文献类型：期刊文献

英文题名：The evolution of catalytically active calcium catalyst during steam gasification of lignite char

作者：Zhang, Jie[1,2];Tang, Jia[3];Liu, Lijuan[4];Wang, Jie[5]

机构：[1]Univ Shanghai Sci & Technol, Sch Energy & Power Engn, Shanghai 200093, Peoples R China;[2]Shanghai Key Lab Multiphase Flow & Heat Transfer, Shanghai 200093, Peoples R China;[3]Ningde Amperex Technol Ltd, 1 Xingang Rd, Ningde 35200, Fujian, Peoples R China;[4]Zhengzhou Univ, Sch Phys & Microelect, 100 Sci Ave, Zhengzhou 450001, Henan, Peoples R China;[5]East China Univ Sci & Technol, Dept Chem Engn Energy, 130 Meilong Rd, Shanghai 200237, Peoples R China

年份：2021

卷号：172

起止页码：162

外文期刊名：CARBON

收录：;EI(收录号：20204209358122);WOS:【SCI-EXPANDED(收录号:WOS:000600422000001)】；

基金：This work is funded by Natural Science Cultivation Fund and the Startup Fund at the University of Shanghai for Science and Technology (Grant No. ZR20PY05 and 1D-19-301-005). We thank Dr. Anthony De Girolamo from Monash University for his linguistic assistance during the preparation of this manuscript.

语种：英文

外文关键词：Lignite char; Catalytic gasification; Calcium catalyst; Potassium catalyst; Catalytic mechanism

摘要：Coal or coal char/pyrocarbon gasification is a viable way to produce cheaper hydrogen. The gasification of three different lignites and their pretreated samples showed that either the intrinsic calcium in lignite or the extrinsic calcium added by ion exchange had high catalytic activity. It was proven that most of the calcium in the lignite was organically associated, which was mainly bound to carboxyl groups and highly dispersed at an atomic level. Furthermore, Yuxi lignite was demineralized to investigate the catalytic characteristics of calcium and potassium catalysts on steam gasification. The changes of gasification rate, gas compositions and oxygen chemisorption capacity with carbon conversion hinted that the catalytic mechanism of calcium was different from that of potassium. X-ray absorption near edge structure (XANES) analysis revealed that carboxyl-bound calcium was the active form of the catalyst, and the deactivation of the calcium catalyst in the gasification process was due to the transformation of carboxylbound calcium to other chemical forms. The organically bound calcium also led to the porous char structures at the early gasification stage, which improved the catalytic activity. (C) 2020 Elsevier Ltd. All rights reserved.