文献类型：期刊文献

英文题名：Volatile potassium transfer behavior in carbon matrix and its effect on char gasification

作者：Wang, Xingjun[1];Chen, Qian[1];Wei, Bing[1];Yu, Guangsuo[1];Li, Hongxia[2];Chen, Xueli[1];Liu, Haifeng[1];Wang, Fuchen[1]

机构：[1]East China Univ Sci & Technol, Inst Clean Coal Technol, Shanghai Engn Res Ctr Coal Gasificat, POB 272, Shanghai 200237, Peoples R China;[2]Sinosteel Luoyang Inst Refractories Res Co Ltd, State Key Lab Adv Refractories, Luoyang 471039, Henan, Peoples R China

年份：2023

卷号：333

外文期刊名：FUEL

收录：;EI(收录号：20224313004387);WOS:【SCI-EXPANDED(收录号:WOS:000878641900002)】；

基金：Funding information This work is jointly supported by the National Natural Science Foundation of China (U21A2059) . The experiment was assisted by Analytical and Testing Center in East China University of Science and Technology.

语种：英文

外文关键词：In -situ HTSM; Volatile potassium; Migration distance; Catalytic char gasification

摘要：Coal catalytic gasification is one of the effective ways to produce natural gas from coal. However, high cost and low recovery efficiency of catalyst increase the cost of catalytic gasification, which has become a restrictive factor for large-scale promotion of coal catalytic gasification. Therefore, the study on the migration behavior of potassium-based catalysts in the gasification process is of great significance for catalysts recovery. To understand the volatilization behavior between potassium and carbon matrix, the experiments were carried out in high temperature stage microscope (HTSM) and fixed-bed reactor. The migration of volatile potassium between particles was analyzed by SEM-EDS, while the chemical fraction of potassium species was determined by AAS, and the surface elements of the samples was investigated by XPS. The results showed that potassium would volatile at 765-770celcius, C/K approximate to 6.2-9.5(wt%), which would be adsorbed by the other char particles, leading to an increasing of the content of soluble potassium and ion-exchanged potassium, promoting carbon conversion in a limited effect and a decreasing of hydroxyl functional groups on the char particles. Meanwhile, the potassium content was proportional to the migration distance, the migration distance was about 720-800 mu m at maximum under HTSM. The migration of potassium at high temperature caused the formation of liquid phase around the surface of char particles, which would prevent the contact between the gasifier agent and char particles and increase mass transfer resistance, thus preventing the increase of particle carbon conversion. In addition, no obvious liquid phase formation occurred at 800 degrees C in SFA-K, indicating that the formation of potassium -containing liquid phase and the volatilization of potassium at 800 degrees C were directly related to the carbon in the char.