Catalytic steam reforming of condensable vapors, i.e. bio-oil, derived from pyrolysis of biomass is an important process for hydrogen production, which is expected to form renewable and clean energy. The generation of...Catalytic steam reforming of condensable vapors, i.e. bio-oil, derived from pyrolysis of biomass is an important process for hydrogen production, which is expected to form renewable and clean energy. The generation of hydrogen from bio-oil was investigated from 250 to 750 ℃ by a MgO mixed C12A7-O^-(C12A7-MgO) catalyst in a fixed-bed micro-reactor. The hydrogen yield on C12A7-MgO was about 44% at 750 ℃. It is found that both the catalytic activity and catalysis life are improved by doping MgO. The XRD results show that the C12A7 structure of the positively charged lattice framework remains in the C12A7-MgO catalyst.展开更多
Fluidized bed biomass gasifiers can be employed to produce hydrogen-rich gas. A non-premixed combustion model is used for biomass air-steam gasification in the gasifier, and the simulations were carried out by using t...Fluidized bed biomass gasifiers can be employed to produce hydrogen-rich gas. A non-premixed combustion model is used for biomass air-steam gasification in the gasifier, and the simulations were carried out by using the FLUENT 6.0 software. The simulation results are compared with the experimental data. The effects of the steam to biomass ratio （S/B）, the equivalence ratio （ER）, and the size of biomass particles on the hydrogen yield were studied. Meanwhile, the distributions of hydrogen inside the gasifier at different conditions are also described.展开更多
A series of Mo-based catalysts prepared by sol-gel method using citric acid as complexant were successfully applied in the high efficient production of mixed alcohols from bio-syngas, derived from the biomass gasifica...A series of Mo-based catalysts prepared by sol-gel method using citric acid as complexant were successfully applied in the high efficient production of mixed alcohols from bio-syngas, derived from the biomass gasification. The Cu1Co1Fe1MO1Zn0.5-6%K catalyst exhibited a higher activity on the space-time yield of mixed alcohols, compared with the other Mobased catalysts. The carbon conversion significantly increases with rising temperature below 340 ℃, but the alcohol selectivity has an opposite trend. The maximum mixed alcohols yield derived from biomass gasification is 494.8 g/（kg catal·h） with the C2＋ （C2-C6 higher alcohols） alcohols of 80.4% under the tested conditions. The alcohol distributions are consistent with the Schulz-Flory plots, except methanol. In the alcohols products, the C2＋ alcohols （higher alcohols） dominate with a weight ratio of 70%-85%. The Mo-based cata- lysts have been characterized by X-ray diffraction and N2 adsorption/desorption. The clean bio-fules of mixed alcohols derived from bio-syngas with higher octane values could be used as transportation fuels or petrol additives.展开更多
We investigated high catalytic activity of Ni/HZSM-5 catalysts synthesized by the impregnation method, which was successfully applied for low-temperature steam reforming of bio-oil. The influences of the catalyst comp...We investigated high catalytic activity of Ni/HZSM-5 catalysts synthesized by the impregnation method, which was successfully applied for low-temperature steam reforming of bio-oil. The influences of the catalyst composition, reforming temperature and the molar ratio of steam to carbon fed on the stream reforming process of bio-oil over the Ni/HZSM-5 catalysts were investigated in the reforming reactor. The promoting effects of current passing through the catalyst on the bio-oil reforming were also studied using the electrochemical catalytic reforming approach. By comparing Ni/HZSM-5 with commonly used Ni/Al2O3 catalysts, the Ni2O/ZSM catalyst with Ni-loading content of about 20% on the HZSM-5 support showed the highest catalytic activity. Even at 450 ℃, the hydrogen yield of about 90% with a near complete conversion of bio-oil was obtained using the Ni2O/ZSM catalyst. It was found that the performance of the bio-oil reforming was remarkably enhanced by the HZSM-5 supporter and the current through the catalyst. The features of the Ni/HZSM-5 catalysts were also investigated via X-ray diffraction, inductively coupled plasma and atomic emission spectroscopy, hydrogen temperature-programmed reduction, and Brunauer-Emmett-Teller methods.展开更多
A dual-reactor, assembled with the on-line syngas conditioning and methanol synthesis, was successfully applied for high efficient conversion of rich CO2 bio-oil derived syngas to bio-methanol. In the forepart catalys...A dual-reactor, assembled with the on-line syngas conditioning and methanol synthesis, was successfully applied for high efficient conversion of rich CO2 bio-oil derived syngas to bio-methanol. In the forepart catalyst bed reactor, the catalytic conversion can effectively adjust the rich-CO2 crude bio-syngas into the CO-containing bio-syngas using the CuZnA1Zr catalyst. After the on-line syngas conditioning at 450℃, the CO2/CO ratio in the blo- syngas significantly decreased from 6.3 to 1.2. In the rearward catalyst bed reactor, the conversion of the conditioned bio-syngas to bio-methanol shows the maximum yield about 1.21 kg/（kgcatarh） MeOH with a methanol selectivity of 97.9% at 260 ~C and 5.05 MPa using conventional CuZnA1 catalyst, which is close to the level typically obtained in the conventional methanol synthesis process using natural gas. The influences of temperature, pressure and space velocity on the bio-methanol synthesis were also investigated in detail.展开更多
A storage and emission functional material of [Ca24Al28O64]^4＋·（Cl^-）3.80（O^2-）0.10 （C12A7-Cl^-）, was prepared by the solid-state reactions of CaCO3, γ-Al2O3, and CaCl2 in Cl2/Ar mixture atmosphere. The a...A storage and emission functional material of [Ca24Al28O64]^4＋·（Cl^-）3.80（O^2-）0.10 （C12A7-Cl^-）, was prepared by the solid-state reactions of CaCO3, γ-Al2O3, and CaCl2 in Cl2/Ar mixture atmosphere. The anionic species stored in the C12A7-Cl^- material were dominated by Cl^-, about （2.21±0.24） × 10^21 cm^-3, accompanied by a small amount of O^2-, O^-, and O2^-, measured via ion chromatography, electron paramagnetic resonance, and raman spectra measurements. These results also corroborate identification of time-of-flight mass spectroscopy--the anionic species emitted from the C12A7-Cl^- surface were dominated by the Cl^- （about 90%） together with a small amount of O^- and electrons. The structure and morphological alterations of the material were investigated via X-ray diffraction and field emission scanning electron microscope, respectively.展开更多
We reports an efficient approach for production of hydrogen from crude bio-oil and biomass char in the dual fixed-bed system by using the electrochemical catalytic reforming method. The maximal absolute hydrogen yield...We reports an efficient approach for production of hydrogen from crude bio-oil and biomass char in the dual fixed-bed system by using the electrochemical catalytic reforming method. The maximal absolute hydrogen yield reached 110.9 g H2/kg dry biomass. The product gas was a mixed gas containing 72%H2, 26%CO2, 1.9%CO, and a trace amount of CH4. It was observed that adding biomass char （a by-product of pyrolysis of biomass） could remarkably increase the absolute H2 yield （about 20%-50%）. The higher reforming temperature could enhance the steam reforming reaction of organic compounds in crude bio-oil and the reaction of CO and H20. In addition, the CuZn-Al2O3 catalyst in the water-gas shift bed could also increase the absolute H2 yield via shifting CO to CO2.展开更多
The reforming of anisole （as model compound of bio-oil） was performed over the NiCuZn-Al2O3 catalyst, using a recently-developed electrochemical catalytic reforming （ECR）. The influence of-the current on the aniso...The reforming of anisole （as model compound of bio-oil） was performed over the NiCuZn-Al2O3 catalyst, using a recently-developed electrochemical catalytic reforming （ECR）. The influence of-the current on the anisole reforming in the ECR process has been investigated. It was observed that anisole reforming was significantly enhanced by the current approached over the catalyst in the electrochemical catalytic process, which was due to the non-uniform temperature distribution in the catalytic bed and the role of the thermal electrons originating from the electrified wire. The maximum hydrogen yield of 88.7% with a carbon conversion of 98.3% was obtained through the ECR reforming of anisole at 700℃ and 4 A. X-ray diffraction was employed to characterize catalyst features and their alterations in the anisole reforming. The apparent activation energy for the anisole reforming is calculated as 99.54 kJ/mol, which is higher than ethanol, acetic acid, and light fraction of bio-oil. It should owe to different physical and chemical properties and reforming mechanism for different hydrocarbons.展开更多
High-efficient production of hydrogen from bio-oil was performed by electrochemical catalytic reforming method over the CoZnAl catalyst. The influence of current on the hydrogen yield, carbon conversion, and products ...High-efficient production of hydrogen from bio-oil was performed by electrochemical catalytic reforming method over the CoZnAl catalyst. The influence of current on the hydrogen yield, carbon conversion, and products distribution were investigated. Both the hydrogen yield and carbon conversion were remarkably enhanced by the current through the catalyst, reaching hydrogen yield of 70% and carbon conversion of 85% at a lower reforming temperature of 500 ℃. The influence of current on the properties of the CoZnAl catalyst was also characterized by X-ray diffraction, X-ray photoelectron spectroscopy, thermal gravimetric analysis, and Brunauer-Emmett-Teller measurements. The thermal electrons would play an important role in promoting the reforming reactions of the oxygenated-organic compounds in the bio-oil.展开更多
We provides a novel approach to generate low-temperature atomic oxygen anions （O-） emission using the cesium oxide-doped 12CaO.7Al2O3 （Cs2O-doped C12A7）. The maximal emission intensity of O- from the Cs2O-doped C1...We provides a novel approach to generate low-temperature atomic oxygen anions （O-） emission using the cesium oxide-doped 12CaO.7Al2O3 （Cs2O-doped C12A7）. The maximal emission intensity of O- from the Cs2O-doped C12A7 at 700℃ and 800 V/cm reached about 0.54μA/cm2, which was about two times as strong as that from the un-doped C12A7 （0.23 μA/cm2） under the same condition. The initiative temperature of the O- emission from the Cs2O-doped C12A7 was about 500 ℃, which was also much lower than the initiative temperature from the un-doped C12A7 （570 ℃） in the given field of 800 V/cm. High pure O- emission close to 100% could be obtained from the Cs2O-doped C12A7 under the lower temperature （〈550℃）. The emission features of the Cs2O-doped C12A7, including the emission distribution, temperature effect, and emission branching ratio have been investigated in detail and compared with the un-doped C12A7. The structure and storage characteristics of the resulting material were also investigated via X-ray diffraction and electron paramagnetic resonance. It was found that doping Cs2Oto C12A7 will lower the initiative emission temperature and enhance the emission intensity展开更多
基金supported by the National Natural Science Foundation of China(50772107)National Key Basic Research Program of China(973)(2007CB210206)National High-Tech Research and Development Program of China(863)(2009AA05Z435)~~
文摘Catalytic steam reforming of condensable vapors, i.e. bio-oil, derived from pyrolysis of biomass is an important process for hydrogen production, which is expected to form renewable and clean energy. The generation of hydrogen from bio-oil was investigated from 250 to 750 ℃ by a MgO mixed C12A7-O^-(C12A7-MgO) catalyst in a fixed-bed micro-reactor. The hydrogen yield on C12A7-MgO was about 44% at 750 ℃. It is found that both the catalytic activity and catalysis life are improved by doping MgO. The XRD results show that the C12A7 structure of the positively charged lattice framework remains in the C12A7-MgO catalyst.
基金supported by the National Natural Science Foundation of China (50772107)National Key Basic Research Program of China (973)(2007CB210206)National High-Tech Research and Development Program of China (863) (2009AA05Z435)~~
基金The project was supported by the National Natural Science Foundation of China (50772107)National Key Basic Research Program of China (973)(2007CB210206)National High-Tech Research and Development Program of China (863) (2009AA05Z435)~~
文摘Fluidized bed biomass gasifiers can be employed to produce hydrogen-rich gas. A non-premixed combustion model is used for biomass air-steam gasification in the gasifier, and the simulations were carried out by using the FLUENT 6.0 software. The simulation results are compared with the experimental data. The effects of the steam to biomass ratio （S/B）, the equivalence ratio （ER）, and the size of biomass particles on the hydrogen yield were studied. Meanwhile, the distributions of hydrogen inside the gasifier at different conditions are also described.
基金This work is supported Technical Research and by the National High Development Program （No.2009AA05Z435）, the National Basic Research Program of Ministry of Science and Technology of China （No.2007CB210206）, and the National Natural Science Foundation of China （No.50772107）.
文摘A series of Mo-based catalysts prepared by sol-gel method using citric acid as complexant were successfully applied in the high efficient production of mixed alcohols from bio-syngas, derived from the biomass gasification. The Cu1Co1Fe1MO1Zn0.5-6%K catalyst exhibited a higher activity on the space-time yield of mixed alcohols, compared with the other Mobased catalysts. The carbon conversion significantly increases with rising temperature below 340 ℃, but the alcohol selectivity has an opposite trend. The maximum mixed alcohols yield derived from biomass gasification is 494.8 g/（kg catal·h） with the C2＋ （C2-C6 higher alcohols） alcohols of 80.4% under the tested conditions. The alcohol distributions are consistent with the Schulz-Flory plots, except methanol. In the alcohols products, the C2＋ alcohols （higher alcohols） dominate with a weight ratio of 70%-85%. The Mo-based cata- lysts have been characterized by X-ray diffraction and N2 adsorption/desorption. The clean bio-fules of mixed alcohols derived from bio-syngas with higher octane values could be used as transportation fuels or petrol additives.
基金ACKNOWLEDGMENTS This work is supported by the National High Tech Research and Development Program （No.2009AA05Z435）, the National Basic Research Program of Ministry of Science and Technology of China （No.2007CB210206）, and the General Program of the National Natural Science Foundation of China （No.50772107）.
文摘We investigated high catalytic activity of Ni/HZSM-5 catalysts synthesized by the impregnation method, which was successfully applied for low-temperature steam reforming of bio-oil. The influences of the catalyst composition, reforming temperature and the molar ratio of steam to carbon fed on the stream reforming process of bio-oil over the Ni/HZSM-5 catalysts were investigated in the reforming reactor. The promoting effects of current passing through the catalyst on the bio-oil reforming were also studied using the electrochemical catalytic reforming approach. By comparing Ni/HZSM-5 with commonly used Ni/Al2O3 catalysts, the Ni2O/ZSM catalyst with Ni-loading content of about 20% on the HZSM-5 support showed the highest catalytic activity. Even at 450 ℃, the hydrogen yield of about 90% with a near complete conversion of bio-oil was obtained using the Ni2O/ZSM catalyst. It was found that the performance of the bio-oil reforming was remarkably enhanced by the HZSM-5 supporter and the current through the catalyst. The features of the Ni/HZSM-5 catalysts were also investigated via X-ray diffraction, inductively coupled plasma and atomic emission spectroscopy, hydrogen temperature-programmed reduction, and Brunauer-Emmett-Teller methods.
基金This work was supported by the National High Tech Research and Development Program （No.2009AA05Z435）, the National Basic Research Program of Ministry of Science and Technology of China （No.2007CB210206）, and the National Natural Science Foundation of China （No.50772107）.
文摘A dual-reactor, assembled with the on-line syngas conditioning and methanol synthesis, was successfully applied for high efficient conversion of rich CO2 bio-oil derived syngas to bio-methanol. In the forepart catalyst bed reactor, the catalytic conversion can effectively adjust the rich-CO2 crude bio-syngas into the CO-containing bio-syngas using the CuZnA1Zr catalyst. After the on-line syngas conditioning at 450℃, the CO2/CO ratio in the blo- syngas significantly decreased from 6.3 to 1.2. In the rearward catalyst bed reactor, the conversion of the conditioned bio-syngas to bio-methanol shows the maximum yield about 1.21 kg/（kgcatarh） MeOH with a methanol selectivity of 97.9% at 260 ~C and 5.05 MPa using conventional CuZnA1 catalyst, which is close to the level typically obtained in the conventional methanol synthesis process using natural gas. The influences of temperature, pressure and space velocity on the bio-methanol synthesis were also investigated in detail.
基金ACKNOWLEDGMENTS This work was supported by the National Natural Science Foundation of China （No.50772107）, the National High Tech Research and Development Program （No.2009AA05Z435）, and the National Basic Research Program （No.2007CB210206） of Ministry of Science and Technology of China.
文摘A storage and emission functional material of [Ca24Al28O64]^4＋·（Cl^-）3.80（O^2-）0.10 （C12A7-Cl^-）, was prepared by the solid-state reactions of CaCO3, γ-Al2O3, and CaCl2 in Cl2/Ar mixture atmosphere. The anionic species stored in the C12A7-Cl^- material were dominated by Cl^-, about （2.21±0.24） × 10^21 cm^-3, accompanied by a small amount of O^2-, O^-, and O2^-, measured via ion chromatography, electron paramagnetic resonance, and raman spectra measurements. These results also corroborate identification of time-of-flight mass spectroscopy--the anionic species emitted from the C12A7-Cl^- surface were dominated by the Cl^- （about 90%） together with a small amount of O^- and electrons. The structure and morphological alterations of the material were investigated via X-ray diffraction and field emission scanning electron microscope, respectively.
基金supported by the National Natural Science Foundation of China(50772107)National Key Basic Research Program of China(973)(2007CB210206)National High-Tech Research and Development Program of China(863)(2009AA05Z435)~~
基金This work was supported by the National Basic Research Program of Ministry of Science and Technology of China （No.2007CB210206）, the National High Tech Research and Development Program （No.2009AA05Z435）, and the National Natural Science Foundation of China （No.50772107）.
文摘We reports an efficient approach for production of hydrogen from crude bio-oil and biomass char in the dual fixed-bed system by using the electrochemical catalytic reforming method. The maximal absolute hydrogen yield reached 110.9 g H2/kg dry biomass. The product gas was a mixed gas containing 72%H2, 26%CO2, 1.9%CO, and a trace amount of CH4. It was observed that adding biomass char （a by-product of pyrolysis of biomass） could remarkably increase the absolute H2 yield （about 20%-50%）. The higher reforming temperature could enhance the steam reforming reaction of organic compounds in crude bio-oil and the reaction of CO and H20. In addition, the CuZn-Al2O3 catalyst in the water-gas shift bed could also increase the absolute H2 yield via shifting CO to CO2.
文摘The reforming of anisole （as model compound of bio-oil） was performed over the NiCuZn-Al2O3 catalyst, using a recently-developed electrochemical catalytic reforming （ECR）. The influence of-the current on the anisole reforming in the ECR process has been investigated. It was observed that anisole reforming was significantly enhanced by the current approached over the catalyst in the electrochemical catalytic process, which was due to the non-uniform temperature distribution in the catalytic bed and the role of the thermal electrons originating from the electrified wire. The maximum hydrogen yield of 88.7% with a carbon conversion of 98.3% was obtained through the ECR reforming of anisole at 700℃ and 4 A. X-ray diffraction was employed to characterize catalyst features and their alterations in the anisole reforming. The apparent activation energy for the anisole reforming is calculated as 99.54 kJ/mol, which is higher than ethanol, acetic acid, and light fraction of bio-oil. It should owe to different physical and chemical properties and reforming mechanism for different hydrocarbons.
基金ACKNOWLEDGMENTS This work was supported by the National Basic Research Program of Ministry of Science and Technology of China （No.2007CB210206）, the National High Technology Research and Development Program （No.2009AA05Z435）, the National Natural Science Foundation of China （No.50772107）, and the Demonstration and Applied Investigation of Biomass Clean Energy Base （No.2007-15）.
文摘High-efficient production of hydrogen from bio-oil was performed by electrochemical catalytic reforming method over the CoZnAl catalyst. The influence of current on the hydrogen yield, carbon conversion, and products distribution were investigated. Both the hydrogen yield and carbon conversion were remarkably enhanced by the current through the catalyst, reaching hydrogen yield of 70% and carbon conversion of 85% at a lower reforming temperature of 500 ℃. The influence of current on the properties of the CoZnAl catalyst was also characterized by X-ray diffraction, X-ray photoelectron spectroscopy, thermal gravimetric analysis, and Brunauer-Emmett-Teller measurements. The thermal electrons would play an important role in promoting the reforming reactions of the oxygenated-organic compounds in the bio-oil.
基金This work is supported by the National Natural Science Foundation of China （No.50772107）, the National High Tech Research and Development Program （No.2009AA05Z435）, and the National Basic Research Program of the Ministry of Science and Technology of China （No.2007CB210206）.
文摘We provides a novel approach to generate low-temperature atomic oxygen anions （O-） emission using the cesium oxide-doped 12CaO.7Al2O3 （Cs2O-doped C12A7）. The maximal emission intensity of O- from the Cs2O-doped C12A7 at 700℃ and 800 V/cm reached about 0.54μA/cm2, which was about two times as strong as that from the un-doped C12A7 （0.23 μA/cm2） under the same condition. The initiative temperature of the O- emission from the Cs2O-doped C12A7 was about 500 ℃, which was also much lower than the initiative temperature from the un-doped C12A7 （570 ℃） in the given field of 800 V/cm. High pure O- emission close to 100% could be obtained from the Cs2O-doped C12A7 under the lower temperature （〈550℃）. The emission features of the Cs2O-doped C12A7, including the emission distribution, temperature effect, and emission branching ratio have been investigated in detail and compared with the un-doped C12A7. The structure and storage characteristics of the resulting material were also investigated via X-ray diffraction and electron paramagnetic resonance. It was found that doping Cs2Oto C12A7 will lower the initiative emission temperature and enhance the emission intensity
