Documents disponibles écrits par cet auteur

Modification of carbon nanotubes for H2S sorption / Ali Mohamadalizadeh in Industrial & engineering chemistry research, Vol. 50 N° 13 (Juillet 2011) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 50 N° 13 (Juillet 2011) . - pp. 8050-8057 Titre : Modification of carbon nanotubes for H2S sorption Type de document : texte imprimé Auteurs : Ali Mohamadalizadeh, Auteur ; Jafar Towfighi, Auteur ; Alimorad Rashidi, Auteur Année de publication : 2011 Article en page(s) : pp. 8050-8057 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Sorption  Hydrogen  sulfides Résumé : Multiwall carbon nanotubes (MWNTs), prepared with methane as carbon source through the chemical vapor deposition (CVD) method at 900 °C, were functionalized to have amino and amido functional groups and then deposited with tungsten (W) nanoparticles. Pure H2S sorption on MWNTs, MWNTs loaded with W, functionalized MWNTs, and activated carbon (prepared from walnut shell) was investigated at 20 °C and a pressure range of 1-10 bar. X-ray diffraction, transmission and scanning electron microscopies, Raman spectroscopy, ASAP, inductively coupled plasma, and temperature-programmed reduction analysis were performed to determine the properties of the sorbent. The presence of amino functional groups was found to increase the sorption capacity of MWNTs, while the decoration of MWNTs with W nanoparticles decreased the sorption capacity. Results of the research revealed that functionalized MWNTs have a higher H2S sorption capacity than activated carbon. Langmuir, Freundlich, Unilan, Sips, and Toth isotherm models were used for a mathematical description of hydrogen sulfide equilibrium adsorption, and the experimental data for all four adsorbents showed the best accordance with the Freundlich model, while the Unilan model had the least accordance with the experimental data obtained for adsorbents based on MWNTs. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=24332130 [article] Modification of carbon nanotubes for H2S sorption [texte imprimé] / Ali Mohamadalizadeh, Auteur ; Jafar Towfighi, Auteur ; Alimorad Rashidi, Auteur . - 2011 . - pp. 8050-8057. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 50 N° 13 (Juillet 2011) . - pp. 8050-8057 Mots-clés : Sorption  Hydrogen  sulfides Résumé : Multiwall carbon nanotubes (MWNTs), prepared with methane as carbon source through the chemical vapor deposition (CVD) method at 900 °C, were functionalized to have amino and amido functional groups and then deposited with tungsten (W) nanoparticles. Pure H2S sorption on MWNTs, MWNTs loaded with W, functionalized MWNTs, and activated carbon (prepared from walnut shell) was investigated at 20 °C and a pressure range of 1-10 bar. X-ray diffraction, transmission and scanning electron microscopies, Raman spectroscopy, ASAP, inductively coupled plasma, and temperature-programmed reduction analysis were performed to determine the properties of the sorbent. The presence of amino functional groups was found to increase the sorption capacity of MWNTs, while the decoration of MWNTs with W nanoparticles decreased the sorption capacity. Results of the research revealed that functionalized MWNTs have a higher H2S sorption capacity than activated carbon. Langmuir, Freundlich, Unilan, Sips, and Toth isotherm models were used for a mathematical description of hydrogen sulfide equilibrium adsorption, and the experimental data for all four adsorbents showed the best accordance with the Freundlich model, while the Unilan model had the least accordance with the experimental data obtained for adsorbents based on MWNTs. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=24332130

Oxygen separation from air by four-bed pressure swing adsorption / Masoud Mofarahi in Industrial & engineering chemistry research, Vol. 48 N° 11 (Juin 2009) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 48 N° 11 (Juin 2009) . - pp. 5439–5444 Titre : Oxygen separation from air by four-bed pressure swing adsorption Type de document : texte imprimé Auteurs : Masoud Mofarahi, Auteur ; Jafar Towfighi, Auteur ; Leila Fathi, Auteur Année de publication : 2009 Article en page(s) : pp. 5439–5444 Note générale : Chemical engineering Langues : Anglais (eng) Mots-clés : Pressure  swing  adsorption  Zeolite  5A  Oxygen  separation Résumé : A study on a four-bed seven-step pressure swing adsorption (PSA) using zeolite 5A was performed experimentally and theoretically for separation of oxygen from air. In this process the steps of feed pressurization, production, blowdown, purge, pressure equalization (two steps), and product pressurization are included in a cycle. The effects of various operating parameters such as adsorption pressure, cycle time, production rate, and purge rate on the product purity and recovery were investigated experimentally. Oxygen purity and recovery both increase when adsorption pressure increases. For most of the experiments at the highest purge rate, a higher purity of oxygen is obtained, but the recovery of oxygen is reduced. Oxygen recovery increases as production rate increases while the purge flow rate remains constant. It was observed that increasing the cycle time increases the performance of the process. An equilibrium based isothermal model in conjunction with an LDF (linear driving force) approximation was employed to simulate process performance. Comparison of the results obtained from the experiments and simulation results shows reasonable agreement. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie801805k [article] Oxygen separation from air by four-bed pressure swing adsorption [texte imprimé] / Masoud Mofarahi, Auteur ; Jafar Towfighi, Auteur ; Leila Fathi, Auteur . - 2009 . - pp. 5439–5444. Chemical engineering Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 48 N° 11 (Juin 2009) . - pp. 5439–5444 Mots-clés : Pressure  swing  adsorption  Zeolite  5A  Oxygen  separation Résumé : A study on a four-bed seven-step pressure swing adsorption (PSA) using zeolite 5A was performed experimentally and theoretically for separation of oxygen from air. In this process the steps of feed pressurization, production, blowdown, purge, pressure equalization (two steps), and product pressurization are included in a cycle. The effects of various operating parameters such as adsorption pressure, cycle time, production rate, and purge rate on the product purity and recovery were investigated experimentally. Oxygen purity and recovery both increase when adsorption pressure increases. For most of the experiments at the highest purge rate, a higher purity of oxygen is obtained, but the recovery of oxygen is reduced. Oxygen recovery increases as production rate increases while the purge flow rate remains constant. It was observed that increasing the cycle time increases the performance of the process. An equilibrium based isothermal model in conjunction with an LDF (linear driving force) approximation was employed to simulate process performance. Comparison of the results obtained from the experiments and simulation results shows reasonable agreement. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie801805k