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Young-kwon Park - One of the best experts on this subject based on the ideXlab platform.
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Catalytic Pyrolysis of Polyethylene Terephthalate Over Desilicated Beta.
Journal of nanoscience and nanotechnology, 2020Co-Authors: Heejin Lee, Sangchul Jung, Young-min Kim, Young-kwon ParkAbstract:The desilication effect of Beta on the Catalytic Pyrolysis of polyethylene terephthalate (PET) was investigated in this study. Compared to parent Beta, desilicated Beta revealed the higher aromatics formation efficiency due to its larger pore size allowing the efficient diffusion of PET Pyrolysis intermediates to the catalyst pore. Compared to the in-situ Catalytic Pyrolysis, ex-situ Catalytic PET Pyrolysis over desilicated Beta produced a larger amount of aromatics. The desilicated catalyst could be re-used without catalyst regeneration due to the small extent of catalyst deactivation.
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Catalytic Pyrolysis of Tetra Pak over Acidic Catalysts
Catalysts, 2020Co-Authors: Muhammad Zain Siddiqui, Young-kwon Park, Young-min Kim, Tae Uk Han, Seungdo KimAbstract:The thermal and Catalytic Pyrolysis of two kinds of Tetra Pak waste (TP-1 and TP-2) over three different acidic catalysts—HZSM-5(SiO2/Al2O3, 30), HBeta (38), and Al-MCM-41(20)—were investigated in this study. Tetra Pak (TP) wastes consist of composite material comprising kraft paper, polyethylene (PE) film, and aluminum foil. Thermal decomposition behaviors during the Pyrolysis of TPs were monitored using a thermogravimetric (TG) analyzer and tandem micro reactor-gas chromatography/mass spectrometry (TMR-GC/MS). Neither the interaction between the non-Catalytic Pyrolysis intermediates of kraft paper and PE, nor the effect of aluminum foil have been monitored during the non-Catalytic TG analysis of TPs. The maximum decomposition temperatures of PE in TP-1 shifted from 465 °C to 432 °C by HBeta(38), 439 °C by HZSM-5(30), and 449 °C by Al-MCM-41(20), respectively. The results of the TMR-GC/MS analysis indicate that the non-Catalytic Pyrolysis of TPs results in the formation of large amounts of furans and heavy hydrocarbons and they are converted efficiently to aromatic hydrocarbons over the acidic catalysts. Among the three catalysts, HZSM-5(30) produced the largest amount of aromatic hydrocarbons, followed by HBeta(38) and Al-MCM-41(20) owing to their different acidity and pore size. Compared to TP-1, TP-2 produced a larger amount of aromatic hydrocarbons via Catalytic Pyrolysis because of its relatively larger PE content. The synergistic formation of aromatic hydrocarbons was also enhanced during the Catalytic Pyrolysis of TPs due to the effective role of PE as hydrogen donor to kraft paper. In terms of their Catalytic effectiveness, HZSM-5(30) had a longer lifetime than HBeta(38).
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Recent advances in the Catalytic Pyrolysis of microalgae
Catalysis Today, 2020Co-Authors: Jechan Lee, Eilhann E. Kwon, Young-kwon ParkAbstract:Abstract The Catalytic Pyrolysis of microalgae offers a strategic means of increasing the value of pyrogenic products. Microalgae are a promising Pyrolysis feedstock. This review summarizes the state-of-the-art Catalytic Pyrolysis processes to form bio-oil with a high proportion of aromatic compounds. The focus is on the current knowledge of the mechanisms to form aromatic hydrocarbon species from the Catalytic Pyrolysis of microalgae. In addition, that the effects of the reaction conditions and catalyst selection on the yield and composition of microalgal bio-oil are reviewed. The information shows that the catalyst and feedstock properties are closely associated with the formation of desired aromatic compounds. In addition, this review defines the technical challenges that need to be overcome and suggests future research for the further development of Catalytic Pyrolysis technologies for the production of aromatics from microalgae.
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CO2-cofeeding Catalytic Pyrolysis of macadamia nutshell
Journal of CO2 Utilization, 2020Co-Authors: Sungyup Jung, Young-kwon Park, Dohee Kwon, Yiu Fai Tsang, Eilhann E. KwonAbstract:Abstract Here in this study, we laid great stress on a development of sustainable waste-to-energy (WtE) platform via CO2-cofeeding Catalytic Pyrolysis of macadamia nutshell (MNS) at mild temperature region. To this end, one-stage and two-stage (non-Catalytic/Catalytic) Pyrolysis of MNS was performed to establish the fundamental relationship of temperature effect on syngas formation. The formation of gaseous pyrolysates was substantially enhanced when two-stage Pyrolysis of MNS was applied, and second heating zone isothermally ran at 700 °C. Such the enhanced generation of gaseous pyrolysates from two-stage MNS Pyrolysis of MNS was likely due to temperature-driven cracking of volatile organic compounds (VOCs). Also, Catalytic two-stage Pyrolysis of MNS was performed at lower isothermal running temperature (500 °C) over Ni/SiO2 and Co/SiO2. The enhanced formation of syngas (H2 and CO) was observed from Catalytic Pyrolysis of MNS. Therefore, Pyrolysis of MNS over Ni/SiO2 or Co/SiO2 could be a reliable platform for enhancing syngas formation at mild temperature (≤ 500 °C) under CO2 environment. In addition, all experimental findings suggested that the use of CO2 is beneficial in the WtE platform, and the use of CO2 could be a practical climate change mitigation measure.
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effective use of aluminum plastic laminate as a feedstock for Catalytic Pyrolysis over micro and mesoporous catalysts
Journal of Cleaner Production, 2019Co-Authors: Muhammad Zain Siddiqui, Young-kwon Park, Yejin Kang, Atsushi WatanabeAbstract:Abstract Thermal and Catalytic Pyrolysis of aluminum plastic laminate over zeolite catalysts were performed to produce high quality oil. Thermogravimetric analysis of aluminum plastic laminate indicated that the decomposition kinetics of aluminum plastic laminate were changed by interactions between the polymer components during the thermogravimetric analysis of aluminum plastic laminate. The effects of aluminum foil on the aluminum plastic laminate decomposition kinetics were negligible. The Catalytic Pyrolysis of aluminum plastic laminate over the acid catalysts using tandem-micro reactor-gas chromatography/mass spectrometry produced large amounts of aromatics due to the properties of the main polymers, polyethylene and poly (ethylene terephthalate), in aluminum plastic laminate. Among three catalysts, HZSM-5 (SiO2/Al2O3, 23), HY(30), and Al-MCM-41 (20), HZSM-5 (23) had the highest efficiency on aromatics production followed by HY(30) and Al-MCM-41 (20). Co-feeding aluminum plastic laminate to the Catalytic Pyrolysis of paper over HZSM-5 (23) and HY(30) was also effective on aromatics production, highlighting the potential use of aluminum plastic laminate to enhance the synergistic aromatics formation during the Catalytic Pyrolysis of biomass.
Xianghai Meng - One of the best experts on this subject based on the ideXlab platform.
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Thermodynamic equilibrium distribution of light olefins in Catalytic Pyrolysis
Applied Catalysis A: General, 2016Co-Authors: Rui Zhang, Zhichang Liu, Zhixi Wang, Haiyan Liu, Guili Liu, Xianghai MengAbstract:Abstract Catalytic Pyrolysis is a promising technology to produce light olefins. Gibbs free-energy minimization method was used to study the thermodynamic equilibrium distribution of olefins in Catalytic Pyrolysis with Aspen Plus software. The result showed that olefin systems with different carbon numbers demonstrated a similar thermodynamic equilibrium distribution. The ethene equilibrium composition increased with increasing reaction temperature and decreased with increasing total hydrocarbon pressure. By contrast, the propene equilibrium composition reached a maximum of 40 wt% at 850–950 K under 0.1 MPa. Ethene yield and propene yield of thermodynamic equilibrium, Catalytic Pyrolysis and thermal Pyrolysis were compared. The use of catalyst greatly increased the yields of ethene and propene, but the yields were still lower than the equilibrium data. Catalytic Pyrolysis was carried out in the interaction zone where both Catalytic conversion and thermal conversion were important. Propene yield was close to ethene yield at about 950 K from the thermodynamic view. Given the shape-selective effect of the catalyst on branched olefins with large carbon number, the equilibrium carbon number distribution of olefins possibly shifted from large carbon numbers to low carbon numbers, resulting in enhanced ethene and propene yields.
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hydrogen balance for Catalytic Pyrolysis of atmospheric residue
Fuel Processing Technology, 2009Co-Authors: Xianghai Meng, Jinse Gao, Zhichang LiuAbstract:Abstract The Catalytic Pyrolysis of atmospheric residue over the commercial Catalytic Pyrolysis process catalyst (Al 2 O 3 /Fe 2 O 3 /Na 2 O (46.3, 0.27 and 0.04 wt.%, respectively)) was investigated in a confined fluidized bed reactor. The yield of light olefins was above 37 wt.% at reaction temperature above 600 °C and it reached a maximum of 47 wt.% at 660 °C. The main components in light olefins were ethylene and propylene, and those in liquid samples were aromatics. The main components in light alkanes were propane and i-butane at low reaction temperature (600 °C), and those were methane and ethane at high reaction temperature (700 °C). The hydrogen content of light olefins was about 14.27 wt.%, that of light alkanes was above 18.5 wt.%, that of gasoline was below 12.5 wt.%, and that of diesel was below 7.8 wt.%. The percentage of the hydrogen in light alkanes to total hydrogen was above 29% and that in light olefins was above 40%. The effective utilization ratio of hydrogen decreased from 66.60% at 600 °C to 61.44% at 700 °C.
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Seven-lump kinetic model for Catalytic Pyrolysis of heavy oil
Catalysis Communications, 2007Co-Authors: Xianghai Meng, Jinsen GaoAbstract:Abstract A 7-lump kinetic model is proposed to describe the Catalytic Pyrolysis of heavy oil. The kinetic model contains 15 kinetic constants and one for catalyst deactivation. The experimental data were obtained in a confined fluidized bed reactor. The kinetic constants were estimated by a special program compiled based on the Marquardt’s algorithm. The apparent activation energies were calculated according to the Arrhenius equation. This model fits the experimental data well. The prediction shows that Catalytic Pyrolysis of Chinese Daqing atmospheric residue should be conducted at low space velocity to produce much ethene and at space velocity around 15 h −1 to produce much propene and butene.
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Production of Light Olefins by Catalytic Pyrolysis of Heavy Oil
Petroleum Science and Technology, 2006Co-Authors: Xianghai Meng, Jinsen GaoAbstract:Catalytic Pyrolysis is a promising technology for the production of light olefins. In this article, current advances in Catalytic Pyrolysis with respect to Pyrolysis catalysts, technologies and reaction mechanisms are summarized. An experimental laboratory method, based on a confined fluidized bed reactor, has been used to study Catalytic Pyrolysis of Chinese Daqing atmospheric residue over three different catalysts: LCM-5, CEP-1, and RSCC-29. Analysis of pyrolyzed gases shows that product yields are strongly dependent on catalyst type. The optimal operating conditions vary with catalyst type, but in each case, the yields of total light olefins show maxima with increasing temperature. Pyrolyzed liquids are primarily aromatic components, indicating that the degree of Catalytic Pyrolysis is very deep. Hydrogen balance analysis shows that the Catalytic Pyrolysis of heavy oil is capable of producing light olefins with high hydrogen contents.
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Reaction behaviors and mechanisms of Catalytic Pyrolysis of C4 hydrocarbons
Chemical Engineering Journal, 2006Co-Authors: Jinsen Gao, Xianghai MengAbstract:Catalytic Pyrolysis of C4 hydrocarbons over a modified ZSM-5 zeolite was investigated in a fixed bed reactor. The effects of reaction temperature and dilution ratio on product yields and distribution were studied, ethylene yield goes up monotonously with the enhancement of reaction temperature; meanwhile, propylene yield shows a maximum at about 580 °C. As dilution ratio increases, the yield of propylene increases until a dilution ratio of 2.0 is reached, and then changes slightly, and that of ethylene passes through a maximum at about 2.0. For Catalytic Pyrolysis of n-butylene, two reaction pathways have been proposed, the monomolecular reaction mechanism and the bimolecular reaction mechanism. With the analysis of these two reaction pathways and the experimental data, a conclusion is drawn that Catalytic Pyrolysis of n-butylene follows the bimolecular reaction mechanism. According to this mechanism, n-butylene Catalytic Pyrolysis involves two successive reaction steps: the dimerization of n-butylene and the cracking of the dimers.
Jong-ki Jeon - One of the best experts on this subject based on the ideXlab platform.
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Catalytic Pyrolysis of wood polymer composites over hierarchical mesoporous zeolites
Energy Conversion and Management, 2019Co-Authors: Young-min Kim, Sangchul Jung, Jong-ki Jeon, Muhammad Zain Siddiqui, Hyung Won Lee, Jungho Jae, Jaehun Jeong, Sumin Ryu, Jung Sul Jung, Young-kwon ParkAbstract:Abstract Hierarchical zeolites have superior Catalytic properties over purely microporous zeolites, leading to the enhanced diffusivity of molecules and strong acidity of the catalyst. In this study, hierarchical desilicated mesoporous ZSM-5 and Beta were prepared by the desilication of commercial microporous zeolites and applied to the Catalytic Pyrolysis of wood polymer composites. Hierarchical desilicated mesoporous ZSM-5 and Beta showed the typical X-ray diffraction patterns of microporous ZSM-5 and Beta with higher mesoporosity compared to the parent materials. The activity of the desilicated zeolites for the Catalytic Pyrolysis of wood polymer composites was evaluated using a thermogravimetric analysis and tandem micro reactor-gas chromatography/mass spectrometry. Among the catalysts tested, the lowest decomposition temperatures of wood polymer composites were observed using hierarchical desilicated mesoporous Beta followed by hierarchical desilicated mesoporous ZSM-5 and ZSM-5. This trend correlated well with the mesoporosity of the catalysts. The formation efficiency of hierarchical desilicated mesoporous ZSM-5 was highest followed by microporous ZSM-5, hierarchical desilicated mesoporous Beta, and Beta, indicating that in addition to mesoporosity, the shape selectivity induced by microporosity and strong acidity are important for the aromatization of Pyrolysis vapors. In addition, the aromatic formation efficiency of the catalysts differed according to the properties of wood polymer composites. Compared to wood polymer composite 2, wood polymer composite 1 produced a larger quantity of aromatics during Catalytic Pyrolysis over all the catalysts at 500 °C owing to its higher polyethylene content. Both wood polymer composites exhibited a similar aromatic formation efficiency during Catalytic Pyrolysis at 600 °C because the diffusion hindering effect of polypropylene molecules to the catalyst pores was lower at the higher temperature.
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Catalytic Pyrolysis of organosolv and klason lignin over al sba 15
Journal of Nanoscience and Nanotechnology, 2018Co-Authors: Bosung Kang, Sangchul Jung, Jong-ki Jeon, Young-kwon ParkAbstract:: The Catalytic Pyrolysis of two types of lignin, organosolv and klason lignin, which were extracted from miscanthus, over Al-SBA-15 was carried out using a thermogravimetric (TG) analyzer and a pyroyzer-gas chromatography/mass spectrometry (Py-GC/MS). Although Al-SBA-15 has weak acidity, the large molecular phenolic pyrolyzates of lignin were converted effectively into small molecular phenols and aromatic hydrocarbons due to the large pore size of Al-SBA-15. Compared to klason lignin, organosolv lignin produced larger amounts of valuable chemicals, such as mono-phenol, mono-aromatics, and furans, by Catalytic Pyrolysis over Al-SBA-15.
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In-Situ Catalytic Pyrolysis of Xylan and Dealkaline Lignin over SAPO-11
Topics in Catalysis, 2017Co-Authors: Jong-ki Jeon, Sangchul Jung, Sung Hoon Park, Young-kwon ParkAbstract:Silicoaluminophosphate molecular sieve, SAPO-11, was applied for the first time to the Catalytic Pyrolysis of xylan and dealkaline lignin. The isothermal fast Catalytic Pyrolysis of xylan and dealkaline lignin over different amounts of SAPO-11 and their product analysis were performed concurrently using a pyrolyzer GC/MS. Large amounts of oxygenated pyrolyzates produced from the non-Catalytic Pyrolysis of xylan at 500 °C were converted to furans, light hydrocarbons, and aromatic hydrocarbons using SAPO-11. When the catalyst to sample ratio was increased from 1:1 to 5:1 and 10:1, the selectivity toward aromatic hydrocarbons was increased dramatically. Phenolic compounds, such as guaiacols and vanillin, were the main products of the non-Catalytic Pyrolysis of dealkaline lignin. These phenolic compounds were upgraded efficiently into aromatics by the Catalytic Pyrolysis of dealkaline lignin over SAPO-11. By increasing the catalyst to sample ratio from 1:1 to 10:1, much larger amounts of aromatic hydrocarbons were obtained due to the increased catalyst acid sites. A phenolic pool mechanism was suggested as the major reaction pathway for the Catalytic Pyrolysis of dealkaline lignin over SAPO-11.
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Catalytic Pyrolysis of Cork Oak Over Supercritical Hydrothermal Synthesized Nanosized ZrO2
Journal of nanoscience and nanotechnology, 2017Co-Authors: Yejin Lee, Sangchul Jung, Jong-ki Jeon, Sung Hoon Park, Sang Chai Kim, Heejin Lee, Rae-su Park, Yeojin Hong, Young-kwon ParkAbstract:The change in acidity of Pyrolysis bio-oil was investigated using the Catalytic Pyrolysis of cork oak over zirconia synthesized by supercritical hydrothermal synthesis using a fixed bed reactor. Catalytic Pyrolysis over zirconia reduced the content of acetic acid considerably and showed high selectivity to ketones and high-value-added aromatic compounds.
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Catalytic Pyrolysis of lignin using a two-stage fixed bed reactor comprised of in-situ natural zeolite and ex-situ HZSM-5
Journal of Analytical and Applied Pyrolysis, 2016Co-Authors: Hyung Won Lee, Sangchul Jung, Jong-ki Jeon, Sang Chai Kim, Young-min Kim, Jungho Jae, Bong Hyun Sung, Young-kwon ParkAbstract:Abstract The two-stage Catalytic Pyrolysis of lignin over in-situ natural zeolite (NZ) and ex-situ HZSM-5 was examined using a tandem fixed bed reactor. The physicochemical properties of the catalysts, HZSM-5 and NZ, were characterized by N2 adsorption-desorption and temperature programed desorption of ammonia. The overall performance for the Catalytic Pyrolysis of lignin was evaluated by the comparing lignin conversion, aromatic formation, and amount of coke deposited from the two-stage Catalytic Pyrolysis with those from a single-stage Catalytic Pyrolysis with ex-situ HZSM-5. Compared to the single-stage Catalytic Pyrolysis, the two-stage Catalytic Pyrolysis produced a larger amount of aromatics with a smaller amount of coke due to the pre-Catalytic effect of NZ. These positive effects caused by the use of the two-stage catalyst were maximized by increasing the amounts of in-situ natural zeolite and the temperature of the ex-situ HZSM-5 catalyst bed to 600 °C.
Jinsen Gao - One of the best experts on this subject based on the ideXlab platform.
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Seven-lump kinetic model for Catalytic Pyrolysis of heavy oil
Catalysis Communications, 2007Co-Authors: Xianghai Meng, Jinsen GaoAbstract:Abstract A 7-lump kinetic model is proposed to describe the Catalytic Pyrolysis of heavy oil. The kinetic model contains 15 kinetic constants and one for catalyst deactivation. The experimental data were obtained in a confined fluidized bed reactor. The kinetic constants were estimated by a special program compiled based on the Marquardt’s algorithm. The apparent activation energies were calculated according to the Arrhenius equation. This model fits the experimental data well. The prediction shows that Catalytic Pyrolysis of Chinese Daqing atmospheric residue should be conducted at low space velocity to produce much ethene and at space velocity around 15 h −1 to produce much propene and butene.
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Production of Light Olefins by Catalytic Pyrolysis of Heavy Oil
Petroleum Science and Technology, 2006Co-Authors: Xianghai Meng, Jinsen GaoAbstract:Catalytic Pyrolysis is a promising technology for the production of light olefins. In this article, current advances in Catalytic Pyrolysis with respect to Pyrolysis catalysts, technologies and reaction mechanisms are summarized. An experimental laboratory method, based on a confined fluidized bed reactor, has been used to study Catalytic Pyrolysis of Chinese Daqing atmospheric residue over three different catalysts: LCM-5, CEP-1, and RSCC-29. Analysis of pyrolyzed gases shows that product yields are strongly dependent on catalyst type. The optimal operating conditions vary with catalyst type, but in each case, the yields of total light olefins show maxima with increasing temperature. Pyrolyzed liquids are primarily aromatic components, indicating that the degree of Catalytic Pyrolysis is very deep. Hydrogen balance analysis shows that the Catalytic Pyrolysis of heavy oil is capable of producing light olefins with high hydrogen contents.
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Reaction behaviors and mechanisms of Catalytic Pyrolysis of C4 hydrocarbons
Chemical Engineering Journal, 2006Co-Authors: Jinsen Gao, Xianghai MengAbstract:Catalytic Pyrolysis of C4 hydrocarbons over a modified ZSM-5 zeolite was investigated in a fixed bed reactor. The effects of reaction temperature and dilution ratio on product yields and distribution were studied, ethylene yield goes up monotonously with the enhancement of reaction temperature; meanwhile, propylene yield shows a maximum at about 580 °C. As dilution ratio increases, the yield of propylene increases until a dilution ratio of 2.0 is reached, and then changes slightly, and that of ethylene passes through a maximum at about 2.0. For Catalytic Pyrolysis of n-butylene, two reaction pathways have been proposed, the monomolecular reaction mechanism and the bimolecular reaction mechanism. With the analysis of these two reaction pathways and the experimental data, a conclusion is drawn that Catalytic Pyrolysis of n-butylene follows the bimolecular reaction mechanism. According to this mechanism, n-butylene Catalytic Pyrolysis involves two successive reaction steps: the dimerization of n-butylene and the cracking of the dimers.
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Catalytic Pyrolysis of heavy oils : 8-lump kinetic model
Applied Catalysis A: General, 2006Co-Authors: Xianghai Meng, Jinsen GaoAbstract:Abstract A new 8-lump kinetic model is proposed to describe the heavy oil Catalytic Pyrolysis process. The kinetic model contains 17 kinetic constants and one for catalyst deactivation. This paper also presents a new catalyst deactivation model, a function of feed properties and operating conditions, in which the deactivation constant doesn’t vary with reaction temperature. Kinetic constants and apparent activation energies were determined by the least square regression analysis of the experimental data, obtained in a confined fluidized bed reactor at temperatures of 600, 630, 660 and 700 °C. Most of the apparent activation energies are higher than 100 kJ/mol, between the apparent activation energies for Catalytic cracking and those for thermal cracking. The predicted results indicate that Catalytic Pyrolysis of heavy oils had better be conducted at high temperature and short residence time of oil gas, and heavy oils with the aromaticity higher than 30% had better not be considered as the feeds of Catalytic Pyrolysis.
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Studies on Catalytic Pyrolysis of heavy oils: Reaction behaviors and mechanistic pathways
Applied Catalysis A: General, 2005Co-Authors: Xianghai Meng, Jinsen GaoAbstract:Abstract Catalytic Pyrolysis of heavy oils on various catalysts was investigated in a confined fluidized bed reactor. As for Catalytic Pyrolysis of Chinese Daqing atmospheric residue (Daqing AR) on catalyst CEP-1, reaction temperature, residence time, weight ratios of catalyst-to-oil, steam-to-oil and feed properties have significant influence on product yields and product distribution. The optimal laboratory operating conditions are as follows: reaction temperature is within 650–680 °C, residence time within 2.0–4.0 s and catalyst-to-oil weight ratio within 13–18. The Catalytic Pyrolysis ability becomes better and the yields of light olefins become higher with the larger H / C mol ratio and the lower aromatic carbon content of feedstocks. After the cracking mechanisms of hydrocarbons are analyzed and the thermal Pyrolysis of Daqing AR is investigated, a mechanism parameter R M is proposed to study the mechanistic pathways of heavy oil Catalytic Pyrolysis. As for the processes of Daqing AR Catalytic Pyrolysis on catalysts LCM-5 and CEP-1, the relative acting percentage of the free radical mechanism and that of the carbonium ion mechanism are obtained.
Hyung Won Lee - One of the best experts on this subject based on the ideXlab platform.
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Upgrading of bio-oil by ex-situ Catalytic Pyrolysis and in-line esterification in fluidized bed reactor
Korean Journal of Chemical Engineering, 2020Co-Authors: Hyung Won Lee, Hanseob Jeong, Soo Min LeeAbstract:Ex-situ Catalytic Pyrolysis of Quercus mongolica over HZSM-5 and in-line esterification of Pyrolysis/Catalytic Pyrolysis vapors with liquid phase n-butyl alcohol were carried out in a fluidized bed reactor. The ex-situ Catalytic Pyrolysis over HZSM-5 beads was performed to produce bio-oil containing aromatic hydrocarbons. The temperature of the ex-situ Catalytic upgrading reaction was varied from 450 °C to 600 °C, and the maximum aromatic hydrocarbons yield was obtained at 450 °C. The selectivity for aromatic hydrocarbons as a function of Catalytic reaction temperature varied depending on aromatic ring number, as the selectivity for mono-aromatic hydrocarbons decreased and that for poly-aromatic hydrocarbons increased with temperature. In-line esterification of the Pyrolysis/Catalytic Pyrolysis vapors with liquid n-butyl alcohol was also carried out, and the GC/MS analysis results showed that the acids, aldehydes and ketones in the bio-oil were converted to esters and acetals.
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Catalytic Pyrolysis of wood polymer composites over hierarchical mesoporous zeolites
Energy Conversion and Management, 2019Co-Authors: Young-min Kim, Sangchul Jung, Jong-ki Jeon, Muhammad Zain Siddiqui, Hyung Won Lee, Jungho Jae, Jaehun Jeong, Sumin Ryu, Jung Sul Jung, Young-kwon ParkAbstract:Abstract Hierarchical zeolites have superior Catalytic properties over purely microporous zeolites, leading to the enhanced diffusivity of molecules and strong acidity of the catalyst. In this study, hierarchical desilicated mesoporous ZSM-5 and Beta were prepared by the desilication of commercial microporous zeolites and applied to the Catalytic Pyrolysis of wood polymer composites. Hierarchical desilicated mesoporous ZSM-5 and Beta showed the typical X-ray diffraction patterns of microporous ZSM-5 and Beta with higher mesoporosity compared to the parent materials. The activity of the desilicated zeolites for the Catalytic Pyrolysis of wood polymer composites was evaluated using a thermogravimetric analysis and tandem micro reactor-gas chromatography/mass spectrometry. Among the catalysts tested, the lowest decomposition temperatures of wood polymer composites were observed using hierarchical desilicated mesoporous Beta followed by hierarchical desilicated mesoporous ZSM-5 and ZSM-5. This trend correlated well with the mesoporosity of the catalysts. The formation efficiency of hierarchical desilicated mesoporous ZSM-5 was highest followed by microporous ZSM-5, hierarchical desilicated mesoporous Beta, and Beta, indicating that in addition to mesoporosity, the shape selectivity induced by microporosity and strong acidity are important for the aromatization of Pyrolysis vapors. In addition, the aromatic formation efficiency of the catalysts differed according to the properties of wood polymer composites. Compared to wood polymer composite 2, wood polymer composite 1 produced a larger quantity of aromatics during Catalytic Pyrolysis over all the catalysts at 500 °C owing to its higher polyethylene content. Both wood polymer composites exhibited a similar aromatic formation efficiency during Catalytic Pyrolysis at 600 °C because the diffusion hindering effect of polypropylene molecules to the catalyst pores was lower at the higher temperature.
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Catalytic Pyrolysis of lignin using a two-stage fixed bed reactor comprised of in-situ natural zeolite and ex-situ HZSM-5
Journal of Analytical and Applied Pyrolysis, 2016Co-Authors: Hyung Won Lee, Sangchul Jung, Jong-ki Jeon, Sang Chai Kim, Young-min Kim, Jungho Jae, Bong Hyun Sung, Young-kwon ParkAbstract:Abstract The two-stage Catalytic Pyrolysis of lignin over in-situ natural zeolite (NZ) and ex-situ HZSM-5 was examined using a tandem fixed bed reactor. The physicochemical properties of the catalysts, HZSM-5 and NZ, were characterized by N2 adsorption-desorption and temperature programed desorption of ammonia. The overall performance for the Catalytic Pyrolysis of lignin was evaluated by the comparing lignin conversion, aromatic formation, and amount of coke deposited from the two-stage Catalytic Pyrolysis with those from a single-stage Catalytic Pyrolysis with ex-situ HZSM-5. Compared to the single-stage Catalytic Pyrolysis, the two-stage Catalytic Pyrolysis produced a larger amount of aromatics with a smaller amount of coke due to the pre-Catalytic effect of NZ. These positive effects caused by the use of the two-stage catalyst were maximized by increasing the amounts of in-situ natural zeolite and the temperature of the ex-situ HZSM-5 catalyst bed to 600 °C.
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Catalytic Pyrolysis of Laminaria japonica over nanoporous catalysts using Py-GC/MS
Nanoscale Research Letters, 2011Co-Authors: Hyung Won Lee, Ho-jeong Chae, Jong-ki Jeon, Kwang-eun Jeong, Sung Hoon Park, Young-kwon ParkAbstract:The Catalytic Pyrolysis of Laminaria japonica was carried out over a hierarchical meso-MFI zeolite (Meso-MFI) and nanoporous Al-MCM-48 using Pyrolysis gas chromatography/mass spectrometry (Py-GC/MS). The effect of the catalyst type on the product distribution and chemical composition of the bio-oil was examined using Py-GC/MS. The Meso-MFI exhibited a higher activity in deoxygenation and aromatization during the Catalytic Pyrolysis of L. japonica. Meanwhile, the Catalytic activity of Al-MCM-48 was lower than that of Meso-MFI due to its weak acidity.