Article
Engineering, Chemical
Dezhi Chen, Xinyu Ning, Wen Tang, Jun Xu, Kai Xu, Limo He, Hengda Han, Sheng Su, Long Jiang, Yi Wang, Song Hu, Jun Xiang
Summary: This study utilized micro-Raman spectroscopy to investigate the chemical structures of pyrolytic chars prepared from 32 kinds of Chinese coals, finding that the aromatization degree is the key distinguishable factor for chars prepared from coals of different ranks. A comprehensive coal property index was proposed to predict the chemical structure of pyrolytic char effectively.
Article
Chemistry, Applied
Lin Li, Shuai Tong, Lunbo Duan, Changsui Zhao, Zhipeng Shi
Summary: By comparing chars produced under different atmospheres, it was found that the pore structure and specific surface area of chars are significantly affected by the gasification environment, while the presence of chemical groups has a minor impact on the chars. The best gasification reactivities were obtained on the chars produced under 50%CO2/50%N2 and 50%H2O/50%N2 atmospheres, largely influenced by the porosity of the chars.
FUEL PROCESSING TECHNOLOGY
(2021)
Article
Engineering, Environmental
Song Qianshi, Wang Xiaohan, Li Haowen, Yang Zixin, Ye Yue, Huo Jiepeng
Summary: The study found that the self-developed char reactivity model accurately predicted the reaction rate of char samples under different gasification temperatures, providing a valuable reference for predicting char gasification reaction rate.
CHEMICAL ENGINEERING JOURNAL
(2022)
Article
Energy & Fuels
Yangang Mei, Zhiqing Wang, Shengjian Zhang, Yitian Fang
Summary: Catalytic gasification with alkali addition is a novel gasification technology, where the catalytic effect is attributed to the activation of CO2 on the alkali surface. A new gasification mechanism is proposed, providing new insight for the process of catalytic gasification.
Article
Energy & Fuels
Muhammad Irfan, Aimin Li, Lei Zhang, Jianhua Liu, Tanzeel Javaid Aini Farooqi, Muhammad Javid, Abdul Rauf
Summary: In this study, waste tire-derived char was used as a support material for developing Ni-Fe-based catalysts, which significantly enhanced the performance in wet MSW catalytic conversion by boosting H-2 concentration, dry gas yield, and H-2 yield while reducing tar content. The tar analysis revealed a significant transformation in chemical composition with the application of catalysts. This work highlights the potential of utilizing waste tire-derived char as an effective and inexpensive support material for developing catalysts for MSW conversion.
INTERNATIONAL JOURNAL OF ENERGY RESEARCH
(2022)
Article
Engineering, Environmental
Kagiso Bikane, Jie Yu, Ravi Shankar, Xiangyi Long, Nigel Paterson, Marcos Millan
Summary: This study investigates the gasification kinetics of Morupule coal in atmospheric pressure CO2 and the structural evolution of residual chars. The research shows that gasification reaction rates are high, with little impact on the bulk chemical structure of chars but significant changes in surface chemistry. Residual chars from gasification experiments exhibit lower combustion reactivity compared to chars produced under inert pyrolysis conditions.
CHEMICAL ENGINEERING JOURNAL
(2021)
Article
Engineering, Chemical
Mingyuan Wang, Wen Fu, Haibin Wang, Junzhe Cai, Jiayu Zhang, Zhicheng Tao, Li Li, Xuefeng Wang, Ye Hua, Xiaowei Bai
Summary: This study used multiple analysis techniques to investigate the structure and pyrolysis reactions of nine typical coals and chars from Xinjiang. The results showed that the reduction degree of CO structures in coal during coalification is related to the Vdaf content. Condensation of aromatic rings during coalification led to a decrease in CO structures, while the contents of cross-linking and substitution structures persistently decreased relative to the large aromatic ring structures. Coal type influenced char and tar yields, particularly the yields of alkanes and phenols in tar. During pyrolysis, the relative content of large aromatic ring structures in coal remained stable, while the relative content of small aromatic ring structures declined, suggesting that small aromatic rings might transform into tar, resulting in a high selectivity of phenolic products in tar.
CANADIAN JOURNAL OF CHEMICAL ENGINEERING
(2023)
Article
Energy & Fuels
Yun Liu, Yuan Zhang, Yu-qing Zhang, Lian-sheng Chen, Hai-ying Li, Hui-min Liu
Summary: The study investigated the effects of pyrolysis heating rate on the char structure and CO2 gasification reactivity of energy crops, revealing that bio-char obtained at a rapid heating rate had more structural defects and carbon crystallite imperfections, leading to higher gasification reactivity. However, this also resulted in a decrease in crystallization size, graphitization, and aromatization degree.
Article
Thermodynamics
Ruochen Wu, Jacob Beutler, Larry L. Baxter
Summary: This investigation examines the trends in biomass char diameter during gasification using continuous particle size data and a theoretical model to describe the variations. The model captures the qualitative and most of the quantitative variation in the data.
Article
Crystallography
Yanshan Yin, Zihua Wu, Jianhang Tao, Caiwen Qi, Wei Zhang, Shan Cheng
Summary: This paper investigates the evolution of the chemical structure of coal char during pyrolysis. The results show that the degree of order and the content of graphite-like microcrystalline carbon in coal char vary with pyrolysis temperatures. The relative content of C=O and COOH in coal char decreases with increasing temperature, indicating an increase in the degree of order at higher temperatures.
Article
Energy & Fuels
Jiangyong He, Chong Zou, Junxue Zhao, Jiale Xi, Yuan She, Mengmeng Ren, Yufen Xu
Summary: This study investigates the variability in in situ Raman spectroscopy for determining the chemical structure of chars. The study explores the rationality of Raman's original peak spectrum fitting method, the influence of objective lens magnification, particle size, and number of measurements on peak shape and characteristic parameters.
Article
Energy & Fuels
Rafal Morga, Barbara Bielowicz
Summary: This study characterizes and compares the microstructural features of different morphotypes in coal char obtained through gasification, revealing similarities and differences in their microstructural properties. Optical microscopy and Raman spectroscopy were used for analysis.
Article
Chemistry, Multidisciplinary
Qinghua Guo, Yuchen Huang, Qing He, Yan Gong, Guangsuo Yu
Summary: The study found that coal char prepared by wet impregnation had higher reactivity, and the optimal addition method is wet impregnation with a 2% catalyst. The iron-based catalyst can accelerate the gasification rate and provide higher catalytic activity.
Article
Energy & Fuels
Bo Wang, Fanfan Xu, Xin Wang, Jun Li, Yongyi Song, Yingyun Qiao, Yuanyu Tian
Summary: This study provides a comprehensive comparative investigation on feedstock pyrolysis and char gasification performance of typical forestry biomass from Northeast Asia. The results showed that different forestry biomass has close thermal decomposition characteristics, and Salicaceae char has better gasification performance than Pinaceae char due to its high AAEMs content.
Article
Energy & Fuels
Bo Wang, Fanfan Xu, Xin Wang, Jun Li, Yongyi Song, Yingyun Qiao, Yuanyu Tian
Summary: The present study provides a comprehensive comparative investigation on the feedstock pyrolysis and char gasification performance of typical forestry biomass from Northeast Asia. The results show that different forestry biomass has similar thermal decomposition characteristics, and the performance of Salicaceae is better than that of Pinaceae in terms of pyrolysis and char gasification.
Article
Chemistry, Analytical
Guanshuai Zhang, Shanjian Liu, Dongmei Bi, Zhisen He, Jia Liu, Yinjiao Liu
Summary: Hydrogen peroxide pretreatment was applied for fast pyrolysis of corn stalks, and it was found that the pretreatment effectively promoted lignin depolymerization and decreased the reaction activation energy. The pretreatment also increased the cellulose content and removed alkali and alkaline earth metals from the biomass. The pH of the hydrogen peroxide solution affected the removal of lignin and ash by the pretreatment, and the composition of bio-oil changed significantly, with a significant increase in the relative content of levoglucosan after pretreatment.
JOURNAL OF ANALYTICAL AND APPLIED PYROLYSIS
(2024)
