烟煤热解过程分子官能团的演化特征及动力学模型

杨琦玲; 王儒威

doi:10.13205/j.hjgc.202307019

烟煤热解过程分子官能团的演化特征及动力学模型

doi: 10.13205/j.hjgc.202307019

杨琦玲¹,
王儒威^1,2, ,

1. 暨南大学环境学院, 广州 511443;
2. 广东工业大学环境健康与污染控制研究院环境科学与工程学院粤港澳污染物暴露与健康联合实验室, 广州 510006

基金项目:

国家自然科学基金项目（41773099）

详细信息

作者简介:
杨琦玲(1996-),女,硕士,主要研究方向为燃煤环境化学过程。895294222@qq.com

通讯作者:
王儒威(1985-),男,副教授,主要研究方向为环境有机地球化学。wangruwei@jnu.edu.cn

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出版历程
- 收稿日期: 2022-09-24

EVOLUTION CHARACTERISTIC AND KINETIC MODEL FOR FUNCTIONAL GROUPS IN BITUMINOUS COAL DURING PYROLYSIS

YANG Qiling¹,
WANG Ruwei^{1,2
, ,}

1. School of Environment, Jinan University, Guangzhou 511443, China;
2. Guangdong-Hongkong-Macao Joint Laboratory for Contaminants Exposure and Health, School of Environmental Science and Engineering, Institute of Environmental Health and Pollution Control, Guangdong University of Technology, Guangzhou 510006, China

摘要

摘要: 煤热解机理研究对提高煤炭利用效率和减轻生态环境影响具有重要意义。利用傅里叶红外光谱（FTIR）和气相色谱-质谱分析探究煤分子结构官能团和多环芳烃（PAHs）在煤热解过程中的演化特征及热解动力学行为。结果表明：当温度<300℃时，芳香族和脂肪族官能团减少主要缘于煤结构空隙小分子基团的挥发，含氧官能团减少主要因为在该热演化过程中自缔合羟基氢键受热断裂；当温度在300~600℃区间，C—O和脂肪族分别在300，400℃时受热分解，导致芳香族、脂肪族和含氧官能团总量迅速减少。各官能团在高温阶段的活化能均高于低温阶段，·OH和C—O在整个热解阶段的动力学模型均符合二级反应模式，脂肪族官能团在25~400，400~600℃区间分别符合两相界面模型和二级反应模式，C=O在25~300，300~600℃区间分别符合三级扩散和二级反应模式。
- 烟煤热解 /
- 官能团 /
- 演化特征 /
- 动力学模型
Abstract: Understanding the mechanism of coal pyrolysis is of great significance to improving coal utilization efficiency and mitigating environmental impact. Fourier transform infrared spectroscopy (FTIR) and gas chromatogram-mass spectrum analyses were used to investigate changes in molecular functional groups and polycyclic aromatic hydrocarbons (PAHs) during pyrolysis of bituminous coal, and then kinetic models were constructed. Results showed that:the relative abundances of aromatic, aliphatic, and heteroatom functional groups decreased as pyrolysis temperature increased. When the temperature was lower than 300℃, the reduction of aromatic and aliphatic functional groups was mainly due to the volatilization of the small molecular groups, while the reduction of oxygen-containing functional groups was due to thermal breakage of self-associating hydroxyl hydrogen bonds; when the temperature was 300~600℃, the functional groups of C-O and aliphatics were decomposed at 300℃ and 400℃, leading to rapid decreases in relative abundances of aromatic, aliphatic and oxygen-containing functional groups. The activation energy of each functional group at high temperature stage was higher than that at low temperature stage. The kinetic models of ·OH and C-O in the whole pyrolysis process followed the second-order reaction mode. Changes in the aliphatic functional groups conformed to the two-phase interface model at 25 to 400℃, and conformed to the second-order reaction model at 400 to 600℃. C=O conformed to the three-way transport mode and the second-order reaction model at 25 to 300℃ and 300 to 600℃, respectively.
- pyrolysis of bituminous coal /
- functional groups /
- evolution characteristic /
- kinetic model

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