Documents disponibles écrits par cet auteur

Effect of electrolyte solutions on the adsorption of surfactants at PTFE−water interface / Nihar Ranjan Biswal in Industrial & engineering chemistry research, Vol. 49 N° 15 (Août 2010) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 49 N° 15 (Août 2010) . - pp 7060–7067 Titre : Effect of electrolyte solutions on the adsorption of surfactants at PTFE−water interface Type de document : texte imprimé Auteurs : Nihar Ranjan Biswal, Auteur ; Santanu Paria, Auteur Année de publication : 2010 Article en page(s) : pp 7060–7067 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Electrolyte  Adsorption  ionic  PTFE  water. Résumé : Adsorption of ionic and nonionic surfactants on low surface energy hydrophobic PTFE−water interfaces in the absence and presence of electrolytes have been studied here. The objective of this study is to see the surfactant adsorption behavior in the presence of electrolytes that may reduce the consumption of surfactants. The kinetics of adsorption fits well pseudo-second-order kinetic model for the three surfactants studied here. Adsorption isotherms of TX-100 follow Langmuir type, whereas sodium dodecylbenzene sulfonate (SDBS) and cetylpyridinium bromide (CPB) follow Freundlich type. However, in the presence of electrolytes both the ionic surfactants show better fitting with Langmuir type isotherm. The effect of electrolytes on the surfactant concentration far below the CMC shows there is a linear increase in amount adsorbed with the increase in ionic strength of the electrolyte mainly due to reduction in headgroup repulsion and finally reaches a plateau level when the equilibrium concentration reaches CMC at that electrolyte concentration. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie100812k [article] Effect of electrolyte solutions on the adsorption of surfactants at PTFE−water interface [texte imprimé] / Nihar Ranjan Biswal, Auteur ; Santanu Paria, Auteur . - 2010 . - pp 7060–7067. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 15 (Août 2010) . - pp 7060–7067 Mots-clés : Electrolyte  Adsorption  ionic  PTFE  water. Résumé : Adsorption of ionic and nonionic surfactants on low surface energy hydrophobic PTFE−water interfaces in the absence and presence of electrolytes have been studied here. The objective of this study is to see the surfactant adsorption behavior in the presence of electrolytes that may reduce the consumption of surfactants. The kinetics of adsorption fits well pseudo-second-order kinetic model for the three surfactants studied here. Adsorption isotherms of TX-100 follow Langmuir type, whereas sodium dodecylbenzene sulfonate (SDBS) and cetylpyridinium bromide (CPB) follow Freundlich type. However, in the presence of electrolytes both the ionic surfactants show better fitting with Langmuir type isotherm. The effect of electrolytes on the surfactant concentration far below the CMC shows there is a linear increase in amount adsorbed with the increase in ionic strength of the electrolyte mainly due to reduction in headgroup repulsion and finally reaches a plateau level when the equilibrium concentration reaches CMC at that electrolyte concentration. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie100812k

Rheological behavior of pyrophyllite − water slurry in the presence of anionic, cationic, and nonionic surfactants / Himanshu Desai in Industrial & engineering chemistry research, Vol. 49 N° 11 (Juin 2010) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 49 N° 11 (Juin 2010) . - pp. 5400–5406 Titre : Rheological behavior of pyrophyllite − water slurry in the presence of anionic, cationic, and nonionic surfactants Type de document : texte imprimé Auteurs : Himanshu Desai, Auteur ; Nihar Ranjan Biswal, Auteur ; Santanu Paria, Auteur Année de publication : 2010 Article en page(s) : pp. 5400–5406 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : surfactants  Anionic  Cationic Résumé : The rheological behavior of pyrophyllite−water clay slurry has been studied in the presence of three different types of surfactants: anionic, cationic, and nonionic. The slurry is non-Newtonian and thixotropic in nature, and the hysteresis area increases with increasing clay concentration. In the presence of acidic pH, surface potential is low and viscosity is high; the opposite is true for alkaline pH. The rheological behavior is different in the presence of three surfactants. The viscosity highly depends on the types of surfactant adsorbed on the clay surface and surface potential after the adsorption. The d(001) lattice spacing of the pyrophyllite clay does not change after the adsorption of surfactants, indicating that the surfactants are not adsorbing inside the clay spacing. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901643s [article] Rheological behavior of pyrophyllite − water slurry in the presence of anionic, cationic, and nonionic surfactants [texte imprimé] / Himanshu Desai, Auteur ; Nihar Ranjan Biswal, Auteur ; Santanu Paria, Auteur . - 2010 . - pp. 5400–5406. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 11 (Juin 2010) . - pp. 5400–5406 Mots-clés : surfactants  Anionic  Cationic Résumé : The rheological behavior of pyrophyllite−water clay slurry has been studied in the presence of three different types of surfactants: anionic, cationic, and nonionic. The slurry is non-Newtonian and thixotropic in nature, and the hysteresis area increases with increasing clay concentration. In the presence of acidic pH, surface potential is low and viscosity is high; the opposite is true for alkaline pH. The rheological behavior is different in the presence of three surfactants. The viscosity highly depends on the types of surfactant adsorbed on the clay surface and surface potential after the adsorption. The d(001) lattice spacing of the pyrophyllite clay does not change after the adsorption of surfactants, indicating that the surfactants are not adsorbing inside the clay spacing. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901643s

Wetting of PTFE and glass surfaces by aqueous solutions of cationic and anionic double - chain surfactants / Nihar Ranjan Biswal in Industrial & engineering chemistry research, Vol. 51 N° 30 (Août 2012) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10172–10178 Titre : Wetting of PTFE and glass surfaces by aqueous solutions of cationic and anionic double - chain surfactants Type de document : texte imprimé Auteurs : Nihar Ranjan Biswal, Auteur ; Santanu Paria, Auteur Année de publication : 2012 Article en page(s) : pp. 10172–10178 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Wetting  Glass  Aqueous  solutions  Cationic  Anionic Résumé : The wetting of hydrophobic and hydrophilic solid surfaces by surfactant solutions is an important research topic recently because of its profound practical applications. The wettability of two double-chain surfactants (cationic, didodecyldimethylammonium bromide or DDAB, and anionic, aerosol OT or AOT) solutions on poly(tetrafluoroethylene) (PTFE) and glass surfaces has been investigated here. Different physicochemical parameters such as critical micelle concentration (CMC) and surface tension, contact angle, surface excess at air–water and solid-water interfaces, work of adhesion, and free energy of wetting have been estimated for two double-chain surfactants solutions and compared with the reported results of single-chain surfactants. The double-chain surfactant solutions showed maximum lowering of surface tension values (24.36 and 26.35 mN/m for DDAB and AOT, respectively) and a change in contact angle values from pure water on PTFE (38° for DDAB and AOT) and glass (26.5 and 24° for DDAB and AOT, respectively) surfaces compared to the conventionally studied single-chain surfactants. The surfactant molecules mostly formed a monolayer adsorption on both surfaces during the wetting process. The surface excess values of both of the surfactants on PTFE–water and glass–water interfaces are 0.759 and 0.850 times lower than that of the air–water interface, respectively. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie301198k [article] Wetting of PTFE and glass surfaces by aqueous solutions of cationic and anionic double - chain surfactants [texte imprimé] / Nihar Ranjan Biswal, Auteur ; Santanu Paria, Auteur . - 2012 . - pp. 10172–10178. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10172–10178 Mots-clés : Wetting  Glass  Aqueous  solutions  Cationic  Anionic Résumé : The wetting of hydrophobic and hydrophilic solid surfaces by surfactant solutions is an important research topic recently because of its profound practical applications. The wettability of two double-chain surfactants (cationic, didodecyldimethylammonium bromide or DDAB, and anionic, aerosol OT or AOT) solutions on poly(tetrafluoroethylene) (PTFE) and glass surfaces has been investigated here. Different physicochemical parameters such as critical micelle concentration (CMC) and surface tension, contact angle, surface excess at air–water and solid-water interfaces, work of adhesion, and free energy of wetting have been estimated for two double-chain surfactants solutions and compared with the reported results of single-chain surfactants. The double-chain surfactant solutions showed maximum lowering of surface tension values (24.36 and 26.35 mN/m for DDAB and AOT, respectively) and a change in contact angle values from pure water on PTFE (38° for DDAB and AOT) and glass (26.5 and 24° for DDAB and AOT, respectively) surfaces compared to the conventionally studied single-chain surfactants. The surfactant molecules mostly formed a monolayer adsorption on both surfaces during the wetting process. The surface excess values of both of the surfactants on PTFE–water and glass–water interfaces are 0.759 and 0.850 times lower than that of the air–water interface, respectively. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie301198k

Wetting of TX-100 and igepal CO-630 surfactants on a PTFE surface / Nihar Ranjan Biswal in Industrial & engineering chemistry research, Vol. 50 N° 10 (Mai 2011) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 50 N° 10 (Mai 2011) . - pp. 6138-6145 Titre : Wetting of TX-100 and igepal CO-630 surfactants on a PTFE surface Type de document : texte imprimé Auteurs : Nihar Ranjan Biswal, Auteur ; Santanu Paria, Auteur Année de publication : 2011 Article en page(s) : pp. 6138-6145 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Surfactant  Wetting Résumé : Nonionic surfactants are advantageous in a diversified range of applications from household cleaners, laundry detergents, and shampoo to paints, coatings, and food emulsifiers because of their low CMC and surface tension values over the ionic surfactants. Nonionic surfactants, in general, are very useful in mixed surfactant systems because of their electrical neutrality. Among the similar class of nonionic surfactants, structural difference is important in the performance. In this study, we report on the adsorption and wetting behavior of two nonionic surfactants (TX-100 and Igepal CO-630) having the same head group but structurally different tail groups. The kinetics of adsorption follows a pseudo-second-order kinetic model and a Langmuir-type isotherm for both the surfactants. The change in contact angle with the concentration of surfactant follows a trend similar to that for adsorption onto a PTFE surface. At low surfactant concentration, Igepal CO-630 shows a slightly higher adsorption density and better wetting properties than TX-100. Both surfactants show lower adsorption densities at the PTFE-water interface than at the air-water interface. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=24158913 [article] Wetting of TX-100 and igepal CO-630 surfactants on a PTFE surface [texte imprimé] / Nihar Ranjan Biswal, Auteur ; Santanu Paria, Auteur . - 2011 . - pp. 6138-6145. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 50 N° 10 (Mai 2011) . - pp. 6138-6145 Mots-clés : Surfactant  Wetting Résumé : Nonionic surfactants are advantageous in a diversified range of applications from household cleaners, laundry detergents, and shampoo to paints, coatings, and food emulsifiers because of their low CMC and surface tension values over the ionic surfactants. Nonionic surfactants, in general, are very useful in mixed surfactant systems because of their electrical neutrality. Among the similar class of nonionic surfactants, structural difference is important in the performance. In this study, we report on the adsorption and wetting behavior of two nonionic surfactants (TX-100 and Igepal CO-630) having the same head group but structurally different tail groups. The kinetics of adsorption follows a pseudo-second-order kinetic model and a Langmuir-type isotherm for both the surfactants. The change in contact angle with the concentration of surfactant follows a trend similar to that for adsorption onto a PTFE surface. At low surfactant concentration, Igepal CO-630 shows a slightly higher adsorption density and better wetting properties than TX-100. Both surfactants show lower adsorption densities at the PTFE-water interface than at the air-water interface. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=24158913