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Mechanistic insights into copper removal by pyrolytic tire char through equilibrium studies / Augustine Quek in Industrial & engineering chemistry research, Vol. 49 N° 10 (Mai 2010) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 49 N° 10 (Mai 2010) . - pp. 4528–4534 Titre : Mechanistic insights into copper removal by pyrolytic tire char through equilibrium studies Type de document : texte imprimé Auteurs : Augustine Quek, Auteur ; Xiu-Song Zhao, Auteur ; Rajasekhar Balasubramanian, Auteur Année de publication : 2010 Article en page(s) : pp. 4528–4534 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : adsorptive  Copper Résumé : This study showed that copper(II) can be removed from aqueous solution by activated pyrolytic tire char in three mechanistically distinct ways. On the basis of equilibrium studies, the mechanisms involved in the adsorptive removal of copper(II), namely, precipitation, surface adsorption, and pore diffusion, were elucidated. Precipitation of copper(II) resulted from changes in the solution pH to neutral levels. This was attributed to amphoteric zinc oxide on the char surface, formed during production of the pyrolytic char. Surface adsorption was revealed by X-ray photoelectron spectroscopy data, which showed a significant increase in copper(II) on the char surface after shaking in the copper solution. This surface adsorption took place despite the relatively low surface area and porosity of the char. However, some cracks and fissures were found to exist in the char that can trap small species such as copper ions. These trapped copper species were partially recovered by microwave-assisted acid digestion of the char. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901289e [article] Mechanistic insights into copper removal by pyrolytic tire char through equilibrium studies [texte imprimé] / Augustine Quek, Auteur ; Xiu-Song Zhao, Auteur ; Rajasekhar Balasubramanian, Auteur . - 2010 . - pp. 4528–4534. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 10 (Mai 2010) . - pp. 4528–4534 Mots-clés : adsorptive  Copper Résumé : This study showed that copper(II) can be removed from aqueous solution by activated pyrolytic tire char in three mechanistically distinct ways. On the basis of equilibrium studies, the mechanisms involved in the adsorptive removal of copper(II), namely, precipitation, surface adsorption, and pore diffusion, were elucidated. Precipitation of copper(II) resulted from changes in the solution pH to neutral levels. This was attributed to amphoteric zinc oxide on the char surface, formed during production of the pyrolytic char. Surface adsorption was revealed by X-ray photoelectron spectroscopy data, which showed a significant increase in copper(II) on the char surface after shaking in the copper solution. This surface adsorption took place despite the relatively low surface area and porosity of the char. However, some cracks and fissures were found to exist in the char that can trap small species such as copper ions. These trapped copper species were partially recovered by microwave-assisted acid digestion of the char. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901289e

Role of hydrocarbon degrading bacteria serratia marcescens ACE2 and bacillus cereus ACE4 on corrosion of carbon steel API 5LX / Aruliah Rajasekar in Industrial & engineering chemistry research, Vol. 50 N° 17 (Septembre 2011) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 50 N° 17 (Septembre 2011) . - pp. 10041–10046 Titre : Role of hydrocarbon degrading bacteria serratia marcescens ACE2 and bacillus cereus ACE4 on corrosion of carbon steel API 5LX Type de document : texte imprimé Auteurs : Aruliah Rajasekar, Auteur ; Rajasekhar Balasubramanian, Auteur ; Joshua VM Kuma, Auteur Année de publication : 2011 Article en page(s) : pp. 10041–10046 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Corrosion  Carbon  Steel Résumé : This paper reports the microbiologically induced corrosion (MIC) and electrochemical behavior of carbon steel (API 5LX) in the presence of hydrocarbon-degrading bacteria Bacillus cereus ACE4 (a Gram-positive bacterium) and Serratia marcescens ACE2 (a Gram-negative bacterium). Weight loss studies and metallographic analysis of the metal API 5LX exposed to a simulated corrosive environment showed that the bacterium ACE4 caused severe pitting corrosion than that of bacterium ACE2. As part of biodegradation studies, the impact of aryl hydrocarbon hydroxylase (AHH) on diesel degradation was investigated along with reduction of total hydrocarbons. It was clearly observed that, during the biodegradation experiment in the presence of B. cereus ACE4, the content of the total hydrocarbons decreased significantly due to their metabolism induced by AHH enzymes when compared to S. marcescens ACE2. Degraded petroleum hydrocarbons (diesel) act as a good nutrient for bacteria, which in turn increases the proliferation of bacteria on the steel and determines the nature of corrosion. Metal oxides such as MnO2 and Fe2O3 were found as part of the corrosion products, indicating that the ACE4 bacterium is capable of converting the elements on the carbon steel (API 5LX) to their metal oxides and thus accelerating severe pitting corrosion on the surface of the pipeline networks. Overall, the study provides an insight into the microbiologically influenced corrosion of carbon steel API 5LX by two hydrocarbon-degrading bacteria in diesel fuel/water mixtures. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie200709q [article] Role of hydrocarbon degrading bacteria serratia marcescens ACE2 and bacillus cereus ACE4 on corrosion of carbon steel API 5LX [texte imprimé] / Aruliah Rajasekar, Auteur ; Rajasekhar Balasubramanian, Auteur ; Joshua VM Kuma, Auteur . - 2011 . - pp. 10041–10046. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 50 N° 17 (Septembre 2011) . - pp. 10041–10046 Mots-clés : Corrosion  Carbon  Steel Résumé : This paper reports the microbiologically induced corrosion (MIC) and electrochemical behavior of carbon steel (API 5LX) in the presence of hydrocarbon-degrading bacteria Bacillus cereus ACE4 (a Gram-positive bacterium) and Serratia marcescens ACE2 (a Gram-negative bacterium). Weight loss studies and metallographic analysis of the metal API 5LX exposed to a simulated corrosive environment showed that the bacterium ACE4 caused severe pitting corrosion than that of bacterium ACE2. As part of biodegradation studies, the impact of aryl hydrocarbon hydroxylase (AHH) on diesel degradation was investigated along with reduction of total hydrocarbons. It was clearly observed that, during the biodegradation experiment in the presence of B. cereus ACE4, the content of the total hydrocarbons decreased significantly due to their metabolism induced by AHH enzymes when compared to S. marcescens ACE2. Degraded petroleum hydrocarbons (diesel) act as a good nutrient for bacteria, which in turn increases the proliferation of bacteria on the steel and determines the nature of corrosion. Metal oxides such as MnO2 and Fe2O3 were found as part of the corrosion products, indicating that the ACE4 bacterium is capable of converting the elements on the carbon steel (API 5LX) to their metal oxides and thus accelerating severe pitting corrosion on the surface of the pipeline networks. Overall, the study provides an insight into the microbiologically influenced corrosion of carbon steel API 5LX by two hydrocarbon-degrading bacteria in diesel fuel/water mixtures. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie200709q