The Experts below are selected from a list of 5013 Experts worldwide ranked by ideXlab platform
Roger Ruan - One of the best experts on this subject based on the ideXlab platform.
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microwave assisted Pyrolysis of waste cooking oil for hydrocarbon bio oil over metal oxides and hzsm 5 catalysts
Energy Conversion and Management, 2020Co-Authors: Yunpu Wang, Lin Jiang, Qi Yang, Roger Ruan, Yuhuan Liu, Leilei Dai, Yujie Peng, Donghua XiaAbstract:Abstract Microwave-Assisted Pyrolysis of waste cooking oil is an environmentally friendly and economical method for obtaining benzene, toluene, ethylbenzene, and xylene (BTEX) which are important industrial chemicals. This study provides new routes to produce of BTEX and the utilization of waste cooking oil. The effect of catalytic temperatures (350 °C, 400 °C, 450 °C, 500 °C, and 550 °C), types of metal oxide (CoO, NiO, ZrO2, SrO, CeO2, and CaO), catalytic modes (ex-situ mixed catalysis, ex-situ separate catalysis, and in-situ separate catalysis), and ratio of HZSM-5 to metal oxide (HZSM-5 only, 4:1, 2:1, 1:1, 1:2, and CaO only) were studied. Results showed high catalytic temperature promoted the formation of monocyclic aromatic hydrocarbons at the cost of a decrease in bio-oil yield. But the concentration of BTEXS (benzene, toluene, ethylbenzene, xylene, and styrene) only increased from 256.58 mg/ml to 259.55 mg/ml with a temperature increase from 500 °C to 550 °C. Alkaline earth metal oxides (CaO, SrO) showed a significant deoxygenation capability during co-catalysis with HZSM-5. However, when CaO was applied under ex-situ mixed catalysis, the concentration of polycyclic aromatic hydrocarbons was up to 35.47%, which was much higher than 9.18% under HZSM-5 only. Also, the concentration of BTEXS decreased from 256.58 mg/ml (HZSM-5 only) to 167.54 mg/ml (HZSM-5 mixed with CaO). Further investigation of catalytic mode showed that ex-situ separate catalysis was more suitable for co-catalysis of alkaline earth metal oxides and HZSM-5. The concentration of BTEXS were both significantly higher than that of HZSM-5 only, which increased by 121.81 mg/ml for CaO and 108.52 mg/ml for SrO under ex-situ separate catalysis. Further study showed that the highest concentration of BTEXS was 702.20 mg/ml obtained when the ratio of HZSM-5 to CaO was 2:1. It was almost 2.8 times higher than HZSM-5 alone and 42.2 times higher than non-catalytic results.
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Microwave-Assisted Pyrolysis of vegetable oil soapstock: Comparative study of rapeseed, sunflower, corn, soybean, rice, and peanut oil soapstock
International Journal of Agricultural and Biological Engineering, 2019Co-Authors: Wang Yunpu, Roger Ruan, Zhang Shumei, Wu Qiuhao, Dengle Duan, Yuhuan Liu, Leilei Dai, Lin JiangAbstract:In this study, the effects of catalytic temperature and the type of soapstock on products from Microwave-Assisted Pyrolysis were investigated. HZSM-5 was used as the catalyst to study the Pyrolysis of six different soapstocks at 200°C, 300°C, and 400°C catalytic temperature. Results showed that the bio-oil yields initially increased and then decreased with the increase in catalytic temperature. When the catalytic temperature was 300°C, the bio-oil reached up to the maximum value (65.8 wt.%). Findings indicated that the composition of bio-oil was related to the degree of unsaturation of fatty acids sodium in the soapstocks. In the case of saturated fatty acid sodium, a series of alkanes was formed, whereas the Pyrolysis of monounsaturated fatty acid sodium resulted mainly in cycloalkanes, the cycloalkenes obtained from bio-oil was produced by polyunsaturated fatty acid sodium. Keywords: microwave Pyrolysis vegetable oil soapstock, HZSM-5, bio-oil DOI: 10.25165/j.ijabe.20191206.4599 Citation: Wang Y P, Zhang S M, Wu Q H, Duan D L, Liu Y H, Ruan R, et al. Microwave-Assisted Pyrolysis of vegetable oil soapstock: Comparative study of rapeseed, sunflower, corn, soybean, rice, and peanut oil soapstock. Int J Agric & Biol Eng, 2019; 12(6): 202–208.
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microwave assisted catalytic fast Pyrolysis coupled with microwave absorbent of soapstock for bio oil in a downdraft reactor
Energy Conversion and Management, 2019Co-Authors: Qiuhao Wu, Zhenting Yu, Junlin Wu, Yunpu Wang, Sha Yang, Lin Jiang, Qi Yang, Roger Ruan, Guiming FuAbstract:Abstract Microwave-Assisted Pyrolysis of biomass with HZSM-5 coupled with SiC as microwave-absorbent in a downdraft reactor is a promising method for obtaining hydrocarbon-rich bio-oil. The hydrocarbon content limits the economic and commercial viability of the bio-oil produced by Pyrolysis. In this study, the effects of catalytic temperature, feedstock-to-catalyst ratio, and WHSV on the yield and composition of bio-oil are studied. In addition, this study compared the influence of downdraft reaction and updraft reaction on the yield and composition of bio-oil. Furthermore, the stability of the catalyst is studied. Catalytic temperature and feedstock-to-catalyst ratio played pivotal roles in the yield and composition of bio-oil. WHSV has minimal influence on the bio-oil yield and composition within the scope of our research. Furthermore, the optimal catalytic temperature, feedstock-to-catalyst ratio and WHSV were 400 °C, 2:1, and 72 h−1, respectively. The results illustrated that the downdraft coupled with the microwave-absorbent was conducive to the formation of aromatic hydrocarbons. The HZSM-5 performed well in five replicate experimental cycles under optimal conditions in terms of bio-oil yield and aromatic hydrocarbon yield.
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microwave assisted catalytic Pyrolysis of chinese tallow kernel oil for aromatic production in a downdraft reactor
Journal of Analytical and Applied Pyrolysis, 2018Co-Authors: Zhenting Yu, Yunpu Wang, Lin Jiang, Roger Ruan, Dengle Duan, Yue Zhou, Yunfeng ZhaoAbstract:Abstract Microwave-Assisted Pyrolysis of Chinese tallow kernel oil with silicon carbide (SiC)-foamed ceramic catalyst in a downdraft reactor was carried out in this study. In this paper, we studied the influence of catalytic temperature, catalyst-to-feed ratio, and feeding rate on product distribution and chemical components of bio-oil. The aromatic proportion reached a maximum value of 89.707 wt% when catalytic conditions were set as follows: 300 °C catalytic temperature, 1:2 catalyst/feedstock ratio, and 1 ml/min feed rate. Fourier-transform infrared spectra were consistent with the results obtained from gas chromatography–mass spectrometry. Their outstanding thermal stability allowed SiC-foamed ceramics to perform well in five cycles of repeated experiments under optimal conditions. These results indicate that the SiC-foamed ceramics are promising catalysts for aromatic production in Microwave-Assisted Pyrolysis of Chinese tallow kernel oil in a downdraft reactor. This pathway can also improve the application prospects of microwave Pyrolysis technology.
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a review of catalytic microwave Pyrolysis of lignocellulosic biomass for value added fuel and chemicals
Bioresource Technology, 2017Co-Authors: Hervan Marion Morgan, Jianghui Liang, Yujing Liu, Hanping Mao, Aiping Shi, Hanwu Lei, Roger RuanAbstract:Lignocellulosic biomass is an abundant renewable resource and can be efficiently converted into bio-energy by a bio-refinery. From the various techniques available for biomass thermo-chemical conversion; microwave assisted Pyrolysis (MAP) seems to be the very promising. The principles of microwave technology were reviewed and the parameters for the efficient production of bio-oil using microwave technology were summarized. Microwave technology by itself cannot efficiently produce high quality bio-oil products, catalysts are used to improve the reaction conditions and selectivity for valued products during MAP. The catalysts used to optimize MAP are revised in the development of this article. The origins for bio-oils that are phenol rich or hydrocarbon rich are reviewed and their experimental results were summarized. The kinetics of MAP is discussed briefly in the development of the article. Future prospects and scientific development of MAP are also considered in the development of this article.
P A Schneider - One of the best experts on this subject based on the ideXlab platform.
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microwave Pyrolysis of sewage biosolids dielectric properties microwave susceptor role and its impact on biochar properties
Journal of Analytical and Applied Pyrolysis, 2017Co-Authors: Elsa Antunes, Mohan V Jacob, Graham Brodie, P A SchneiderAbstract:Abstract Microwave assisted Pyrolysis (MWAP) is an alternative heating approach to convert biosolids into value-added products, such as biochar, biogas and bio-oil. Studying the dielectric properties of biosolids is fundamental to understand the behaviour of this material under microwave irradiation and to design microwave assisted Pyrolysis systems. This study examined the dielectric properties of biosolids with changes in moisture content and applied microwave frequency. Results demonstrated that the dielectric constant decreases with decreasing moisture content and with increasing microwave frequency, but the dielectric loss factor of dry biosolids is almost zero. Simulations demonstrated that moisture content of biosolids impacts on the distribution and intensity of electromagnetic field. Because of the poor dielectric properties of dry biosolids, a microwave susceptor must be added to the biosolids to attract microwave energy so that the materials can reach temperatures required for Pyrolysis. Therefore, this study also investigated the impact of four microwave susceptors (activated carbon, charcoal, biochar and glycerol) on biosolids Pyrolysis and on biochar properties produced from biosolids via microwave assisted Pyrolysis at 600 °C. The choice of microwave susceptor influences the heating rate of biosolids and the specific surface area of the resultant biochar. Results show that activated carbon favours the heating process, increases surface area, and the biochar produced with activated carbon has the highest carbon stability and energy value.
Paul Chen - One of the best experts on this subject based on the ideXlab platform.
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in situ and ex situ catalytic upgrading of vapors from microwave assisted Pyrolysis of lignin
Bioresource Technology, 2018Co-Authors: Liangliang Fan, Yunpu Wang, Paul Chen, Yuhuan Liu, Nan Zhou, Shiyu Liu, Yaning Zhang, Muhammad Mubashar OmarAbstract:In-situ and ex-situ catalytic upgrading with HZSM-5 of vapors from Microwave-Assisted Pyrolysis of lignin were studied. The in-situ process produced higher bio-oil and less char than ex-situ process. The gas yield was similar for both processes. The ex-situ process had higher selectivity to aromatics and produced more syngas and less CO2 than the in-situ process. Additional experiments on ex-situ process found that the bio-oil yield and coke deposition decreased while the gas yield increased at higher catalyst-to-lignin ratios and catalytic upgrading temperatures. The increased catalyst-to-lignin ratio from 0 to 0.3 reduced the selectivity of methoxy phenols from 73.7% to 22.6% while increased that of aromatics from 1.1% to 41.4%. The highest selectivity of alkyl phenols (31.9%) was obtained at 0.2 of catalyst-to-lignin ratio. Higher catalytic temperatures favored greater conversion of methoxy phenols to alkyl phenols and aromatics. Appropriate catalyst-to-lignin ratio (0.3) together with higher catalytic temperatures favored syngas formation.
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ex situ catalytic upgrading of vapors from microwave assisted Pyrolysis of low density polyethylene with mgo
Energy Conversion and Management, 2017Co-Authors: Yunpu Wang, Paul Chen, Yuhuan Liu, Liangliang Fan, Nan Zhou, Shiyu Liu, Yaning Zhang, Peng PengAbstract:Abstract Ex-situ catalytic upgrading of vapors from Microwave-Assisted Pyrolysis of LDPE using MgO as the base catalyst was investigated and the effects of catalyst to reactant ratio, Pyrolysis temperature, and catalytic reaction temperature on the yields and chemical profiles of products were examined. 24.2–38.5 wt.% of ex-situ upgraded liquid yield were obtained under varied reaction conditions. Productive gas yield (higher than 56.6 wt.%) and low solid residue yield (less than 7.1 wt.%) were obtained as long as the Pyrolysis temperature was over 500 °C during the ex-situ upgrading process. The coke yield was negligible, ranging from 0.14 wt.% to 1.94 wt.% based on LDPE mass. The conversion of alkenes to aromatics was improved at higher catalyst to feedstock ratios, higher Pyrolysis temperatures, and higher catalytic reaction temperatures. The total percentage of gasoline fraction in the upgraded Pyrolysis oil ranged from 79.5% (37.3% mono-aromatics and 42.2% C5-C12 aliphatics) to 96.0% (39.7% mono-aromatics and 56.3% C5-C12 aliphatics) under various conditions, compared with 10.5% mono-aromatics and 30.2% C5-C12 aliphatics from non-catalytic Pyrolysis. The main composition of gas product was hydrogen, C1-C3 olefins and paraffins, varying with reaction condition. Both free radical and carbanion mechanisms for the conversion of LDPE with MgO were proposed.
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effects of feedstock characteristics on microwave assisted Pyrolysis a review
Bioresource Technology, 2017Co-Authors: Yaning Zhang, Paul Chen, Yanling Cheng, Liangliang Fan, Nan Zhou, Peng Peng, Shiyu Liu, Min Min, Erik Anderson, Chenghui LiuAbstract:Microwave-Assisted Pyrolysis is an important approach to obtain bio-oil from biomass. Similar to conventional electrical heating Pyrolysis, Microwave-Assisted Pyrolysis is significantly affected by feedstock characteristics. However, microwave heating has its unique features which strongly depend on the physical and chemical properties of biomass feedstock. In this review, the relationships among heating, bio-oil yield, and feedstock particle size, moisture content, inorganics, and organics in Microwave-Assisted Pyrolysis are discussed and compared with those in conventional electrical heating Pyrolysis. The quantitative analysis of data reported in the literature showed a strong contrast between the conventional processes and microwave based processes. Microwave-Assisted Pyrolysis is a relatively new process with limited research compared with conventional electrical heating Pyrolysis. The lack of understanding of some observed results warrant more and in-depth fundamental research.
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Bio-oil production from sequential two-step catalytic fast Microwave-Assisted biomass Pyrolysis
Fuel, 2017Co-Authors: Shiyu Liu, Yanling Cheng, Wang Yunpu, Yuhuan Liu, Liangliang Fan, Nan Zhou, Yaning Zhang, Gaoyou Tian, Xindi Zhu, Paul ChenAbstract:Abstract A sequential two-step fast Microwave-Assisted Pyrolysis (fMAP) for high quality bio-oil production was investigated. In the process, fMAP was followed by catalytic cracking and upgrading using a packed bed catalyst reactor with HZSM-5 as the catalyst. Effects of Pyrolysis temperature, catalyst loading, and catalyst bed temperature on the product distribution were investigated. Results showed that maximum bio-oil and aromatic hydrocarbons yields were obtained when Pyrolysis temperature reached 550 °C With the increase in the catalyst loading, the bio-oil yield decreased linearly while the aromatic hydrocarbons yield increased. The catalyst bed temperature also has a significant effect on the product chemical profiles. The aromatic hydrocarbons proportion of the bio-oil was found to increase with increasing catalyst bed temperature and reached its maximum of 26.20% at 425 °C. In addition, coke yield increased with increasing catalyst to biomass ratio and decreasing catalyst bed temperature.
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fast microwave assisted Pyrolysis of microalgae using microwave absorbent and hzsm 5 catalyst
Bioresource Technology, 2014Co-Authors: Fernanda Cabral Borges, Paul Chen, Jorge Otávio Trierweiler, Qinglong Xie, Min Min, Luis Antonio Rezende Muniz, Marcelo Farenzena, Roger RuanAbstract:Fast Microwave-Assisted Pyrolysis (fMAP) in the presence of a microwave absorbent (SiC) and catalyst (HZSM-5) was tested on a Chlorella sp. strain and on a Nannochloropsis strain. The liquid products were characterized, and the effects of temperature and catalyst:biomass ratio were analyzed. For Chlorella sp., a temperature of 550 °C, with no catalyst were the optimal conditions, resulting in a maximum bio-oil yield of 57 wt.%. For Nannochloropsis, a temperature of 500 °C, with 0.5 of catalyst ratio were shown to be the optimal condition, resulting in a maximum bio-oil yield of 59 wt.%. These results show that the use of microwave absorbents in fMAP increased bio-oil yields and quality, and it is a promising technology to improve the commercial application and economic outlook of microwave Pyrolysis technology. Additionally, the use of a different catalyst needs to be considered to improve the bio-oil characteristics.
Yunpu Wang - One of the best experts on this subject based on the ideXlab platform.
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microwave assisted Pyrolysis of waste cooking oil for hydrocarbon bio oil over metal oxides and hzsm 5 catalysts
Energy Conversion and Management, 2020Co-Authors: Yunpu Wang, Lin Jiang, Qi Yang, Roger Ruan, Yuhuan Liu, Leilei Dai, Yujie Peng, Donghua XiaAbstract:Abstract Microwave-Assisted Pyrolysis of waste cooking oil is an environmentally friendly and economical method for obtaining benzene, toluene, ethylbenzene, and xylene (BTEX) which are important industrial chemicals. This study provides new routes to produce of BTEX and the utilization of waste cooking oil. The effect of catalytic temperatures (350 °C, 400 °C, 450 °C, 500 °C, and 550 °C), types of metal oxide (CoO, NiO, ZrO2, SrO, CeO2, and CaO), catalytic modes (ex-situ mixed catalysis, ex-situ separate catalysis, and in-situ separate catalysis), and ratio of HZSM-5 to metal oxide (HZSM-5 only, 4:1, 2:1, 1:1, 1:2, and CaO only) were studied. Results showed high catalytic temperature promoted the formation of monocyclic aromatic hydrocarbons at the cost of a decrease in bio-oil yield. But the concentration of BTEXS (benzene, toluene, ethylbenzene, xylene, and styrene) only increased from 256.58 mg/ml to 259.55 mg/ml with a temperature increase from 500 °C to 550 °C. Alkaline earth metal oxides (CaO, SrO) showed a significant deoxygenation capability during co-catalysis with HZSM-5. However, when CaO was applied under ex-situ mixed catalysis, the concentration of polycyclic aromatic hydrocarbons was up to 35.47%, which was much higher than 9.18% under HZSM-5 only. Also, the concentration of BTEXS decreased from 256.58 mg/ml (HZSM-5 only) to 167.54 mg/ml (HZSM-5 mixed with CaO). Further investigation of catalytic mode showed that ex-situ separate catalysis was more suitable for co-catalysis of alkaline earth metal oxides and HZSM-5. The concentration of BTEXS were both significantly higher than that of HZSM-5 only, which increased by 121.81 mg/ml for CaO and 108.52 mg/ml for SrO under ex-situ separate catalysis. Further study showed that the highest concentration of BTEXS was 702.20 mg/ml obtained when the ratio of HZSM-5 to CaO was 2:1. It was almost 2.8 times higher than HZSM-5 alone and 42.2 times higher than non-catalytic results.
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microwave assisted catalytic fast Pyrolysis coupled with microwave absorbent of soapstock for bio oil in a downdraft reactor
Energy Conversion and Management, 2019Co-Authors: Qiuhao Wu, Zhenting Yu, Junlin Wu, Yunpu Wang, Sha Yang, Lin Jiang, Qi Yang, Roger Ruan, Guiming FuAbstract:Abstract Microwave-Assisted Pyrolysis of biomass with HZSM-5 coupled with SiC as microwave-absorbent in a downdraft reactor is a promising method for obtaining hydrocarbon-rich bio-oil. The hydrocarbon content limits the economic and commercial viability of the bio-oil produced by Pyrolysis. In this study, the effects of catalytic temperature, feedstock-to-catalyst ratio, and WHSV on the yield and composition of bio-oil are studied. In addition, this study compared the influence of downdraft reaction and updraft reaction on the yield and composition of bio-oil. Furthermore, the stability of the catalyst is studied. Catalytic temperature and feedstock-to-catalyst ratio played pivotal roles in the yield and composition of bio-oil. WHSV has minimal influence on the bio-oil yield and composition within the scope of our research. Furthermore, the optimal catalytic temperature, feedstock-to-catalyst ratio and WHSV were 400 °C, 2:1, and 72 h−1, respectively. The results illustrated that the downdraft coupled with the microwave-absorbent was conducive to the formation of aromatic hydrocarbons. The HZSM-5 performed well in five replicate experimental cycles under optimal conditions in terms of bio-oil yield and aromatic hydrocarbon yield.
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microwave assisted catalytic Pyrolysis of chinese tallow kernel oil for aromatic production in a downdraft reactor
Journal of Analytical and Applied Pyrolysis, 2018Co-Authors: Zhenting Yu, Yunpu Wang, Lin Jiang, Roger Ruan, Dengle Duan, Yue Zhou, Yunfeng ZhaoAbstract:Abstract Microwave-Assisted Pyrolysis of Chinese tallow kernel oil with silicon carbide (SiC)-foamed ceramic catalyst in a downdraft reactor was carried out in this study. In this paper, we studied the influence of catalytic temperature, catalyst-to-feed ratio, and feeding rate on product distribution and chemical components of bio-oil. The aromatic proportion reached a maximum value of 89.707 wt% when catalytic conditions were set as follows: 300 °C catalytic temperature, 1:2 catalyst/feedstock ratio, and 1 ml/min feed rate. Fourier-transform infrared spectra were consistent with the results obtained from gas chromatography–mass spectrometry. Their outstanding thermal stability allowed SiC-foamed ceramics to perform well in five cycles of repeated experiments under optimal conditions. These results indicate that the SiC-foamed ceramics are promising catalysts for aromatic production in Microwave-Assisted Pyrolysis of Chinese tallow kernel oil in a downdraft reactor. This pathway can also improve the application prospects of microwave Pyrolysis technology.
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in situ and ex situ catalytic upgrading of vapors from microwave assisted Pyrolysis of lignin
Bioresource Technology, 2018Co-Authors: Liangliang Fan, Yunpu Wang, Paul Chen, Yuhuan Liu, Nan Zhou, Shiyu Liu, Yaning Zhang, Muhammad Mubashar OmarAbstract:In-situ and ex-situ catalytic upgrading with HZSM-5 of vapors from Microwave-Assisted Pyrolysis of lignin were studied. The in-situ process produced higher bio-oil and less char than ex-situ process. The gas yield was similar for both processes. The ex-situ process had higher selectivity to aromatics and produced more syngas and less CO2 than the in-situ process. Additional experiments on ex-situ process found that the bio-oil yield and coke deposition decreased while the gas yield increased at higher catalyst-to-lignin ratios and catalytic upgrading temperatures. The increased catalyst-to-lignin ratio from 0 to 0.3 reduced the selectivity of methoxy phenols from 73.7% to 22.6% while increased that of aromatics from 1.1% to 41.4%. The highest selectivity of alkyl phenols (31.9%) was obtained at 0.2 of catalyst-to-lignin ratio. Higher catalytic temperatures favored greater conversion of methoxy phenols to alkyl phenols and aromatics. Appropriate catalyst-to-lignin ratio (0.3) together with higher catalytic temperatures favored syngas formation.
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ex situ catalytic upgrading of vapors from microwave assisted Pyrolysis of low density polyethylene with mgo
Energy Conversion and Management, 2017Co-Authors: Yunpu Wang, Paul Chen, Yuhuan Liu, Liangliang Fan, Nan Zhou, Shiyu Liu, Yaning Zhang, Peng PengAbstract:Abstract Ex-situ catalytic upgrading of vapors from Microwave-Assisted Pyrolysis of LDPE using MgO as the base catalyst was investigated and the effects of catalyst to reactant ratio, Pyrolysis temperature, and catalytic reaction temperature on the yields and chemical profiles of products were examined. 24.2–38.5 wt.% of ex-situ upgraded liquid yield were obtained under varied reaction conditions. Productive gas yield (higher than 56.6 wt.%) and low solid residue yield (less than 7.1 wt.%) were obtained as long as the Pyrolysis temperature was over 500 °C during the ex-situ upgrading process. The coke yield was negligible, ranging from 0.14 wt.% to 1.94 wt.% based on LDPE mass. The conversion of alkenes to aromatics was improved at higher catalyst to feedstock ratios, higher Pyrolysis temperatures, and higher catalytic reaction temperatures. The total percentage of gasoline fraction in the upgraded Pyrolysis oil ranged from 79.5% (37.3% mono-aromatics and 42.2% C5-C12 aliphatics) to 96.0% (39.7% mono-aromatics and 56.3% C5-C12 aliphatics) under various conditions, compared with 10.5% mono-aromatics and 30.2% C5-C12 aliphatics from non-catalytic Pyrolysis. The main composition of gas product was hydrogen, C1-C3 olefins and paraffins, varying with reaction condition. Both free radical and carbanion mechanisms for the conversion of LDPE with MgO were proposed.
Shiyu Liu - One of the best experts on this subject based on the ideXlab platform.
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in situ and ex situ catalytic upgrading of vapors from microwave assisted Pyrolysis of lignin
Bioresource Technology, 2018Co-Authors: Liangliang Fan, Yunpu Wang, Paul Chen, Yuhuan Liu, Nan Zhou, Shiyu Liu, Yaning Zhang, Muhammad Mubashar OmarAbstract:In-situ and ex-situ catalytic upgrading with HZSM-5 of vapors from Microwave-Assisted Pyrolysis of lignin were studied. The in-situ process produced higher bio-oil and less char than ex-situ process. The gas yield was similar for both processes. The ex-situ process had higher selectivity to aromatics and produced more syngas and less CO2 than the in-situ process. Additional experiments on ex-situ process found that the bio-oil yield and coke deposition decreased while the gas yield increased at higher catalyst-to-lignin ratios and catalytic upgrading temperatures. The increased catalyst-to-lignin ratio from 0 to 0.3 reduced the selectivity of methoxy phenols from 73.7% to 22.6% while increased that of aromatics from 1.1% to 41.4%. The highest selectivity of alkyl phenols (31.9%) was obtained at 0.2 of catalyst-to-lignin ratio. Higher catalytic temperatures favored greater conversion of methoxy phenols to alkyl phenols and aromatics. Appropriate catalyst-to-lignin ratio (0.3) together with higher catalytic temperatures favored syngas formation.
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ex situ catalytic upgrading of vapors from microwave assisted Pyrolysis of low density polyethylene with mgo
Energy Conversion and Management, 2017Co-Authors: Yunpu Wang, Paul Chen, Yuhuan Liu, Liangliang Fan, Nan Zhou, Shiyu Liu, Yaning Zhang, Peng PengAbstract:Abstract Ex-situ catalytic upgrading of vapors from Microwave-Assisted Pyrolysis of LDPE using MgO as the base catalyst was investigated and the effects of catalyst to reactant ratio, Pyrolysis temperature, and catalytic reaction temperature on the yields and chemical profiles of products were examined. 24.2–38.5 wt.% of ex-situ upgraded liquid yield were obtained under varied reaction conditions. Productive gas yield (higher than 56.6 wt.%) and low solid residue yield (less than 7.1 wt.%) were obtained as long as the Pyrolysis temperature was over 500 °C during the ex-situ upgrading process. The coke yield was negligible, ranging from 0.14 wt.% to 1.94 wt.% based on LDPE mass. The conversion of alkenes to aromatics was improved at higher catalyst to feedstock ratios, higher Pyrolysis temperatures, and higher catalytic reaction temperatures. The total percentage of gasoline fraction in the upgraded Pyrolysis oil ranged from 79.5% (37.3% mono-aromatics and 42.2% C5-C12 aliphatics) to 96.0% (39.7% mono-aromatics and 56.3% C5-C12 aliphatics) under various conditions, compared with 10.5% mono-aromatics and 30.2% C5-C12 aliphatics from non-catalytic Pyrolysis. The main composition of gas product was hydrogen, C1-C3 olefins and paraffins, varying with reaction condition. Both free radical and carbanion mechanisms for the conversion of LDPE with MgO were proposed.
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effects of feedstock characteristics on microwave assisted Pyrolysis a review
Bioresource Technology, 2017Co-Authors: Yaning Zhang, Paul Chen, Yanling Cheng, Liangliang Fan, Nan Zhou, Peng Peng, Shiyu Liu, Min Min, Erik Anderson, Chenghui LiuAbstract:Microwave-Assisted Pyrolysis is an important approach to obtain bio-oil from biomass. Similar to conventional electrical heating Pyrolysis, Microwave-Assisted Pyrolysis is significantly affected by feedstock characteristics. However, microwave heating has its unique features which strongly depend on the physical and chemical properties of biomass feedstock. In this review, the relationships among heating, bio-oil yield, and feedstock particle size, moisture content, inorganics, and organics in Microwave-Assisted Pyrolysis are discussed and compared with those in conventional electrical heating Pyrolysis. The quantitative analysis of data reported in the literature showed a strong contrast between the conventional processes and microwave based processes. Microwave-Assisted Pyrolysis is a relatively new process with limited research compared with conventional electrical heating Pyrolysis. The lack of understanding of some observed results warrant more and in-depth fundamental research.
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Bio-oil production from sequential two-step catalytic fast Microwave-Assisted biomass Pyrolysis
Fuel, 2017Co-Authors: Shiyu Liu, Yanling Cheng, Wang Yunpu, Yuhuan Liu, Liangliang Fan, Nan Zhou, Yaning Zhang, Gaoyou Tian, Xindi Zhu, Paul ChenAbstract:Abstract A sequential two-step fast Microwave-Assisted Pyrolysis (fMAP) for high quality bio-oil production was investigated. In the process, fMAP was followed by catalytic cracking and upgrading using a packed bed catalyst reactor with HZSM-5 as the catalyst. Effects of Pyrolysis temperature, catalyst loading, and catalyst bed temperature on the product distribution were investigated. Results showed that maximum bio-oil and aromatic hydrocarbons yields were obtained when Pyrolysis temperature reached 550 °C With the increase in the catalyst loading, the bio-oil yield decreased linearly while the aromatic hydrocarbons yield increased. The catalyst bed temperature also has a significant effect on the product chemical profiles. The aromatic hydrocarbons proportion of the bio-oil was found to increase with increasing catalyst bed temperature and reached its maximum of 26.20% at 425 °C. In addition, coke yield increased with increasing catalyst to biomass ratio and decreasing catalyst bed temperature.
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Two-step fast Microwave-Assisted Pyrolysis of biomass for bio-oil production using microwave absorbent and HZSM-5 catalyst
Journal of environmental sciences (China), 2016Co-Authors: Bo Zhang, Zhaoping Zhong, Qinglong Xie, Shiyu Liu, Roger RuanAbstract:A novel technology of two-step fast Microwave-Assisted Pyrolysis (fMAP) of corn stover for bio-oil production was investigated in the presence of microwave absorbent (SiC) and HZSM-5 catalyst. Effects of fMAP temperature and catalyst-to-biomass ratio on bio-oil yield and chemical components were examined. The results showed that this technology, employing microwave, microwave absorbent and HZSM-5 catalyst, was effective and promising for biomass fast Pyrolysis. The fMAP temperature of 500°C was considered the optimum condition for maximum yield and best quality of bio-oil. Besides, the bio-oil yield decreased linearly and the chemical components in bio-oil were improved sequentially with the increase of catalyst-to-biomass ratio from 1:100 to 1:20. The elemental compositions of bio-char were also determined. Additionally, compared to one-step fMAP process, two-step fMAP could promote the bio-oil quality with a smaller catalyst-to-biomass ratio.