Char structure evolution and behaviors of sodium species during catalytic gasification of sodium-rich direct coal liquefaction residue under CO<sub>2</sub> atmosphere

LI Pei; ZHU Chao-chao; HAN Lu; LI Xiao; FENG Xiao-bo; YAO Qin; YU Shi; MENG Xian-liang; WANG Peng; WEI Shuai

doi:10.1016/S1872-5813(22)60077-X

Volume 51 Issue 5

May 2023

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Article Navigation > Journal of Fuel Chemistry and Technology > 2023 > 51(5): 598-607

LI Pei, ZHU Chao-chao, HAN Lu, LI Xiao, FENG Xiao-bo, YAO Qin, YU Shi, MENG Xian-liang, WANG Peng, WEI Shuai. Char structure evolution and behaviors of sodium species during catalytic gasification of sodium-rich direct coal liquefaction residue under CO2 atmosphere[J]. Journal of Fuel Chemistry and Technology, 2023, 51(5): 598-607. doi: 10.1016/S1872-5813(22)60077-X

Citation:

LI Pei, ZHU Chao-chao, HAN Lu, LI Xiao, FENG Xiao-bo, YAO Qin, YU Shi, MENG Xian-liang, WANG Peng, WEI Shuai. Char structure evolution and behaviors of sodium species during catalytic gasification of sodium-rich direct coal liquefaction residue under CO₂ atmosphere[J]. Journal of Fuel Chemistry and Technology, 2023, 51(5): 598-607. doi: 10.1016/S1872-5813(22)60077-X

Citation:

LI Pei, ZHU Chao-chao, HAN Lu, LI Xiao, FENG Xiao-bo, YAO Qin, YU Shi, MENG Xian-liang, WANG Peng, WEI Shuai. Char structure evolution and behaviors of sodium species during catalytic gasification of sodium-rich direct coal liquefaction residue under CO₂ atmosphere[J]. Journal of Fuel Chemistry and Technology, 2023, 51(5): 598-607. doi: 10.1016/S1872-5813(22)60077-X

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Char structure evolution and behaviors of sodium species during catalytic gasification of sodium-rich direct coal liquefaction residue under CO₂ atmosphere

doi: 10.1016/S1872-5813(22)60077-X

LI Pei^1
,,
ZHU Chao-chao^1
,,
HAN Lu^1
,,
LI Xiao^{1
,
,},
FENG Xiao-bo^1
,,
YAO Qin^1
,,
YU Shi^1
,,
MENG Xian-liang^1
,,
WANG Peng^2
,,
WEI Shuai^2
,

1.
Key Laboratory of Coal Processing and Efficient Utilization, Ministry of Education, China University of Mining and Technology, Xuzhou 221116, China
2.
School of Materials and Chemical Engineering, Xuzhou University of Technology, Xuzhou 221018, China

Funds: The project was supported by National Key Research and Development Program of China (2022YFC2905900), Xuzhou Science and Technology Plan Project (KC20190), the National Natural Science Foundation of China (21903087, 22201243), and Experimental technology research and development project of China University of Mining and Technology (S2021Y006)

More Information

Corresponding author: E-mail: lixiao@cumt.edu.cn
Received Date: 2022-09-29
Accepted Date: 2022-10-25
Rev Recd Date: 2022-10-25

Available Online: 2022-12-26

Publish Date: 2023-05-15

Abstract

Abstract

In this work, to better understand catalytic gasification process of direct coal liquefaction residue rich in sodium species, char structure evolution and behaviors of sodium species during gasification under CO₂ atmosphere were investigated in detail by N₂ adsorption and desorption, FT-IR, XRD, SEM, and Raman analyses. The results show that sodium species developed pore structure of direct coal liquefaction residue during gasification, especially expanded mesoporous structures which increased from 0.05 to 0.16 cm³/g at maximum. With the increase of gasification time, different crystalline compounds were formed in chars. Most of the mineral matters identified by XRD were calcium-containing ones, whereas no obvious sodium-containing crystalline compounds were found. This was because that most of sodium species volatilized at high temperature and the crystalline forms of sodium-containing compounds had defects. Compared with sodium species, calcium species were more prone to react with aluminosilicates, which happened to make sodium species remain active during gasification process. The ratio of (G_R + V_L + V_R)/D rose initially and then decreased, which could be explained as the dissociation of the large aromatic and the rearrangement of small aromatic rings into large aromatic structures. Moreover, release ratio of sodium species was closely related with gasification time and 49.8% of them released in the initial stage of gasification process (within 15 min). Compared with that of direct coal liquefaction residue reloaded with water-soluble sodium species, the release ratio of sodium species in the original direct coal liquefaction residue was on a lower level (85.2% versus 89.7%).
- char structure,
- sodium species,
- calcium species,
- catalytic gasification,
- direct coal liquefaction residue

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References(28)

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