. Part 2: molecular dynamics simulations using the ReaxFF reactive force field. Org Geochem 40:416–427
Castro-Marcano F, Kamat AM, Russo MF, Van Duin ACT, Mathews JP (2012) Combustion of an illinois no. 6 coal char simulated using an atomistic char representation and the ReaxFF reactive force field. Combust Flame 159:1272–1285
Zhang J, Weng X, Han Y, Li W, Cheng J, Gan Z, Gu J (2013) The effect of supercritical water on coal pyrolysis and hydrogen production: a combined ReaxFF and DFT study. Fuel 108:682–690
Zheng M, Li X, Liu J, Li G (2013) Initial chemical reaction simulation of coal pyrolysis via ReaxFF molecular dynamics. Energy Fuels 27:2942–2951
Zheng M, Li X, Liu J, Wang Z, Gong X, Guo L, Song W (2014) Pyrolysis of liulin coal simulated by GPU-based ReaxFF MD with cheminformatics analysis. Energy Fuels 28:522–534
Chen B, Diao ZJ, Lu HY (2014) Using the ReaxFF reactive force field for molecular dynamics simulations of the spontaneous combustion of lignite with the Hatcher lignite model. Fuel 116:7–13
Lerch HE III, Verheyen TV, Hatcher PG, Bates AL (1989) Solid-state 13C nuclear magnetic resonance studies of coalified gymnosperm xylem tissue from Australian brown coals. Org Geochem 14:145–155
Hatcher PG (2002) Dipolar-dephasing 13C NMR studies of decomposed wood and coalified xylem tissue: evidence for chemical structural changes associated with defunctionalization of lignin structural units during coalification. Energy Fuels 2
Hatcher PG (1990) Chemical structural models for coalified wood (vitrinite) in low rank coal. Org Geochem 16:959–968
Salmon E, Behar F, Lorant F, Hatcher PG, Marquaire PM (2009) Early maturation processes in coal. Part 1: pyrolysis mass balance and structural evolution of coalified wood from the Morwell Brown Coal seam. Org Geochem 40:500–509
Salmon E, Behar F, Lorant F, Hatcher PG, Metzger P, Marquaire PM (2009) Thermal decomposition processes in algaenan of Botryococcus braunii race L. Part 1: experimental data and structural evolution. Org Geochem 40:400–415
Tersoff J (1988) New empirical approach for the structure and energy of covalent systems. Phys Rev B: Condens Matter 37:6991–7000
Berendsen HJC, Postma JPM, Gunsteren WFV, Dinola A, Haak JR (1984) Molecular dynamics with coupling to an external bath. J Chem Phys 81:3684–3690
Morishita T (2000) Fluctuation formulas in molecular-dynamics simulations with the weak coupling heat bath. J Chem Phys 113:2976–2982
Aktulga HM, Fogarty JC, Pandit SA, Grama AY (2012) Parallel reactive molecular dynamics: numerical methods and algorithmic techniques. Parallel Comput 38:245–259
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Financial support was sponsored by the Foundation of State Key Laboratory of Coal Combustion (FSKLCCB1507).
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Hong, Dk., Shu, Hk., Guo, X., Zheng, Cg. (2016). Molecular Dynamics Simulations Study of Brown Coal Pyrolysis Using ReaxFF Method. In: Yue, G., Li, S. (eds) Clean Coal Technology and Sustainable Development. ISCC 2015. Springer, Singapore. https://doi.org/10.1007/978-981-10-2023-0_8
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DOI: https://doi.org/10.1007/978-981-10-2023-0_8
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