Insight into the Ex Situ Catalytic Pyrolysis of Biomass over Char Supported Metals Catalyst: Syngas Production and Tar Decomposition

Ex situ catalytic pyrolysis of biomass using char-supported nanoparticles metals (Fe and Ni) catalyst for syngas production and tar decomposition was investigated. The characterizations of fresh Fe-Ni/char catalysts were determined by TGA, SEM–EDS, Brunauer–Emmett–Teller (BET), and XPS. The results indicated that nanoparticles metal substances (Fe and Ni) successfully impregnated into the char support and increased the thermal stability of Fe-Ni/char. Fe-Ni/char catalyst exhibited relatively superior catalytic performance, where the syngas yield and the molar ratio of H2/CO were 0.91 Nm3/kg biomass and 1.64, respectively. Moreover, the lowest tar yield (43.21 g/kg biomass) and the highest tar catalytic conversion efficiency (84.97 wt.%) were also obtained under the condition of Ni/char. Ultimate analysis and GC–MS were employed to analyze the characterization of tar, and the results indicated that the percentage of aromatic hydrocarbons appreciably increased with the significantly decrease in oxygenated compounds and nitrogenous compounds, especially in Fe-Ni/char catalyst, when compared with no catalyst pyrolysis. After catalytic pyrolysis, XPS was employed to investigate the surface valence states of the characteristic elements in the catalysts. The results indicated that the metallic oxides (MexOy) were reduced to metallic Me0 as active sites for tar catalytic pyrolysis. The main reactions pathway involved during ex situ catalytic pyrolysis of biomass based on char-supported catalyst was proposed. These findings indicate that char has the potential to be used as an efficient and low-cost catalyst toward biomass pyrolysis for syngas production and tar decomposition.

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Regulating light olefins or aromatics production in ex-situ catalytic pyrolysis of biomass by engineering the structure of tin modified ZSM-5 catalyst

Bioresource Technology ◽

10.1016/j.biortech.2021.124975 ◽

2021 ◽

pp. 124975

Author(s):

Jingyuan Shang ◽

Guangbin Fu ◽

Zhenping Cai ◽

Xiang Feng ◽

Yongxiao Tuo ◽

...

Keyword(s):

Catalytic Pyrolysis ◽

Ex Situ ◽

Light Olefins ◽

Pyrolysis Of Biomass

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Is it possible to increase the oil yield of catalytic pyrolysis of biomass? A study using commercially-available acid and basic catalysts in ex-situ and in-situ modus

Journal of Analytical and Applied Pyrolysis ◽

10.1016/j.jaap.2018.11.012 ◽

2019 ◽

Vol 137 ◽

pp. 77-85 ◽

Cited By ~ 8

Author(s):

Daniele Castello ◽

Songbo He ◽

M. Pilar Ruiz ◽

Roel J.M. Westerhof ◽

Hero Jan Heeres ◽

...

Keyword(s):

Catalytic Pyrolysis ◽

Ex Situ ◽

Oil Yield ◽

Basic Catalysts ◽

Pyrolysis Of Biomass

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Molecular Dynamic Simulation of Hydrogen Production by Catalytic Gasification of Key Intermediates of Biomass in Supercritical Water

Journal of Energy Resources Technology ◽

10.1115/1.4037814 ◽

2017 ◽

Vol 140 (4) ◽

Cited By ~ 27

Author(s):

Hui Jin ◽

Bin Chen ◽

Xiao Zhao ◽

Changqing Cao

Keyword(s):

Supercritical Water ◽

Active Sites ◽

Density Functional ◽

Free Carbon ◽

Ni Catalyst ◽

Catalytic Gasification ◽

Syngas Production ◽

Reactor Optimization ◽

Cu Catalyst ◽

Microscopic Reaction

Supercritical water gasification (SCWG) is an efficient and clean conversion of biomass due to the unique chemical and physical properties. Anthracene and furfural are the key intermediates in SCWG, and their microscopic reaction mechanism in supercritical water may provide information for reactor optimization and selection of optimal operating condition. Density functional theory (DFT) and reactive empirical force fields (ReaxFF) were combined to investigate the molecular dynamics of catalytic gasification of anthracene and furfural. The simulation results showed that Cu and Ni obviously increased the production of H radicals, therefore the substance SCWG process. Ni catalyst decreased the production of H2 with the residence time of 500 ps while significantly increased CO production and finally increased the syngas production. Ni catalyst was proved to decrease the free carbon production to prohibit the carbon deposition on the surface of active sites; meanwhile, Cu catalyst increased the production of free carbon.

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Effect of acidity and manner of addition of HZSM-5 catalyst on the aromatic products during catalytic upgrading of biomass pyrolysis

BioResources ◽

10.15376/biores.12.4.8286-8305 ◽

2017 ◽

Vol 12 (4) ◽

pp. 8286-8305

Author(s):

Yunwu Zheng ◽

Lei Tao ◽

Xiaoqin Yang ◽

Yuanbo Huang ◽

Can Liu ◽

...

Keyword(s):

Aromatic Hydrocarbons ◽

Aromatic Compounds ◽

Catalytic Pyrolysis ◽

Calorific Value ◽

Ex Situ ◽

Average Pore ◽

Polycyclic Aromatic ◽

Hydrocarbon Yield ◽

Pyrolysis Of Biomass

To investigate the effects of acidity on aromatic yield and selectivity during the catalytic pyrolysis of biomass, the silica to alumina ratio (SAR), as well as the amount and addition method of HZSM-5 catalyst were varied. The results showed that with an increase in the SAR, the pore volume was reduced, the average pore diameter of the HZSM-5 catalyst increased, and the total acidity and catalytic activity decreased. Meanwhile, the increase in acidity led to an increased non-condensable gases yield, which was associated with a decrease in the bio-oil yield. The calorific value and moisture content increased, and the ability of deoxygenation was enhanced. The single ring aromatic hydrocarbons (BTXE) content increased, and the polycyclic aromatic hydrocarbons (2-ring, 3-ring) content decreased noticeably. The selectivity of BTXE decreased substantially from 69 wt.% to 6.85 wt.%, while the selectivity of naphthalene and its derivatives increased remarkably, as the SAR increased. Additionally, the acidity increased the selectivity of unsubstituted aromatic compounds, but decreased the selectivity of substituted aromatic compounds. Moreover, ex situ catalytic pyrolysis more effectively enhanced the aromatic hydrocarbon yield and selectivity (69 wt.%) compared with in situ catalytic pyrolysis (27.51 wt.%), and in situ catalytic pyrolysis generated more polyaromatics and solid residue.

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From Douglas fir to renewable H2-enriched syngas via ex situ catalytic pyrolysis over metal nanoparticles–nanocellulose derived carbon catalysts

Sustainable Energy & Fuels ◽

10.1039/c9se00860h ◽

2020 ◽

Vol 4 (3) ◽

pp. 1084-1087 ◽

Cited By ~ 1

Author(s):

Yayun Zhang ◽

Dengle Duan ◽

Hanwu Lei ◽

Chenxi Wang ◽

Moriko Qian ◽

...

Keyword(s):

Metal Nanoparticles ◽

Catalytic Pyrolysis ◽

Douglas Fir ◽

Optimal Performance ◽

Ex Situ ◽

Carbon Catalyst ◽

Carbon Catalysts ◽

Pyrolysis Of Biomass

A carbon catalyst, which was derived from nanocellulose (NC) and doped with uniform sized and well dispersed metal nanoparticles, showed optimal performance for the generation of H2-enriched (67.4 vol%) syngas from the catalytic pyrolysis of biomass.

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Species transport and reaction characteristics between gas and solid phases for ex-situ catalytic pyrolysis of biomass

Energy ◽

10.1016/j.energy.2021.120212 ◽

2021 ◽

Vol 225 ◽

pp. 120212

Author(s):

Yuchun Zhang ◽

Peng Fu ◽

Weiming Yi ◽

Zhihe Li ◽

Zhiyu Li ◽

...

Keyword(s):

Catalytic Pyrolysis ◽

Ex Situ ◽

Species Transport ◽

Reaction Characteristics ◽

Solid Phases ◽

Pyrolysis Of Biomass

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Syngas production by catalytic pyrolysis of rice straw over modified Ni-based catalyst

BioResources ◽

10.15376/biores.15.2.2293-2309 ◽

2020 ◽

Vol 15 (2) ◽

pp. 2293-2309

Author(s):

Kui Lan ◽

Zhenhua Qin ◽

Zeshan Li ◽

Rui Hu ◽

Xianzhou Xu ◽

...

Keyword(s):

Rice Straw ◽

Catalytic Pyrolysis ◽

Fixed Bed ◽

Dry Weight ◽

Catalytic Performance ◽

Molar Ratio ◽

Active Components ◽

X Ray ◽

Syngas Production ◽

The Stability

Ni-xLa/Al2O3-MgO-sawdust char catalysts were prepared by modifying the Ni/Al2O3 catalyst from two aspects of support and active components. The effect of Al2O3, MgO, sawdust char molar ratio, and La content of catalysts on syngas (H2 + CO) production in the catalytic pyrolysis of rice straw was investigated in a horizontal ﬁxed-bed quartz tube reactor. Furthermore, the stability of catalysts with the optimum catalytic performance was tested and compared with that of the Ni/Al2O3 catalysts. X-ray diffraction, X-ray ﬂuorescence, ﬁeld emission scanning electron microscopy, energy disperse X-ray, and Brunauer-Emmett-Teller analyses were applied to understand the physiochemical properties of the supports and catalysts. The study revealed that the supports were composed of many irregular flaky particles and thus formed many pores. Moreover, the addition of La decreased the particle size of NiAl2O4 and increased the active metal surface of the Ni/Al2O3-MgO-sawdust catalysts. When the molar ratio of Al2O3, MgO, and sawdust char was 1:1:1 and the La content was 10 wt% (dry weight basis), the catalysts presented the highest syngas concentration of 78.9 vol% and the most stable performance during the catalytic pyrolysis process.

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