Herein,the effect of the Ru:Ni bimetallic composition in dual-function materials(DFMs)for the integrated CO_(2)capture and methanation process(ICCU-Methanation)is systematically evaluated and combined with a thorough ...Herein,the effect of the Ru:Ni bimetallic composition in dual-function materials(DFMs)for the integrated CO_(2)capture and methanation process(ICCU-Methanation)is systematically evaluated and combined with a thorough material characterization,as well as a mechanistic(in-situ diffuse reflectance infrared fourier-transform spectroscopy(in-situ DRIFTS))and computational(computational fluid dynamics(CFD)modelling)investigation,in order to improve the performance of Ni-based DFMs.The bimetallic DFMs are comprised of a main Ni active metallic phase(20 wt%)and are modified with low Ru loadings in the 0.1-1 wt%range(to keep the material cost low),supported on Na_(2)O/Al_(2)O_(3).It is shown that the addition of even a very low Ru loading(0.1-0.2 wt%)can drastically improve the material reducibility,exposing a significantly higher amount of surface-active metallic sites,with Ru being highly dispersed over the support and the Ni phase,while also forming some small Ru particles.This manifests in a significant enhancement in the CH_(4)yield and the CH_(4)production kinetics during ICCU-Methanation(which mainly proceeds via formate intermediates),with 0.2 wt%Ru addition leading to the best results.This bimetallic DFM also shows high stability and a relatively good performance under an oxidizing CO_(2)capture atmosphere.The formation rate of CH_(4)during hydrogenation is then further validated via CFD modelling and the developed model is subsequently applied in the prediction of the effect of other parameters,including the inlet H_(2)concentration,inlet flow rate,dual-fu nction material weight,and reactor internal diameter.展开更多
In this study,Ni catalysts supported on Pr-doped Ce O_(2) are studied for the CO_(2) methanation reaction and the effect of Pr doping on the physicochemical properties and the catalytic performance is thoroughly evalu...In this study,Ni catalysts supported on Pr-doped Ce O_(2) are studied for the CO_(2) methanation reaction and the effect of Pr doping on the physicochemical properties and the catalytic performance is thoroughly evaluated.It is shown,that Pr^(3+)ions can substitute Ce^(4+)ones in the support lattice,thereby introducing a high population of oxygen vacancies,which act as active sites for CO_(2) chemisorption.Pr doping can also act to reduce the crystallite size of metallic Ni,thus promoting the active metal dispersion.Catalytic performance evaluation evidences the promoting effect of low Pr loadings(5 at%and 10 at%)towards a higher catalytic activity and lower CO_(2) activation energy.On the other hand,higher Pr contents negate the positive effects on the catalytic activity by decreasing the oxygen vacancy population,thereby creating a volcano-type trend towards an optimum amount of aliovalent substitution.展开更多
基金support of this work by the project“Development of new innovative low carbon energy technologies to improve excellence in the Region of Western Macedonia”(MIS 5047197),which is implemented under the Action“Reinforcement of the Research and Innovation Infrastructure”funded by the Operational Program“Competitiveness,Entrepreneurship and Innovation”(NSRF 2014-2020)co-financed by Greece and the European Union(European Regional Development Fund)+4 种基金the Hellenic Foundation for Research and Innovation(HFRI)for supporting this research work under the 3~(rd)Call for HFRI PhD Fellowships(Fellowship Number:6033)the support of ELECMI-LMA nodeNanbiosis ICTSsfunded by the Swiss National Science Foundation(Grant:206021_189629)the Research Council of Norway(Grant:296087)。
文摘Herein,the effect of the Ru:Ni bimetallic composition in dual-function materials(DFMs)for the integrated CO_(2)capture and methanation process(ICCU-Methanation)is systematically evaluated and combined with a thorough material characterization,as well as a mechanistic(in-situ diffuse reflectance infrared fourier-transform spectroscopy(in-situ DRIFTS))and computational(computational fluid dynamics(CFD)modelling)investigation,in order to improve the performance of Ni-based DFMs.The bimetallic DFMs are comprised of a main Ni active metallic phase(20 wt%)and are modified with low Ru loadings in the 0.1-1 wt%range(to keep the material cost low),supported on Na_(2)O/Al_(2)O_(3).It is shown that the addition of even a very low Ru loading(0.1-0.2 wt%)can drastically improve the material reducibility,exposing a significantly higher amount of surface-active metallic sites,with Ru being highly dispersed over the support and the Ni phase,while also forming some small Ru particles.This manifests in a significant enhancement in the CH_(4)yield and the CH_(4)production kinetics during ICCU-Methanation(which mainly proceeds via formate intermediates),with 0.2 wt%Ru addition leading to the best results.This bimetallic DFM also shows high stability and a relatively good performance under an oxidizing CO_(2)capture atmosphere.The formation rate of CH_(4)during hydrogenation is then further validated via CFD modelling and the developed model is subsequently applied in the prediction of the effect of other parameters,including the inlet H_(2)concentration,inlet flow rate,dual-fu nction material weight,and reactor internal diameter.
基金support of this work by the project“Development of new innovative low carbon energy technologies to improve excellence in the Region of Western Macedonia”(MIS 5047197)which is implemented under the Action“Reinforcement of the Research and Innovation Infrastructure”funded by the Operational Program“Competitiveness,Entrepreneurship and Innovation”(NSRF 2014-2020)co-financed by Greece and the European Union(European Regional Development Fund)。
文摘In this study,Ni catalysts supported on Pr-doped Ce O_(2) are studied for the CO_(2) methanation reaction and the effect of Pr doping on the physicochemical properties and the catalytic performance is thoroughly evaluated.It is shown,that Pr^(3+)ions can substitute Ce^(4+)ones in the support lattice,thereby introducing a high population of oxygen vacancies,which act as active sites for CO_(2) chemisorption.Pr doping can also act to reduce the crystallite size of metallic Ni,thus promoting the active metal dispersion.Catalytic performance evaluation evidences the promoting effect of low Pr loadings(5 at%and 10 at%)towards a higher catalytic activity and lower CO_(2) activation energy.On the other hand,higher Pr contents negate the positive effects on the catalytic activity by decreasing the oxygen vacancy population,thereby creating a volcano-type trend towards an optimum amount of aliovalent substitution.
