A DFT study of the mechanism of H transfer during steam gasification

Zhao Deng; Liu Hui; Lu PengCheng; Yu HongYin; Qin Ming

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A DFT study of the mechanism of H transfer during steam gasification

机译：蒸汽气化过程中H转移机制的DFT研究

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The chemical reaction between a graphite model edge and H2O is crucial in steam gasification. This study used density functional theory (DFT) calculations to systematically evaluate the reaction path of steam gasification. The research results indicate that a graphite model edge without active cites is more suitable for use as an initial model for steam gasification. The aromaticity of the graphite model edge and the desorption of CO are linearly related. H atoms from H2O are transferred to the graphite model edge, destroying the aromaticity of the edge carbon structure and facilitating the subsequent desorption process, which may be the cause of the higher reactivity of steam compared to CO2 gasification. From a thermodynamic perspective, hydrogen transfer may be the rate-determining step of the overall reaction. The results of this paper can explain the kinetic differences in previous experiments that used water with varying isotopes of H (H2O vs D2O) and graphite in the gasification reaction (Yates and McKee, 1981; Mims and Pabst, 1987; Fletcher and Thomas, 2007). Our results provide new insights into the H transfer mechanism in steam gasification. (C) 2020 The Combustion Institute. Published by Elsevier Inc. All rights reserved.

机译：石墨模型边缘和H2O之间的化学反应在蒸汽气化中至关重要。本研究使用密度函数理论（DFT）计算来系统地评估蒸汽气化的反应路径。研究结果表明，没有活性CITES的石墨模型边缘更适合用作蒸汽气化的初始模型。石墨模型边缘的芳香性和CO的解吸是线性相关的。 H 2 O的H原子被转移到石墨模型边缘，破坏边缘碳结构的芳香性并促进随后的解吸过程，这可能是与CO 2气化相比蒸汽反应性更高的反应性的原因。从热力学的角度来看，氢转移可以是整体反应的速率确定步骤。本文的结果可以解释先前实验中的动力学差异，该实验中使用的水与气化反应中的H（H2O与D2O）和石墨中的不同同位素（Yates和McKee，1981; MIMS和Pabst，1987; Fletcher和Thomas，2007 ）。我们的结果为蒸汽气化中的H传输机制提供了新的见解。（c）2020燃烧研究所。由elsevier Inc.出版的所有权利保留。

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来源
《Combustion and Flame》 |2020年第9期|327-338|共12页
作者
Zhao Deng; Liu Hui; Lu PengCheng; Yu HongYin; Qin Ming;
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作者单位

Harbin Inst Technol Sch Energy Sci & Engn 92 West Da Zhi St Harbin 150001 Peoples R China;

Harbin Inst Technol Sch Energy Sci & Engn 92 West Da Zhi St Harbin 150001 Peoples R China;

Harbin Inst Technol Sch Energy Sci & Engn 92 West Da Zhi St Harbin 150001 Peoples R China;

Harbin Inst Technol Sch Energy Sci & Engn 92 West Da Zhi St Harbin 150001 Peoples R China;

Harbin Inst Technol Sch Energy Sci & Engn 92 West Da Zhi St Harbin 150001 Peoples R China;

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收录信息美国《科学引文索引》(SCI);美国《工程索引》(EI);美国《生物学医学文摘》(MEDLINE);
原文格式 PDF
正文语种 eng
中图分类
关键词
Density functional theory; Steam gasification; Hydrogen transfer; Aromaticity; Rate-determining step;

机译：密度函数理论;蒸汽气化;氢转移;芳香性;速率决定步骤;

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A DFT study of the mechanism of H transfer during steam gasification

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