In the current study, the hybrid effect of a corona discharge and γ-alumina supported Ni catalysts in CO2 reforming of methane is investigated. The study includes both purely catalytic operation in the temperature ra...In the current study, the hybrid effect of a corona discharge and γ-alumina supported Ni catalysts in CO2 reforming of methane is investigated. The study includes both purely catalytic operation in the temperature range of 923-1023 K, and hybrid catalytic-plasma operation of DC corona discharge reactor at room temperature and ambient pressure. The effect of feed flow rate, discharge power and Ni/γ-Al2O3 catalysts are studied. When CH4/CO2 ratio in the feed is 1/2, the syngas of low Ha/CO ratio at about 0.56 is obtained, which is a potential feedstock for synthesis of liquid hydrocarbons. Although Ni catalyst is only active above 573 K, presence of Ni catalysts in the cold corona plasma reactor （T≤523 K） shows promising increase in the conversions of methane and carbon dioxide. When Ni catalysts are used in the plasma reaction, H2/CO ratios in the products are slightly modified, selectivity to CO increases whereas fewer by-products such as hydrocarbons and oxygenates are formed.展开更多
以镍基负载γ-Al2O3为催化剂,对环戊二烯(CPD)选择加氢制备环戊烯(CPE)的工艺过程进行了研究.以双环戊二烯(DCPD)为初始原料,经过精馏塔高温解聚后得到加氢原料环戊二烯,在装填了Ni/γ-Al2O3催化剂的常压固定床反应器中与氢气发生选择...以镍基负载γ-Al2O3为催化剂,对环戊二烯(CPD)选择加氢制备环戊烯(CPE)的工艺过程进行了研究.以双环戊二烯(DCPD)为初始原料,经过精馏塔高温解聚后得到加氢原料环戊二烯,在装填了Ni/γ-Al2O3催化剂的常压固定床反应器中与氢气发生选择加氢反应.实验结果表明:适宜的催化剂制备条件为:Ni含量20%,浸渍时间12 h;适宜的工艺操作条件为:预还原温度500℃,氢烃比1.0,液空速6.0 h 1.在此条件下,CPD的转化率达到87.7%,CPE的选择性为92.8%.展开更多
γ-Al2O3 supported Ni-Mn bimetallic catalysts for CO2 reforming of methane were prepared by impregnation method. The reforming reactions were conducted at 500-700℃ and atmospheric pressure using CO2/CH4/N2 with feed ...γ-Al2O3 supported Ni-Mn bimetallic catalysts for CO2 reforming of methane were prepared by impregnation method. The reforming reactions were conducted at 500-700℃ and atmospheric pressure using CO2/CH4/N2 with feed ratio of 17/17/2, at total flow rate of 36 mL/min. The catalytic performance was assessed through CH4 and CO2 conversions, synthesis gas ratio （H2/CO） and long term stability. Catalytic activity and stability tests revealed that addition of Mn improved catalytic performance and led to higher stability of bimetallic catalysts which presented better coke suppression than monometallic catalyst. In this work, the optimum loading of Mn which exhibited the most stable performance and least coke deposition was 0.5wt%. The fresh and spent catalysts were characterized by various techniques such as Brunauer-Emmett-Teller, the temperature programmed desorption CO2- TPD, thermogravimetric analysis, X-ray diffraction, scanning electron microscope, EDX, and infrared spectroscopy.展开更多
At atmospheric pressure and ambient temperature, the hydrogenation coupling of methane was studied by using pulse corona plasma and its synergism with catalyst. The results showed that (i) under pulse corona plasma, t...At atmospheric pressure and ambient temperature, the hydrogenation coupling of methane was studied by using pulse corona plasma and its synergism with catalyst. The results showed that (i) under pulse corona plasma, the coupling of methane could be fulfilled by the addition of hydrogen, and with the increase of the amount of hydrogen, the conversion of methane and the yield of C2 hydrocarbon increased, and the deposit of carbon decreased; (ii) the conversion of methane was affected by pulse voltage and repeated frequency; (iii) in the system, the addition of Ni/γ-Al2O3 could improve the distribution of C2 hydrocarbon; (iv) the activity of Ni/γ-Al2O3 prepared by cold plasma was better than that by chemical methods. The experiment opened up a new technical route of the coupling of methane.展开更多
Hydrogen production from steam reforming of bio-oil and acetic acid using Ni/γ-Al2O3 catalyst was studied in a laboratory-scale fixed bed reactor.This study selected different Ni loadings(16.8%and 30.5%)in Ni/γ-Al2O...Hydrogen production from steam reforming of bio-oil and acetic acid using Ni/γ-Al2O3 catalyst was studied in a laboratory-scale fixed bed reactor.This study selected different Ni loadings(16.8%and 30.5%)in Ni/γ-Al2O3 catalysts and reaction temperatures(500°C,600°C and 700°C)as variables to optimize the hydrogen yield and selectivity of gases formed.Experiments were carried out in an isothermal manner.The catalysts were prepared on wet impregnation of aγ-Al2O3 which supported with two different Ni loadings.The principal gases generated were H2,CO,CO2 and CH4.The results from steam reforming of acetic acid showed that the yield and selectivity of hydrogen using the catalyst with 30.5%Ni were significantly higher than that with 16.8%Ni.The results showed that the most favorable temperature for hydrogen production was 600°C,and the steam reforming of bio-oil using Ni/γ-Al2O3 catalyst with 30.5%Ni showed that the yields and selectivity of H2 and CO2 increased with the temperature increasing while CH4 and CO selectivity decreased.These results showed that the most favorable temperature for hydrogen production from bio-oil using 30.5%Ni/γ-Al2O3 was 600°C,at which hydrogen yield was at its maximum of 65%.展开更多
Supported nickel-based catalysts were prepared by the incipient wetness impregnation method for the selective hydrogenation of methyl isobutyl ketone to methyl isobutyl carbinol in a fixed-bed reactor. The effects of ...Supported nickel-based catalysts were prepared by the incipient wetness impregnation method for the selective hydrogenation of methyl isobutyl ketone to methyl isobutyl carbinol in a fixed-bed reactor. The effects of the nickel source,Ni loading, calcination time, and calcination temperature on the hydrogenation performance were studied. The experimental results showed that the Ni/γ-Al_2O_3 catalyst demonstrated the highest catalytic performance under the preparation conditions by using nickel nitrate as the nickel source with a NiO loading of 20%, followed by calcination at 440°C for 5h. In addition,this catalyst showed the largest specific surface area, best crystal structure, highest active component content, smallest particle size, and uniform distribution of NiO on the surface of the carrier. The nickel-based catalyst prepared using the optimized conditions exhibited a 96.1% conversion of methyl isobutyl ketone, with a methyl isobutyl carbinol selectivity of 99.6%. The described procedure is very effective for the preparation of methyl isobutyl carbinol using methyl isobutyl ketone as the feedstock.展开更多
基金supported by the National Iranian Oil Company (N.I.O.C.)
文摘In the current study, the hybrid effect of a corona discharge and γ-alumina supported Ni catalysts in CO2 reforming of methane is investigated. The study includes both purely catalytic operation in the temperature range of 923-1023 K, and hybrid catalytic-plasma operation of DC corona discharge reactor at room temperature and ambient pressure. The effect of feed flow rate, discharge power and Ni/γ-Al2O3 catalysts are studied. When CH4/CO2 ratio in the feed is 1/2, the syngas of low Ha/CO ratio at about 0.56 is obtained, which is a potential feedstock for synthesis of liquid hydrocarbons. Although Ni catalyst is only active above 573 K, presence of Ni catalysts in the cold corona plasma reactor （T≤523 K） shows promising increase in the conversions of methane and carbon dioxide. When Ni catalysts are used in the plasma reaction, H2/CO ratios in the products are slightly modified, selectivity to CO increases whereas fewer by-products such as hydrocarbons and oxygenates are formed.
文摘以镍基负载γ-Al2O3为催化剂,对环戊二烯(CPD)选择加氢制备环戊烯(CPE)的工艺过程进行了研究.以双环戊二烯(DCPD)为初始原料,经过精馏塔高温解聚后得到加氢原料环戊二烯,在装填了Ni/γ-Al2O3催化剂的常压固定床反应器中与氢气发生选择加氢反应.实验结果表明:适宜的催化剂制备条件为:Ni含量20%,浸渍时间12 h;适宜的工艺操作条件为:预还原温度500℃,氢烃比1.0,液空速6.0 h 1.在此条件下,CPD的转化率达到87.7%,CPE的选择性为92.8%.
文摘γ-Al2O3 supported Ni-Mn bimetallic catalysts for CO2 reforming of methane were prepared by impregnation method. The reforming reactions were conducted at 500-700℃ and atmospheric pressure using CO2/CH4/N2 with feed ratio of 17/17/2, at total flow rate of 36 mL/min. The catalytic performance was assessed through CH4 and CO2 conversions, synthesis gas ratio （H2/CO） and long term stability. Catalytic activity and stability tests revealed that addition of Mn improved catalytic performance and led to higher stability of bimetallic catalysts which presented better coke suppression than monometallic catalyst. In this work, the optimum loading of Mn which exhibited the most stable performance and least coke deposition was 0.5wt%. The fresh and spent catalysts were characterized by various techniques such as Brunauer-Emmett-Teller, the temperature programmed desorption CO2- TPD, thermogravimetric analysis, X-ray diffraction, scanning electron microscope, EDX, and infrared spectroscopy.
文摘At atmospheric pressure and ambient temperature, the hydrogenation coupling of methane was studied by using pulse corona plasma and its synergism with catalyst. The results showed that (i) under pulse corona plasma, the coupling of methane could be fulfilled by the addition of hydrogen, and with the increase of the amount of hydrogen, the conversion of methane and the yield of C2 hydrocarbon increased, and the deposit of carbon decreased; (ii) the conversion of methane was affected by pulse voltage and repeated frequency; (iii) in the system, the addition of Ni/γ-Al2O3 could improve the distribution of C2 hydrocarbon; (iv) the activity of Ni/γ-Al2O3 prepared by cold plasma was better than that by chemical methods. The experiment opened up a new technical route of the coupling of methane.
基金The authors gratefully thank the support for this research from the Major State Basic Research Development Program of China(2012AA101808)Project 51206100 and 51276103 supported by National Natural Science Foundation of China,Project ZR2012EEQ018 supported by Shandong Provincial Natural Science Foundation,China,A Project of Shandong Province Higher Educational Science and Technology Program(J12LF12)Project 4072-112007 supported by Shandong University of Science and Technology Young Teachers Program.
文摘Hydrogen production from steam reforming of bio-oil and acetic acid using Ni/γ-Al2O3 catalyst was studied in a laboratory-scale fixed bed reactor.This study selected different Ni loadings(16.8%and 30.5%)in Ni/γ-Al2O3 catalysts and reaction temperatures(500°C,600°C and 700°C)as variables to optimize the hydrogen yield and selectivity of gases formed.Experiments were carried out in an isothermal manner.The catalysts were prepared on wet impregnation of aγ-Al2O3 which supported with two different Ni loadings.The principal gases generated were H2,CO,CO2 and CH4.The results from steam reforming of acetic acid showed that the yield and selectivity of hydrogen using the catalyst with 30.5%Ni were significantly higher than that with 16.8%Ni.The results showed that the most favorable temperature for hydrogen production was 600°C,and the steam reforming of bio-oil using Ni/γ-Al2O3 catalyst with 30.5%Ni showed that the yields and selectivity of H2 and CO2 increased with the temperature increasing while CH4 and CO selectivity decreased.These results showed that the most favorable temperature for hydrogen production from bio-oil using 30.5%Ni/γ-Al2O3 was 600°C,at which hydrogen yield was at its maximum of 65%.
基金financially supported by the National Natural Science Foundation of China (91634101)the Project on Construction of Innovative Teams and Teacher Career Development for Universities and Colleges under Beijing Municipality (IDHT20180508)
文摘Supported nickel-based catalysts were prepared by the incipient wetness impregnation method for the selective hydrogenation of methyl isobutyl ketone to methyl isobutyl carbinol in a fixed-bed reactor. The effects of the nickel source,Ni loading, calcination time, and calcination temperature on the hydrogenation performance were studied. The experimental results showed that the Ni/γ-Al_2O_3 catalyst demonstrated the highest catalytic performance under the preparation conditions by using nickel nitrate as the nickel source with a NiO loading of 20%, followed by calcination at 440°C for 5h. In addition,this catalyst showed the largest specific surface area, best crystal structure, highest active component content, smallest particle size, and uniform distribution of NiO on the surface of the carrier. The nickel-based catalyst prepared using the optimized conditions exhibited a 96.1% conversion of methyl isobutyl ketone, with a methyl isobutyl carbinol selectivity of 99.6%. The described procedure is very effective for the preparation of methyl isobutyl carbinol using methyl isobutyl ketone as the feedstock.
