Documents disponibles écrits par cet auteur

Analysis of equilibrium - based TSA processes for direct capture of CO2 from air / Ambarish R. Kulkarni in Industrial & engineering chemistry research, Vol. 51 N° 25 (Juin 2012) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 51 N° 25 (Juin 2012) . - pp. 8631–8645 Titre : Analysis of equilibrium - based TSA processes for direct capture of CO2 from air Type de document : texte imprimé Auteurs : Ambarish R. Kulkarni, Auteur ; David S. Sholl, Auteur Année de publication : 2012 Article en page(s) : pp. 8631–8645 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Adsorption  processes  Capture  CO2 Résumé : Direct capture of CO2 from air is a concept that, if successfully implemented, could lead to capture of CO2 from disperse sources. We have developed process models to consider the viability of adsorption-based air capture technologies. Our models focus on using an amino-modified silica adsorbent, TRI-PE-MCM-41, and a structured monolithic contactor unit. We have studied several different temperature swing adsorption processes using the purity of CO2 and annual product throughput as metrics for comparing process performance. This analysis identifies some of the operational parameters, adsorbent characteristics, and other factors that have a significant effect on the performance of the process. Using the total energy requirement of the process and available sources of energy, such as low pressure steam and electricity, we carry out an economic analysis to obtain a net operating cost for air capture of CO2. We identify a process with a daily throughput of 1.1 t CO2 at 88.5% purity using standard shipping container sized air capture units. The total energy required (6745 MJ/t CO2) is dominated by the parasitic losses—sensible heat requirements of the contactor (40%) and the adsorbent (28%) and not by the mechanical energy associated with air flow (5%). On the basis of our analysis of factors such as source of electricity, availability of low pressure steam, and geographic location, the net operating cost of capture is estimated to be $100/t CO2. These cost estimates do not include capital expenses necessary to construct or maintain the air capture units. Potential strategies for further reducing the energy and monetary cost of these processes are identified. Our analysis supports continued work to establish the technological and economic feasibility of adsorption-based air capture. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie300691c [article] Analysis of equilibrium - based TSA processes for direct capture of CO2 from air [texte imprimé] / Ambarish R. Kulkarni, Auteur ; David S. Sholl, Auteur . - 2012 . - pp. 8631–8645. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 51 N° 25 (Juin 2012) . - pp. 8631–8645 Mots-clés : Adsorption  processes  Capture  CO2 Résumé : Direct capture of CO2 from air is a concept that, if successfully implemented, could lead to capture of CO2 from disperse sources. We have developed process models to consider the viability of adsorption-based air capture technologies. Our models focus on using an amino-modified silica adsorbent, TRI-PE-MCM-41, and a structured monolithic contactor unit. We have studied several different temperature swing adsorption processes using the purity of CO2 and annual product throughput as metrics for comparing process performance. This analysis identifies some of the operational parameters, adsorbent characteristics, and other factors that have a significant effect on the performance of the process. Using the total energy requirement of the process and available sources of energy, such as low pressure steam and electricity, we carry out an economic analysis to obtain a net operating cost for air capture of CO2. We identify a process with a daily throughput of 1.1 t CO2 at 88.5% purity using standard shipping container sized air capture units. The total energy required (6745 MJ/t CO2) is dominated by the parasitic losses—sensible heat requirements of the contactor (40%) and the adsorbent (28%) and not by the mechanical energy associated with air flow (5%). On the basis of our analysis of factors such as source of electricity, availability of low pressure steam, and geographic location, the net operating cost of capture is estimated to be $100/t CO2. These cost estimates do not include capital expenses necessary to construct or maintain the air capture units. Potential strategies for further reducing the energy and monetary cost of these processes are identified. Our analysis supports continued work to establish the technological and economic feasibility of adsorption-based air capture. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie300691c

Assessment of a metal−organic framework membrane for gas separations using atomically detailed calculations: CO2, CH4, N2, H2 mixtures in MOF-5 / Seda Keskin in Industrial & engineering chemistry research, Vol. 48 N°2 (Janvier 2009) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 48 N°2 (Janvier 2009) . - p. 914–922 Titre : Assessment of a metal−organic framework membrane for gas separations using atomically detailed calculations: CO2, CH4, N2, H2 mixtures in MOF-5 Type de document : texte imprimé Auteurs : Seda Keskin, Auteur ; David S. Sholl, Auteur Année de publication : 2009 Article en page(s) : p. 914–922 Note générale : chemical engineering Langues : Anglais (eng) Mots-clés : Metal−Organic  Framework Résumé : Metal−organic frameworks (MOFs) have emerged as a fascinating alternative to more traditional nanoporous materials. Although hundreds of different MOF structures have been synthesized in powder form, little is currently known about the potential performance of MOFs for membrane-based separations. We have used atomistic calculations to predict the performance of a MOF membrane for separation of various gas mixtures in order to provide information for material selection in membrane design. Specifically, we investigated the performance of MOF-5 as a membrane for separation of CO2/CH4, CO2/H2, CO2/N2, CH4/H2, N2/H2, and N2/CH4 mixtures at room temperature. In every case, mixture effects play a crucial role in determining the membrane performance. Although the membrane selectivities predicted for MOF-5 are not large for the mixtures we studied, our result suggest that atomistic simulations will be a useful tool for considering the large number of MOF crystal structures that are known in order to seek membrane materials with more desirable characteristics. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie8010885 [article] Assessment of a metal−organic framework membrane for gas separations using atomically detailed calculations: CO2, CH4, N2, H2 mixtures in MOF-5 [texte imprimé] / Seda Keskin, Auteur ; David S. Sholl, Auteur . - 2009 . - p. 914–922. chemical engineering Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 48 N°2 (Janvier 2009) . - p. 914–922 Mots-clés : Metal−Organic  Framework Résumé : Metal−organic frameworks (MOFs) have emerged as a fascinating alternative to more traditional nanoporous materials. Although hundreds of different MOF structures have been synthesized in powder form, little is currently known about the potential performance of MOFs for membrane-based separations. We have used atomistic calculations to predict the performance of a MOF membrane for separation of various gas mixtures in order to provide information for material selection in membrane design. Specifically, we investigated the performance of MOF-5 as a membrane for separation of CO2/CH4, CO2/H2, CO2/N2, CH4/H2, N2/H2, and N2/CH4 mixtures at room temperature. In every case, mixture effects play a crucial role in determining the membrane performance. Although the membrane selectivities predicted for MOF-5 are not large for the mixtures we studied, our result suggest that atomistic simulations will be a useful tool for considering the large number of MOF crystal structures that are known in order to seek membrane materials with more desirable characteristics. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie8010885

Predictions of sulfur resistance in metal membranes for H2 purification using first - principles calculations / Ki Chul Kim in Industrial & engineering chemistry research, Vol. 51 N° 1 (Janvier 2012) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 51 N° 1 (Janvier 2012) . - pp. 301–309 Titre : Predictions of sulfur resistance in metal membranes for H2 purification using first - principles calculations Type de document : texte imprimé Auteurs : Ki Chul Kim, Auteur ; Sung Gu Kang, Auteur ; David S. Sholl, Auteur Année de publication : 2012 Article en page(s) : pp. 301–309 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Metal  membranes  Purification Résumé : Contamination of metal films by sulfur-containing compounds presents a major challenge to using metal membranes for H2 purification in processes involving large-scale gasification of coal or biomass. Formation of bulk sulfide phases in these applications is typically associated with irreversible loss of performance and ultimately membrane failure. The concept of using metal alloys to reduce sensitivity to sulfide formation has been explored in a variety of experiments, but development of alloys for this purpose has been hampered by a lack of thermodynamic data on formation of the relevant sulfide phases. We show that first principles calculations using density functional theory can be used to predict the formation of bulk sulfide phases from metal alloys under conditions that are relevant for operation of metal membranes. Our methods are illustrated by assessing the formation of sulfides for PdAg, PdAu, and PdCu alloys of all possible binary compositions. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie201888x [article] Predictions of sulfur resistance in metal membranes for H2 purification using first - principles calculations [texte imprimé] / Ki Chul Kim, Auteur ; Sung Gu Kang, Auteur ; David S. Sholl, Auteur . - 2012 . - pp. 301–309. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 51 N° 1 (Janvier 2012) . - pp. 301–309 Mots-clés : Metal  membranes  Purification Résumé : Contamination of metal films by sulfur-containing compounds presents a major challenge to using metal membranes for H2 purification in processes involving large-scale gasification of coal or biomass. Formation of bulk sulfide phases in these applications is typically associated with irreversible loss of performance and ultimately membrane failure. The concept of using metal alloys to reduce sensitivity to sulfide formation has been explored in a variety of experiments, but development of alloys for this purpose has been hampered by a lack of thermodynamic data on formation of the relevant sulfide phases. We show that first principles calculations using density functional theory can be used to predict the formation of bulk sulfide phases from metal alloys under conditions that are relevant for operation of metal membranes. Our methods are illustrated by assessing the formation of sulfides for PdAg, PdAu, and PdCu alloys of all possible binary compositions. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie201888x