Review
Chemistry, Applied
Jie Ren, Jing-Pei Cao, Xiao-Yan Zhao, Yi-Ling Liu
Summary: In recent decades, the focus of research has shifted towards producing value-added chemicals from biomass through gasification into syngas for further conversion into various products. Heterogeneous catalyst design plays a crucial role in reducing tar formation during biomass gasification, with char and char-supported catalysts emerging as effective alternatives due to their chemical inertness, cost-effectiveness, and excellent pore structures. The modification and functionalization of char through doping and metal addition show potential for enhancing the activity of these catalysts in tar reforming, highlighting the importance of sustainable fuel development and green practices.
FUEL PROCESSING TECHNOLOGY
(2021)
Article
Thermodynamics
Wen Tang, Jing-Pei Cao, Zhi-Hao Wang, Zi-Meng He, Tian-Long Liu, Ze-Ying Wang, Fei-Long Yang, Jie Ren, Xiao-Yan Zhao, Xiao-Bo Feng, Hong-Cun Bai
Summary: The study demonstrates that using acid-washed and oxidized Shengli lignite char as a carbon precursor to load cobalt nano-catalyst shows higher activity and stability in low temperature steam reforming of biomass tar, with relatively high H-2 production and low E-a value.
ENERGY CONVERSION AND MANAGEMENT
(2021)
Article
Energy & Fuels
Shuping Zhang, Yizhe Shang, Jiaxing Wang, He Chen, Yuanquan Xiong, Huiyan Zhang
Summary: A char-supported NiFe-NiFe2O4 catalyst was developed for efficient catalytic cracking of tar from biomass at a relatively low temperature. The optimized f600Fe-Ni@Char catalyst achieved a high tar conversion efficiency of 92.54% at 600 degrees C and maintained stable catalytic activity of approximately 80% after initial 3 cycles. The superior catalytic behavior of the catalyst was attributed to the protective effect of carbon nanofibers shell layer and the activation effect of NiFe-NiFe2O4 hybrid active sites. This study provides useful information for solving the bottleneck derived from tar in biomass gasification.
Review
Energy & Fuels
Andrew P. Richards, Denver Haycock, Jacob Frandsen, Thomas H. Fletcher
Summary: Accurately measuring a fuel's heating value is crucial for classification, with various empirical correlations based on primary organic elemental composition available for predicting heating values. However, correlations for coal chars and tars are lacking, and the choice of model becomes more crucial for biomass fuels and unique fuel types like propellants and explosives.
Article
Energy & Fuels
F. Cerciello, B. Apicella, C. Russo, L. Cortese, O. Senneca
Summary: The study explores the influence of pressure on the products of fast pyrolysis of a lignocellulosic biomass (Walnut Shells), showing significant changes in combustion pattern and reactivity of chars under different pressure conditions. Raman analysis indicates that graphitic order develops only at high temperature and pressure, with loss of reactivity attributed to changes in internal distribution of char components.
Article
Environmental Sciences
Chongcong Li, Hao Zhang, Xingli Gong, Yan Zhang
Summary: Tar problems are a significant barrier to the development of biomass pyrolysis technology. The use of coal chars derived from in situ pyrolysis and/or partial gasification as catalysts for tar cracking shows promise due to their low cost and easy availability. This study investigates the application of lignite chars as catalysts for biomass tar decomposition, and the results demonstrate that increasing pyrolysis temperature and char/biomass mass ratio promote tar decomposition, while water produced during biomass pyrolysis contributes to tar reforming and char gasification reactions.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2023)
Article
Chemistry, Multidisciplinary
Jiaqian Fu, Li Bai, Mingshu Chi, Xiuling Xu, Kecheng Yu, Miao Wang
Summary: In this study, the synergistic effect of Fenton pretreatment and hydrothermal carbonization on lignin was investigated. The results showed that this synergistic effect can enhance the carbon fixation rate and heating value of lignin, and improve its chemical structure and material properties.
Article
Chemistry, Applied
Ge Kong, Xin Zhang, Kejie Wang, Jing Li, Linling Zhou, Jin Wang, Xuesong Zhang, Lujia Han
Summary: Biomass gasification coupled with inline co-steam reforming (BGCSR) process was proposed to enhance H2 production and tar removal. Various gasification/pyrolysis biochar materials (G/PCMs) were used as reforming agents and co-reactants. Microalgae showed the most positive synergistic effect on H2 production and tar reduction. The presence of C[F900] resulted in the highest cumulative gas yield, H2 yield, and tar elimination synergistic effect. This study provided a novel and effective strategy for biomass valorization into H2-enriched gas while minimizing tar formation.
FUEL PROCESSING TECHNOLOGY
(2023)
Article
Energy & Fuels
Shanhui Zhao, Yunliang Zhang
Summary: In this study, the heterogeneous decomposition and steam/CO2 reforming of gasification tar over bio-char were investigated using experimental and density functional theory (DFT) approaches. The results showed that bio-char significantly enhanced the decomposition of toluene. Steam/CO2 reforming improved toluene decomposition efficiency by maintaining the activity of bio-char. DFT calculations revealed the mechanisms and energy barriers involved in the reactions, providing insights into the role of bio-char.
Article
Chemistry, Physical
Shuxiao Wang, Rui Shan, Jing Gu, Jun Zhang, Haoran Yuan, Yong Chen
Summary: The rice husk char-supported Fe and Ni catalysts showed excellent catalytic activity for removing tar and producing syngas, with a benzene conversion rate of up to 95.2%. The influence of residence time and steam-to-carbon ratio on catalytic performance was investigated, with excessive values having a negative effect on catalyst performance.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2021)
Article
Engineering, Environmental
Yen-Hau Chen, Ashak Mahmud Parvez, Max Schmid, Guenter Scheffknecht
Summary: This study evaluated the spontaneous gasification and catalytic activity of wood char in simulated sorption enhanced gasification environments, investigating the impact of hydrogen on tar-reforming performance. The results showed that spontaneous gasification during tar surrogates reforming led to the catalytic deactivation of wood char. By considering gasification-caused deactivation, the carbon conversion was used as a variable to modify the kinetic equations of the tar surrogates reforming.
CHEMICAL ENGINEERING JOURNAL
(2021)
Article
Energy & Fuels
Xinfei Chen, Xiaoqian Ma, Xiaowei Peng
Summary: The study compares Ni/Bio-char and Ni-Fe/Bio-char in CO2 reforming experiments to investigate the effect of lattice oxygen on filamentous coke resistance. Results show that Ni-Fe/Bio-char exhibits better coke resistance in CO2 reforming, but rapid consumption of lattice oxygen due to massive filamentous coke deposition is observed.
Article
Thermodynamics
Shuxiao Wang, Yuyuan Zhang, Rui Shan, Jing Gu, Haoran Yuan, Yong Chen
Summary: This paper investigates the catalytic reforming of a tar model compound (benzene) using a novel hybrid carrier catalyst in a laboratory dual-stage reactor. The results show that the catalyst has good benzene removal ability and produces gas products with high syngas content. The catalytic performance is related to surface nanoparticles and abundant active sites.
Article
Engineering, Chemical
Zhi-Hao Wang, Jing-Pei Cao, Wen Tang, Zi-Meng He, Fei-Long Yang, Ze-Ying Wang, Xiao-Yan Zhao
Summary: Recovering beneficial metal ions from industrial effluents by suitable support can efficiently prepare specific catalysts. In this study, modified lignite was used as an ion exchange material to prepare Co-Cu bimetallic catalysts for hydrogen-rich syngas production. Among all the catalysts studied, Co75Cu15/600 exhibited the best catalytic activity and stability in steam reforming reactions. The introduction of Cu contributes to the formation of Co-Cu alloy, suppressing carbon deposition and maintaining catalyst structure.
CHEMICAL ENGINEERING SCIENCE
(2023)
Article
Chemistry, Applied
Shasha Liu, Yuhui Wang, Juan Wang, Jianbin Zhou, Xun Hu, Hongqi Sun, Muhammad Asif Akhtar, Hong Zhang, Yong Huang, Shu Zhang
Summary: The effects of char-supported Ni catalysts on the decomposition of lignin model compounds were studied at different preparation temperatures, showing that higher temperature char supports can enhance the activity of the metal catalyst, leading to efficient conversion of the substrate and increased product formation. The synergistic effect of char support and Ni on BPE decomposition was demonstrated, highlighting the potential of char-supported metals as effective catalysts for biomass conversion.
FUEL PROCESSING TECHNOLOGY
(2021)
Article
Energy & Fuels
Lihua Deng, Wenda Zhang, Shaozeng Sun, Chenxi Bai, Yijun Zhao, Dongdong Feng, Linyao Zhang, Jiangquan Wu
Summary: The study focused on the application of pressurized O2/H2O combustion technology in coal-fired power generation, analyzing the thermal conversion characteristics of coal under different conditions and the relationship between char structure and reactivity.
Article
Chemistry, Physical
Yinan Shu, Linyao Zhang, Xiye Chen, Shaozeng Sun, Yudong Huang, Donald G. Truhlar
Summary: Direct dynamics by mixed quantum-classical nonadiabatic methods is crucial for understanding processes with multiple electronic states. However, the computational bottleneck lies in the electronic structure theory. In this study, we propose new algorithms that only require adiabatic potential energies and their gradients, resulting in improved computation time and accuracy compared to previous methods. This reduction in computational cost allows for longer nonadiabatic trajectories and extends the dynamics capability to new electronic structure methods.
JOURNAL OF CHEMICAL THEORY AND COMPUTATION
(2022)
Article
Thermodynamics
Lihua Deng, Wenda Zhang, Shaozeng Sun, Chenxi Bai, Yijun Zhao, Dongdong Feng, Linyao Zhang, Jiangquan Wu
Summary: This study investigated the impact of pressure on the thermal conversion characteristics of coal. The results showed that pressure can increase the yield of pyrolysis char and promote its conversion in O-2/H2O conditions.
Article
Energy & Fuels
Chenxi Bai, Wenda Zhang, Lihua Deng, Yijun Zhao, Shaozeng Sun, Dongdong Feng, Jiangquan Wu
Summary: This study investigated the effects of pressure, steam concentration, and residence time on the migration and transformation of char-N. The results showed that pressure was a significant factor in influencing NO emissions, and H2O promoted the migration of char-N to NO and the formation of N-X functional groups.
Article
Chemistry, Applied
Dawei Guo, Dongdong Feng, Yalong Zhang, Zijun Zhang, Jiabo Wu, Yijun Zhao, Shaozeng Sun
Summary: This study combines biochar adsorption with TiO2 photocatalytic technology to achieve integrated treatment of VOCs. The results show that the physical and chemical properties of the biochar-nano TiO2 cross-linked structure have been significantly improved, resulting in better removal efficiency for toluene. This study has important guiding significance for the removal of VOCs.
FUEL PROCESSING TECHNOLOGY
(2022)
Review
Chemistry, Applied
Dawei Guo, Dongdong Feng, Yu Zhang, Yalong Zhang, Yijun Zhao, Zijian Zhou, Jian Sun, Cui Quan, Guozhang Chang, Shaozeng Sun
Summary: This review summarizes the research results of carbon material-TiO2 cross-linked structure for the photocatalytic degradation of VOCs and reduction of CO2. It analyzes the impact of environmental factors on photocatalytic efficiency, the characteristics of different modification methods, and the synergistic mechanism of carbon material-TiO2.
FUEL PROCESSING TECHNOLOGY
(2022)
Article
Chemistry, Applied
Kun Chen, Wenda Zhang, Chenxi Bai, Lihua Deng, Yijun Zhao, Linyao Zhang, Dongdong Feng, Shaozeng Sun, Yukun Qin
Summary: The study found through numerical simulations that increasing H2O concentration reduces the average temperature of char particles, and O2 consumption in the boundary layer accounts for 50% of the total O2 consumption. Higher temperatures and H2O concentrations enhance competition for O2 by homogeneous reactions.
FUEL PROCESSING TECHNOLOGY
(2022)
Article
Chemistry, Physical
Linyao Zhang, Yinan Shu, Chang Xing, Xiye Chen, Shaozeng Sun, Yudong Huang, Donald G. Truhlar
Summary: The present study systematically investigates the dependence of G(0)W(0) calculations on the choice of orbitals, finding that the percentage of Hartree-Fock exchange in density functionals strongly influences the predicted molecular ionization energy and crystal band gaps. The study also suggests that global-hybrid functionals provide more accurate band gaps for semiconductors at a reasonable cost compared to widely employed methods.
JOURNAL OF CHEMICAL THEORY AND COMPUTATION
(2022)
Review
Chemistry, Applied
Lihua Deng, Yijun Zhao, Shaozeng Sun, Dongdong Feng, Wenda Zhang
Summary: This paper systematically reviews the research status and key issues of O-2/H2O combustion technology, introduces its application in pulverized coal combustion, and proposes future research directions.
FUEL PROCESSING TECHNOLOGY
(2022)
Article
Chemistry, Applied
Yu Zhang, Qi Shang, Dongdong Feng, Hongliang Sun, Fuhua Wang, Zhichao Hu, Zhenyu Cheng, Zijian Zhou, Yijun Zhao, Shaozeng Sun
Summary: The co-gasification of biomass and coal is a promising method to produce H-2-rich synthesis gas, which is of great significance for carbon-neutrality development in China.
FUEL PROCESSING TECHNOLOGY
(2022)
Article
Chemistry, Applied
Yukai Li, Dongdong Feng, Chenxi Bai, Shaozeng Sun, Yu Zhang, Yijun Zhao, Yunzhi Li, Feng Zhang, Guozhang Chang, Yukun Qin
Summary: This study simulated the local location of the horizontal cyclone furnace using a small high-temperature test bench and investigated the influence of various fluxing agents on the melting of MSWI fly ash. The results showed that controlling the content and ratio of different fluxing agents is important to obtain low melting-point minerals and high glass phase concentration.
FUEL PROCESSING TECHNOLOGY
(2022)
Article
Chemistry, Physical
Hongliang Sun, Dongdong Feng, Yu Zhang, Shaozeng Sun, Yijun Zhao, Feng Zhang
Summary: This paper investigates the coke accumulation characteristics in catalytic tar reforming using different K and Ca-loaded biochar catalysts. The results indicate that K-loaded biochar exhibits a higher tar conversion capacity, while H-form biochar has a lower tar removal efficiency. The loading of K/Ca affects the growth structure of the coke, with K-loaded biochar retaining a higher micropore area and experiencing a smaller increase in average pore size. Furthermore, the loading of K promotes the dehydrogenation of tar components, while only K catalyzes the deoxygenation of tar components. These findings are important for improving the efficiency and selectivity of tar reforming.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Energy & Fuels
Hongliang Sun, Dongdong Feng, Yu Zhang, Shaozeng Sun, Yijun Zhao, Feng Zhang
Summary: This study investigates the regeneration of catalytic activity of biochar through partial oxidation for biomass tar reforming. The results demonstrate that oxidative regeneration effectively recovers the catalytic activity of biochar and promotes the production of methane and hydrogen. The regenerated biochar exhibits increased external surface area, microporous area, and abundance of oxygen-containing structures, compared to the deactivated biochar. The optimal regeneration condition for deactivated biochar is found to be 9 minutes with 0.4% oxygen concentration.
Article
Chemistry, Applied
Chenxi Bai, Yu Zhang, Wenda Zhang, Kun Chen, Lihua Deng, Yijun Zhao, Shaozeng Sun, Dongdong Feng, Jiangquan Wu
Summary: Pressurization and H2O were found to promote char conversion and facilitate the formation of carbon-oxygen bonds on the char surface. Pressure mainly affected the consumption and generation of micropores, while H2O had no selective effect on the pore structure. At low pressure and low H2O concentration, pressurization and H2O could promote the formation of C(O) on the char surface, but the reactivity of char decreased and then increased with increasing pressure and H2O concentration.
FUEL PROCESSING TECHNOLOGY
(2022)
Article
Chemistry, Applied
Shizhang Wang, Linhan Dong, Dongdong Feng, Yu Zhang, Zijun Zhang, Dawei Guo, Wei Zhang, Kan Wu, Yijun Zhao, Shaozeng Sun
Summary: The global greenhouse effect is a serious issue, and many countries have reached a consensus on carbon neutrality. The high-value utilization of agricultural waste is of great significance for reducing carbon emissions, and the use of agricultural waste to produce biochar products has promising applications. This study focuses on preparing high-performance rice husk-derived biochar using different methods, and obtains biochar with varying surface areas and pore structures. This provides a theoretical basis and new ideas for the construction of functional rice husk-derived biochar.
FUEL PROCESSING TECHNOLOGY
(2022)