Coal gasification fly ash(CGFA)is an industrial solid waste from the coal circulating fluidized bed(CFB)gasification process,and it needs to be effectively disposed to achieve sustainable development of the environmen...Coal gasification fly ash(CGFA)is an industrial solid waste from the coal circulating fluidized bed(CFB)gasification process,and it needs to be effectively disposed to achieve sustainable development of the environment.To realize the application of CGFA as a precursor of porous carbon materials,the physicochemical properties of three kinds of CGFA from industrial CFB gasifiers are analyzed.Then,the activation potential of CGFA is acquired via steam activation experiments in a tube furnace reactor.Finally,the fluidization activation technology of CGFA is practiced in a bench-scale CFB test rig,and its advantages are highlighted.The results show that CGFA is characterized by a high carbon content in the range of 54.06%–74.09%,an ultrafine particle size(d50:16.3–26.1 μm),and a relatively developed pore structure(specific surface area SSA:139.29–551.97 m^(2)·g^(-1)).The proportion of micropores in CGFA increases gradually with the coal rank.Steam activation experiments show that the pore development of CGFA mainly includes three stages:initial pore development,dynamic equilibrium between micropores and mesopores and pore collapse.The SSA of lignite fly ash(LFA),subbituminous fly ash(SBFA)and anthracite fly ash(AFA)is maximally increased by 105%,13%and 72%after steam activation;the order of the largest carbon reaction rate and decomposition ratio of steam among the three kinds of CGFA is SBFA>LFA>AFA.As the ratio of oxygen to carbon during the fluidization activation of LFA is from 0.09 to 0.19,the carbon conversion ratio increases from 14.4%to 26.8%and the cold gas efficiency increases from 6.8%to 10.2%.The SSA of LFA increases by up to 53.9%during the fluidization activation process,which is mainly due to the mesoporous development.Relative to steam activation in a tube furnace reactor,fluidization activation takes an extremely short time(seconds)to achieve the same activation effect.It is expected to further improve the activation effect of LFA by regulating the carbon conversion ratio range of 27%–35%to create pores in the initial development stage.展开更多
This work evaluated the effects of inherent alkali and alkaline earth metals on nitrogen transformation during steam gasification of Shengli lignite at the temperature of 873-1173 K in a fluidized-bed/fixed-bed quartz...This work evaluated the effects of inherent alkali and alkaline earth metals on nitrogen transformation during steam gasification of Shengli lignite at the temperature of 873-1173 K in a fluidized-bed/fixed-bed quartz reactor. The results indicated that the alkali metal Na and alkaline earth metals Ca, Mg in coal have different effects on inherent nitrogen transformation to NH3, HCN and char-N during the lignite steam gasification. Specifically during the steam gasification of Shengli lignite, Na and Ca, Mg not only catalyze the inherent nitrogen conversions to NH3, but also promote the secondary reactions of the nascent char-N as well as the generation of NH3 from the generated HCN, meanwhile they also inhibited the inherent nitrogen conversion to HCN and char-N. The presence of Na, Ca and Mg hindered the formation of oxidized nitrogen (N-X) functional groups, but enhanced pyridinic nitrogen (N-6) and quaternary nitrogen's (N-Q) formation in char.展开更多
The effects of the constituents of mineral matter in brown coals from different deposits of Kansk-Achinsk, Lenaand from Yallourn Basins on the structural parameters and steam gasification reactivities of respective co...The effects of the constituents of mineral matter in brown coals from different deposits of Kansk-Achinsk, Lenaand from Yallourn Basins on the structural parameters and steam gasification reactivities of respective coal chars at moderate temperature and at low and high pressure were studied in this paper. The data on how the preliminary decationization with diluted hydrochloric, acetic and sulphuric acids affect char gasification reactivities are presented. The importance of surface area and crystallinity of chars and the presence of naturally occurring metals on gasification reactivity is considered. Quantitative correlations between the calcium contents and the extents of gasification are revealed. The gasification results obtained in a flow reactor with steam stream and in an autoclave reactor at high pressure of gaseous products are compared. The catalytic effect of dispersed calcium oxide-carbonate particles produced from the naturally occurring calcium containing carboxylates was shown to be a key factor for char gasification reactivity, the effect in the flow reactor being much larger as compared to that in the autoclave reactor. This was mainly related to different forms of catalytically active calcium species and to the composition of the gaseous reaction mixture.展开更多
Biomass,a source of renewable energy,represents an effective substitute to fossil fuels.Gasification is a process that organics are thermochemically converted into valuable gaseous products(e.g.biogas).In this work,th...Biomass,a source of renewable energy,represents an effective substitute to fossil fuels.Gasification is a process that organics are thermochemically converted into valuable gaseous products(e.g.biogas).In this work,the catalytic test demonstrated that the biogas produced from biomass gasification mainly consists of H2,CH4,CO,and CO2,which were then be used as the fuel for solid oxide fuel cell(SOFC).Planar SOFCs were fabricated and adopted.The steam reforming of biogas was carried out at the anode of a SOFC to obtain a hydrogen-rich fuel.The performance of the SOFCs operating on generated biogas was investigated by I-V polarization and electrochemical impedance spectra characterizations.An excellent cell performance was obtained,for example,the peak power density of the SOFC reached 1391 mW·cm-2 at 750℃when the generated biogas was used as the fuel.Furthermore,the SOFC fuelled by simulated biogas delivered a very stable operation.展开更多
In the present study the catalytic steam gasification of biomass to produce hydrogen-rich gas with calcined dolomite and Nano-NiO/γ-Al2O3 as catalyst in an externally heated fixed bed reactor was investigated. The in...In the present study the catalytic steam gasification of biomass to produce hydrogen-rich gas with calcined dolomite and Nano-NiO/γ-Al2O3 as catalyst in an externally heated fixed bed reactor was investigated. The influence of the catalyst and reactor temperature on yield and product composition was studied at the temperature range of 700oC - 900oC. Over the ranges of experimental conditions examined, calcined dolomite revealed better catalytic performance, at the presence of steam, tar was completely decomposed as temperature increases from 800oC to 900oC. Higher temperature resulted in more H2 and CO2 production, and dry gas yield. The highest H2 content of 51.02 mol%, and the highest H2 yield of 1.66 m3/kg biomass were observed at the highest temperature level of 900oC.展开更多
This paper describes a single fluidized bed by the two-step gasification of the working method, process and biomass and coal co-gasification by a certain proportion of the results of a typical run. The results show th...This paper describes a single fluidized bed by the two-step gasification of the working method, process and biomass and coal co-gasification by a certain proportion of the results of a typical run. The results show that the biomass gasifi-cation technology for raw materials has a wide adaptability, the tar content in the gas is less than 10mg/m3,component in it ,the H2+CO>70%, H2/C ≈1~2,especially suitable for biomass from hydrogen, synthetic alcohol fuel, is a promising approach.展开更多
Alumina-supported bimetallic cobalt-nickel catalyst has been prepared and employed in a fixed-bed reactor for the direct production of synthesis gas from glycerol steam reforming. Physicochemical properties of the 5Co...Alumina-supported bimetallic cobalt-nickel catalyst has been prepared and employed in a fixed-bed reactor for the direct production of synthesis gas from glycerol steam reforming. Physicochemical properties of the 5Co-10Ni/85Al2O3 catalyst were determined from N2-physisorption, H2-chemisorption, CO2 and NH3-temperature-programmed desorption measurements as well as X-ray diffraction analysis. Both weak and strong acid sites are present on the catalyst surface. The acidic:basic ratio is about 7. Carbon deposition was evident at 923 K;addition of H2 however has managed to reduce the carbon deposition. Significantly, this has resulted in the increment of CH4 formation rate, consistent with the increased carbon gasification and methanation. Carbon deposition was almost non-existent, particularly at 1023 K. In addition, the inclusion of hydrogen also has contributed to the decrease of CO2 and increase of CO formation rates. This was attributed to the reverse water-gas-shift reaction. Overall, both the CO2:CO and CO2:CH4 ratios decrease with the hydrogen partial pressure.展开更多
In the present study the catalytic steam gasification of biomass to produce hydrogen-rich gas with calcined dolomite as catalyst in an externally heated fixed bed reactor was investigated. The influence of the reactor...In the present study the catalytic steam gasification of biomass to produce hydrogen-rich gas with calcined dolomite as catalyst in an externally heated fixed bed reactor was investigated. The influence of the reactor temperature on yield and product composition was studied at the temperature range of 700 PoPC-900 PoPC. Over the ranges of experimental con-ditions examined, tar was completely decomposed as temperature increases from 800P oPC to 900 PoPC. Higher temperature resulted in more HR2R and COR2R production, and dry gas yield. The highest H2 content of 51.02 V%, and the highest HR2 Ryield of 1.66 mP3P/kg biomass were observed at the highest temperature level of 900P oPC.展开更多
The poor-reactivity anthracite urgently needs more ways for large-scale and high-quality utilization.Due to the advantage of good fuel adaptability,the circulating fluidized bed(CFB)gasification technology has the pot...The poor-reactivity anthracite urgently needs more ways for large-scale and high-quality utilization.Due to the advantage of good fuel adaptability,the circulating fluidized bed(CFB)gasification technology has the potential of high-quality utilization of anthracite.In this paper,one kind of anthracite from Shanxi province,China,was employed to be gasified in a pilot-scale CFB gasifier.It is found that at the operating temperature of 1049℃and oxygen concentration of 60.75%,the gas with a concentration of combustibles of 66%and a low heating value of 7.93 MJ/m^(3)(at about 25℃and 101.325 kPa)was produced in the CFB gasification process.However,the overall gasification efficiency was not desired because a large amount of gasification fly ash(GFA)escaped and its yield was up to 22%.In this case,the cold gas efficiency was below 48%and the carbon conversion ratio was only 62%.Further analysis reveals that the GFA was featured with a developed pore structure and the specific surface area(S_(BET))reached 277 m^(2)/g.This indicates such GFA has a potential to use as activated carbon(AC)or AC precursor.Basis on this,steam activation experiments of the GFA produced were conducted to investigate the activation characteristics of GFA and thereby to determine its activation potential.Experimental results indicate that increasing temperature sharply accelerated the activation process,while did not impair the maximum activation effect.After activation,the S_(BET)of GFA maximumly increased by 63%,reaching452 m^(2)/g.With the progress of activation,the pore structure of GFA presents a three-stage evolution process:development,dynamic balance,and collapse.Such a process can be divided and quantified according to the carbon loss.In order to achieve an optimal activation of GFA,the carbon loss shall be controlled at~15%.This work provides a new scheme for high-quality utilization of anthracite.展开更多
The steam gasification characteristics of poplar sawdust were investigated in a piston fed fixed-bed gasifier,reflecting the batch feeding process of fixed-bed gasifiers in industrial applications.The effects of opera...The steam gasification characteristics of poplar sawdust were investigated in a piston fed fixed-bed gasifier,reflecting the batch feeding process of fixed-bed gasifiers in industrial applications.The effects of operating conditions,including steam supply,the flow rate of inert gas,gasification temperature,and feeding rate,on gasification reactivity and performance were investigated online.The major gas product during pyrolysis was CO,followed by H2,CH4,and CO_(2),and the gasification was greatly facilitated by the injection of steam to generate H2.The gasification reactivity and performance were improved with increased steam supply and temperature.The maximum production rate of H_(2)by char gasification was tripled and doubled,respectively,with an increase in steam supply from 50 to 400 mL/min and a temperature rise from 800 to 900◦C,and the time required for complete gasification was also halved.Compared to pyrolysis,the volume fraction of H2 increased from 23%to 37%,and correspondingly,the H_(2)/CO ratio increased from 0.42 to 0.95.展开更多
Gasification technology can effectively realize energy recovery from municipal solid waste(MSW)to reduce its negative impact on the environment.However,ammonia,as a pollutant derived from MSW gasification,needs to be ...Gasification technology can effectively realize energy recovery from municipal solid waste(MSW)to reduce its negative impact on the environment.However,ammonia,as a pollutant derived from MSW gasification,needs to be treated because its emission is considered harmful to mankind.This work aims to decompose the NH3 pollutant from MSW gasification by an in-situ catalytic method.The MSW sample is composed of rice,paper,polystyrene granules,rubber gloves,textile and wood chips.Ni–M(M=Co,Fe,Zn)bimetallic catalysts supported on sewage sludge-derived biochar(SSC)were prepared by co-impregnation method and further characterized by X-ray diffraction,N2 isothermal adsorption,scanning electron microscopy,transmission electron microscopy and NH3 temperature programmed desorption.Prior to the experiments,the catalysts were first homogeneously mixed with the MSW sample,and then in-situ catalytic tests were conducted in a horizontal fixed-bed reactor.The effect of the second metal(Co,Fe,Zn)on the catalytic performance was compared to screen the best Ni-M dual.It was found that the Ni–Co/SSC catalyst had the best activity toward NH3 decomposition,whose decomposition rate reached 40.21%at 650℃.The best catalytic performance of Ni–Co/SSC can be explained by its smaller Ni particle size that facilitates the dispersion of active sites as well as the addition of Co reducing the energy barrier for the associative decomposition of NH species during the NH3 decomposition process.Besides,the activity of Ni–Co/SSC increased from 450℃to 700℃as the NH3 decomposition reaction was endothermic.展开更多
基金financially supported by the Special Research Assistant Fund Project of Chinese Academy of Sciences.
文摘Coal gasification fly ash(CGFA)is an industrial solid waste from the coal circulating fluidized bed(CFB)gasification process,and it needs to be effectively disposed to achieve sustainable development of the environment.To realize the application of CGFA as a precursor of porous carbon materials,the physicochemical properties of three kinds of CGFA from industrial CFB gasifiers are analyzed.Then,the activation potential of CGFA is acquired via steam activation experiments in a tube furnace reactor.Finally,the fluidization activation technology of CGFA is practiced in a bench-scale CFB test rig,and its advantages are highlighted.The results show that CGFA is characterized by a high carbon content in the range of 54.06%–74.09%,an ultrafine particle size(d50:16.3–26.1 μm),and a relatively developed pore structure(specific surface area SSA:139.29–551.97 m^(2)·g^(-1)).The proportion of micropores in CGFA increases gradually with the coal rank.Steam activation experiments show that the pore development of CGFA mainly includes three stages:initial pore development,dynamic equilibrium between micropores and mesopores and pore collapse.The SSA of lignite fly ash(LFA),subbituminous fly ash(SBFA)and anthracite fly ash(AFA)is maximally increased by 105%,13%and 72%after steam activation;the order of the largest carbon reaction rate and decomposition ratio of steam among the three kinds of CGFA is SBFA>LFA>AFA.As the ratio of oxygen to carbon during the fluidization activation of LFA is from 0.09 to 0.19,the carbon conversion ratio increases from 14.4%to 26.8%and the cold gas efficiency increases from 6.8%to 10.2%.The SSA of LFA increases by up to 53.9%during the fluidization activation process,which is mainly due to the mesoporous development.Relative to steam activation in a tube furnace reactor,fluidization activation takes an extremely short time(seconds)to achieve the same activation effect.It is expected to further improve the activation effect of LFA by regulating the carbon conversion ratio range of 27%–35%to create pores in the initial development stage.
基金The authors gratefully acknowledge the financial support provided by the 12th Five-Year Plan of National Science and Technology Support (Grant 2012BAA04B02)the National Natural Science Foundation of China (No.21406261).
文摘This work evaluated the effects of inherent alkali and alkaline earth metals on nitrogen transformation during steam gasification of Shengli lignite at the temperature of 873-1173 K in a fluidized-bed/fixed-bed quartz reactor. The results indicated that the alkali metal Na and alkaline earth metals Ca, Mg in coal have different effects on inherent nitrogen transformation to NH3, HCN and char-N during the lignite steam gasification. Specifically during the steam gasification of Shengli lignite, Na and Ca, Mg not only catalyze the inherent nitrogen conversions to NH3, but also promote the secondary reactions of the nascent char-N as well as the generation of NH3 from the generated HCN, meanwhile they also inhibited the inherent nitrogen conversion to HCN and char-N. The presence of Na, Ca and Mg hindered the formation of oxidized nitrogen (N-X) functional groups, but enhanced pyridinic nitrogen (N-6) and quaternary nitrogen's (N-Q) formation in char.
文摘The effects of the constituents of mineral matter in brown coals from different deposits of Kansk-Achinsk, Lenaand from Yallourn Basins on the structural parameters and steam gasification reactivities of respective coal chars at moderate temperature and at low and high pressure were studied in this paper. The data on how the preliminary decationization with diluted hydrochloric, acetic and sulphuric acids affect char gasification reactivities are presented. The importance of surface area and crystallinity of chars and the presence of naturally occurring metals on gasification reactivity is considered. Quantitative correlations between the calcium contents and the extents of gasification are revealed. The gasification results obtained in a flow reactor with steam stream and in an autoclave reactor at high pressure of gaseous products are compared. The catalytic effect of dispersed calcium oxide-carbonate particles produced from the naturally occurring calcium containing carboxylates was shown to be a key factor for char gasification reactivity, the effect in the flow reactor being much larger as compared to that in the autoclave reactor. This was mainly related to different forms of catalytically active calcium species and to the composition of the gaseous reaction mixture.
基金financially supported by the National Natural Science Foundation of China(Grants Nos.51302135 and 51678291)the Natural Science Foundation of Jiangsu Province,China(Grant No.BK20190965)+1 种基金the Research Project of Nanjing Institute of Technology(Grant No.YKJ201435)the Australian Research Council(ARC)Discovery Early Career Researcher Award DE180100773。
文摘Biomass,a source of renewable energy,represents an effective substitute to fossil fuels.Gasification is a process that organics are thermochemically converted into valuable gaseous products(e.g.biogas).In this work,the catalytic test demonstrated that the biogas produced from biomass gasification mainly consists of H2,CH4,CO,and CO2,which were then be used as the fuel for solid oxide fuel cell(SOFC).Planar SOFCs were fabricated and adopted.The steam reforming of biogas was carried out at the anode of a SOFC to obtain a hydrogen-rich fuel.The performance of the SOFCs operating on generated biogas was investigated by I-V polarization and electrochemical impedance spectra characterizations.An excellent cell performance was obtained,for example,the peak power density of the SOFC reached 1391 mW·cm-2 at 750℃when the generated biogas was used as the fuel.Furthermore,the SOFC fuelled by simulated biogas delivered a very stable operation.
文摘In the present study the catalytic steam gasification of biomass to produce hydrogen-rich gas with calcined dolomite and Nano-NiO/γ-Al2O3 as catalyst in an externally heated fixed bed reactor was investigated. The influence of the catalyst and reactor temperature on yield and product composition was studied at the temperature range of 700oC - 900oC. Over the ranges of experimental conditions examined, calcined dolomite revealed better catalytic performance, at the presence of steam, tar was completely decomposed as temperature increases from 800oC to 900oC. Higher temperature resulted in more H2 and CO2 production, and dry gas yield. The highest H2 content of 51.02 mol%, and the highest H2 yield of 1.66 m3/kg biomass were observed at the highest temperature level of 900oC.
文摘This paper describes a single fluidized bed by the two-step gasification of the working method, process and biomass and coal co-gasification by a certain proportion of the results of a typical run. The results show that the biomass gasifi-cation technology for raw materials has a wide adaptability, the tar content in the gas is less than 10mg/m3,component in it ,the H2+CO>70%, H2/C ≈1~2,especially suitable for biomass from hydrogen, synthetic alcohol fuel, is a promising approach.
文摘Alumina-supported bimetallic cobalt-nickel catalyst has been prepared and employed in a fixed-bed reactor for the direct production of synthesis gas from glycerol steam reforming. Physicochemical properties of the 5Co-10Ni/85Al2O3 catalyst were determined from N2-physisorption, H2-chemisorption, CO2 and NH3-temperature-programmed desorption measurements as well as X-ray diffraction analysis. Both weak and strong acid sites are present on the catalyst surface. The acidic:basic ratio is about 7. Carbon deposition was evident at 923 K;addition of H2 however has managed to reduce the carbon deposition. Significantly, this has resulted in the increment of CH4 formation rate, consistent with the increased carbon gasification and methanation. Carbon deposition was almost non-existent, particularly at 1023 K. In addition, the inclusion of hydrogen also has contributed to the decrease of CO2 and increase of CO formation rates. This was attributed to the reverse water-gas-shift reaction. Overall, both the CO2:CO and CO2:CH4 ratios decrease with the hydrogen partial pressure.
文摘In the present study the catalytic steam gasification of biomass to produce hydrogen-rich gas with calcined dolomite as catalyst in an externally heated fixed bed reactor was investigated. The influence of the reactor temperature on yield and product composition was studied at the temperature range of 700 PoPC-900 PoPC. Over the ranges of experimental con-ditions examined, tar was completely decomposed as temperature increases from 800P oPC to 900 PoPC. Higher temperature resulted in more HR2R and COR2R production, and dry gas yield. The highest H2 content of 51.02 V%, and the highest HR2 Ryield of 1.66 mP3P/kg biomass were observed at the highest temperature level of 900P oPC.
基金financially supported by the Special Research Assistant Project,Chinese Academy of Sciences。
文摘The poor-reactivity anthracite urgently needs more ways for large-scale and high-quality utilization.Due to the advantage of good fuel adaptability,the circulating fluidized bed(CFB)gasification technology has the potential of high-quality utilization of anthracite.In this paper,one kind of anthracite from Shanxi province,China,was employed to be gasified in a pilot-scale CFB gasifier.It is found that at the operating temperature of 1049℃and oxygen concentration of 60.75%,the gas with a concentration of combustibles of 66%and a low heating value of 7.93 MJ/m^(3)(at about 25℃and 101.325 kPa)was produced in the CFB gasification process.However,the overall gasification efficiency was not desired because a large amount of gasification fly ash(GFA)escaped and its yield was up to 22%.In this case,the cold gas efficiency was below 48%and the carbon conversion ratio was only 62%.Further analysis reveals that the GFA was featured with a developed pore structure and the specific surface area(S_(BET))reached 277 m^(2)/g.This indicates such GFA has a potential to use as activated carbon(AC)or AC precursor.Basis on this,steam activation experiments of the GFA produced were conducted to investigate the activation characteristics of GFA and thereby to determine its activation potential.Experimental results indicate that increasing temperature sharply accelerated the activation process,while did not impair the maximum activation effect.After activation,the S_(BET)of GFA maximumly increased by 63%,reaching452 m^(2)/g.With the progress of activation,the pore structure of GFA presents a three-stage evolution process:development,dynamic balance,and collapse.Such a process can be divided and quantified according to the carbon loss.In order to achieve an optimal activation of GFA,the carbon loss shall be controlled at~15%.This work provides a new scheme for high-quality utilization of anthracite.
基金supported by the National Key Research and Development Program of China(No.2019YFC1906800).
文摘The steam gasification characteristics of poplar sawdust were investigated in a piston fed fixed-bed gasifier,reflecting the batch feeding process of fixed-bed gasifiers in industrial applications.The effects of operating conditions,including steam supply,the flow rate of inert gas,gasification temperature,and feeding rate,on gasification reactivity and performance were investigated online.The major gas product during pyrolysis was CO,followed by H2,CH4,and CO_(2),and the gasification was greatly facilitated by the injection of steam to generate H2.The gasification reactivity and performance were improved with increased steam supply and temperature.The maximum production rate of H_(2)by char gasification was tripled and doubled,respectively,with an increase in steam supply from 50 to 400 mL/min and a temperature rise from 800 to 900◦C,and the time required for complete gasification was also halved.Compared to pyrolysis,the volume fraction of H2 increased from 23%to 37%,and correspondingly,the H_(2)/CO ratio increased from 0.42 to 0.95.
基金supported by the National Key R&D Program of China(No.2019YFC1906803)Key R&D Program of Jiangsu Province(No.BE2021701).
文摘Gasification technology can effectively realize energy recovery from municipal solid waste(MSW)to reduce its negative impact on the environment.However,ammonia,as a pollutant derived from MSW gasification,needs to be treated because its emission is considered harmful to mankind.This work aims to decompose the NH3 pollutant from MSW gasification by an in-situ catalytic method.The MSW sample is composed of rice,paper,polystyrene granules,rubber gloves,textile and wood chips.Ni–M(M=Co,Fe,Zn)bimetallic catalysts supported on sewage sludge-derived biochar(SSC)were prepared by co-impregnation method and further characterized by X-ray diffraction,N2 isothermal adsorption,scanning electron microscopy,transmission electron microscopy and NH3 temperature programmed desorption.Prior to the experiments,the catalysts were first homogeneously mixed with the MSW sample,and then in-situ catalytic tests were conducted in a horizontal fixed-bed reactor.The effect of the second metal(Co,Fe,Zn)on the catalytic performance was compared to screen the best Ni-M dual.It was found that the Ni–Co/SSC catalyst had the best activity toward NH3 decomposition,whose decomposition rate reached 40.21%at 650℃.The best catalytic performance of Ni–Co/SSC can be explained by its smaller Ni particle size that facilitates the dispersion of active sites as well as the addition of Co reducing the energy barrier for the associative decomposition of NH species during the NH3 decomposition process.Besides,the activity of Ni–Co/SSC increased from 450℃to 700℃as the NH3 decomposition reaction was endothermic.