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

Abstract

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.

Integrating Nanomaterial and High‐Performance Fuzzy‐Based Machine Learning Approach for Green Energy Conversion

“…In catalytic process, the catalyst and feedstock materials are mixed together and kept inside the reactor for catalytic reforming and cracking. Various types of catalysts including nickel-based, metal-based, alkalibased, zeolite catalysts, and carbon-supported catalysts are used in various processes for the production of higher amount of volatiles [25]. For the catalytic pyrolysis conversion of wood-based biomass materials, ZSM-5 zeolite is the most commonly utilized catalysts.…”

Preparation of Ni-La/Al2O3-CeO2-Bamboo Charcoal Catalyst and its Application in Co-pyrolysis of Straw and Plastic for Hydrogen Production

“…The catalyst showed high tar conversion efficiency of 77.1% for RHC, 82.7% for K-RHC, 90.6% for Cu-RHC and 92.6% for Fe-RHC at 800 °C. The char and char-supported catalyst promote the conversion of larger polycyclic aromatic hydrocarbons into lighter tar compounds, which are further catalyzed and converted into small molecular gas compounds [25][26][27][28]. Five Ni/C catalysts with different Ni content were tested [29], the sample with 13.2wt% Ni showed the highest conversion of CH4 for dry reforming of methane at 800°C.…”

State of the Art and Perspectives in Catalytic Conversion Mechanism of Biomass to Bio-aromatics

“…Currently, researchers have developed a variety of routes for the preparation of bio-aromatics from biomass, such as gasification and pyrolysis. , The biomass gasification focuses on the conversion of biomass syngas (CO + H 2 ) to bio-aromatics through olefins or methanol/dimethyl ether, which consists of the biomass Fischer–Tropsch synthesis (BFTS) route and biomass methanol to bio-aromatics (BMTA) route. − Compared to biomass gasification, biomass pyrolysis can produce bio-aromatics in a relatively environmentally friendly manner, creating a certain amount of liquid fuel, called bio-oil, which consists of alcohols, phenols, ethers, and hydrocarbons. Then, the bio-oil was further converted into high-quality bio-aromatics .…”