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Cationic alkoxylated amine surfactant as a debonding agent for papers made of sulfite-bleached fibers / Pedram Fatehi 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. 749–754 Titre : Cationic alkoxylated amine surfactant as a debonding agent for papers made of sulfite-bleached fibers Type de document : texte imprimé Auteurs : Pedram Fatehi, Auteur ; Kevin C. Outhouse, Auteur ; Huining Xiao, Auteur Année de publication : 2009 Article en page(s) : p. 749–754 Note générale : chemical engenireeng Langues : Anglais (eng) Mots-clés : Sulfite-Bleached  --  Papers  Made Résumé : Today, there is a steadily increasing demand for the application of surfactants as debonding agents in tissue manufacturing. The work presented herein focused on evaluating the debonding ability of cationic alkoxylated amine surfactant on unrefined and refined fibers. The results showed that, as the dosage of the surfactant was increased to 10 mg/g on unrefined pulps, the adsorption of the surfactant on the fibers increased to 5 mg/g, and the tensile and burst indices of the papers made of the modified fibers decreased by as much as 12.6% and 14.9%, respectively. Also, the roughness, strain, and moisture content of the papers were enhanced, whereas the apparent density was reduced. Furthermore, the tear index of the papers increased upon the application of surfactant (10 mg/g) at the expense of reductions in tensile and burst indices, as well as the apparent density at any pressure applied in wet pressing. Also, as the pressure was increased, the surfactant impacted the fiber bonding more significantly. On the other hand, the application of surfactant (10 mg/g) somewhat increased the light scattering coefficient of the papers, regardless of the refining load. Furthermore, the adsorption of the surfactant on refined fibers increased with increasing refining load. However, the influence of the surfactant on the tear, tensile, and burst indices and the apparent density was impaired with increasing refining load. Also, the zero-span tensile index and brightness of the papers varied negligibly upon surfactant application. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie800929p [article] Cationic alkoxylated amine surfactant as a debonding agent for papers made of sulfite-bleached fibers [texte imprimé] / Pedram Fatehi, Auteur ; Kevin C. Outhouse, Auteur ; Huining Xiao, Auteur . - 2009 . - p. 749–754. chemical engenireeng Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 48 N°2 (Janvier 2009) . - p. 749–754 Mots-clés : Sulfite-Bleached  --  Papers  Made Résumé : Today, there is a steadily increasing demand for the application of surfactants as debonding agents in tissue manufacturing. The work presented herein focused on evaluating the debonding ability of cationic alkoxylated amine surfactant on unrefined and refined fibers. The results showed that, as the dosage of the surfactant was increased to 10 mg/g on unrefined pulps, the adsorption of the surfactant on the fibers increased to 5 mg/g, and the tensile and burst indices of the papers made of the modified fibers decreased by as much as 12.6% and 14.9%, respectively. Also, the roughness, strain, and moisture content of the papers were enhanced, whereas the apparent density was reduced. Furthermore, the tear index of the papers increased upon the application of surfactant (10 mg/g) at the expense of reductions in tensile and burst indices, as well as the apparent density at any pressure applied in wet pressing. Also, as the pressure was increased, the surfactant impacted the fiber bonding more significantly. On the other hand, the application of surfactant (10 mg/g) somewhat increased the light scattering coefficient of the papers, regardless of the refining load. Furthermore, the adsorption of the surfactant on refined fibers increased with increasing refining load. However, the influence of the surfactant on the tear, tensile, and burst indices and the apparent density was impaired with increasing refining load. Also, the zero-span tensile index and brightness of the papers varied negligibly upon surfactant application. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie800929p

Debonding performance of various cationic surfactants on networks made of bleached kraft fibers / Pedram Fatehi in Industrial & engineering chemistry research, Vol. 49 N° 22 (Novembre 2010) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp.11402–11407 Titre : Debonding performance of various cationic surfactants on networks made of bleached kraft fibers Type de document : texte imprimé Auteurs : Pedram Fatehi, Auteur ; Kevin C. Outhouse, Auteur ; Huining Xiao, Auteur Année de publication : 2011 Article en page(s) : pp.11402–11407 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Cationic  Fibers Résumé : Debonding agents are applied in the paper industry for various purposes, for example, to increase the softness of tissue paper. In this work, the debonding capacities of three cationic aliphatic ammonium surfactants and one alkoxylated amine surfactant on kraft fibers were determined. The results showed that the adsorption of the alkoxylated amine surfactant (AAS) was higher than that of others on the fibers, but a cationic cetyltrimethyl ammonium surfactant (cetyltrimethyl ammonium bromide, CAB) was the most effective debonding agent, probably because of its relatively long hydrophobic chain. By applying CAB at levels of up to 20 mg/g, the tensile and burst indices were reduced by 37% and 41%, respectively. By applying AAS at levels of up to 20 mg/g, the tensile and burst indices of the networks were reduced by 18.6%, and 14.2%, respectively. The tear index of the fiber networks negligibly changed upon application of AAS, but increased by 19% upon application of CAB. The strain of the fiber networks prior to rupturing increased upon application of AAS, whereas it decreased upon application of CAB, which implies that the surfactants have different debonding mechanisms. The debonding efficiency of CAB was independent of both the refining revolutions and basis weights of the fiber networks. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie101442p [article] Debonding performance of various cationic surfactants on networks made of bleached kraft fibers [texte imprimé] / Pedram Fatehi, Auteur ; Kevin C. Outhouse, Auteur ; Huining Xiao, Auteur . - 2011 . - pp.11402–11407. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp.11402–11407 Mots-clés : Cationic  Fibers Résumé : Debonding agents are applied in the paper industry for various purposes, for example, to increase the softness of tissue paper. In this work, the debonding capacities of three cationic aliphatic ammonium surfactants and one alkoxylated amine surfactant on kraft fibers were determined. The results showed that the adsorption of the alkoxylated amine surfactant (AAS) was higher than that of others on the fibers, but a cationic cetyltrimethyl ammonium surfactant (cetyltrimethyl ammonium bromide, CAB) was the most effective debonding agent, probably because of its relatively long hydrophobic chain. By applying CAB at levels of up to 20 mg/g, the tensile and burst indices were reduced by 37% and 41%, respectively. By applying AAS at levels of up to 20 mg/g, the tensile and burst indices of the networks were reduced by 18.6%, and 14.2%, respectively. The tear index of the fiber networks negligibly changed upon application of AAS, but increased by 19% upon application of CAB. The strain of the fiber networks prior to rupturing increased upon application of AAS, whereas it decreased upon application of CAB, which implies that the surfactants have different debonding mechanisms. The debonding efficiency of CAB was independent of both the refining revolutions and basis weights of the fiber networks. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie101442p

Optimizing the poly ethylene oxide flocculation process for isolating lignin of prehydrolysis liquor of a kraft - based dissolving pulp production process / Haiqiang Shi in Industrial & engineering chemistry research, Vol. 51 N° 14 (Avril 2012) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 51 N° 14 (Avril 2012) . - pp. 5330-5335 Titre : Optimizing the poly ethylene oxide flocculation process for isolating lignin of prehydrolysis liquor of a kraft - based dissolving pulp production process Type de document : texte imprimé Auteurs : Haiqiang Shi, Auteur ; Pedram Fatehi, Auteur ; Huining Xiao, Auteur Année de publication : 2012 Article en page(s) : pp. 5330-5335 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Manufacturing  process  Flocculation  Optimization Résumé : In this work, poly ethylene oxide (PEO) with various molecular weights (MW)s was employed to separate the lignin ot prehydrolysis liquor (PHL) ot a kraft-based dissolving pulp process. The results revealed that, the higher the MW and concentration of PEO in the PHL at pH 2, the higher are the removals of lignin and chemical oxygen demand (COD) but with a marginal removal of sugars. Alternatively, poly aluminum chloride (PAC) (200 mg/L) and PEO (8 MDa MW) (200 mg/L) were employed in a dual polymer system to extract the lignin, and the PAC/PEO system (MWs of 2 kDa/8 MDa) was more effective than the PEO/PEO system (MWs of 0.1 MDa/8 MDa) in removing lignin and COD of PHL. The maximum lignin, sugar, and COD removals were 46%, 18.8%, and 32%, respectively, under the conditions of 400 mg/g PEO (with a MW of 8 MDa) at pH 2 and room temperature in a singular PEO system. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25783442 [article] Optimizing the poly ethylene oxide flocculation process for isolating lignin of prehydrolysis liquor of a kraft - based dissolving pulp production process [texte imprimé] / Haiqiang Shi, Auteur ; Pedram Fatehi, Auteur ; Huining Xiao, Auteur . - 2012 . - pp. 5330-5335. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 51 N° 14 (Avril 2012) . - pp. 5330-5335 Mots-clés : Manufacturing  process  Flocculation  Optimization Résumé : In this work, poly ethylene oxide (PEO) with various molecular weights (MW)s was employed to separate the lignin ot prehydrolysis liquor (PHL) ot a kraft-based dissolving pulp process. The results revealed that, the higher the MW and concentration of PEO in the PHL at pH 2, the higher are the removals of lignin and chemical oxygen demand (COD) but with a marginal removal of sugars. Alternatively, poly aluminum chloride (PAC) (200 mg/L) and PEO (8 MDa MW) (200 mg/L) were employed in a dual polymer system to extract the lignin, and the PAC/PEO system (MWs of 2 kDa/8 MDa) was more effective than the PEO/PEO system (MWs of 0.1 MDa/8 MDa) in removing lignin and COD of PHL. The maximum lignin, sugar, and COD removals were 46%, 18.8%, and 32%, respectively, under the conditions of 400 mg/g PEO (with a MW of 8 MDa) at pH 2 and room temperature in a singular PEO system. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25783442

Treatment of fractionated fibers with various cationic-modified poly(vinyl alcohols) and Its iImpact on paper properties / Pedram Fatehi in Industrial & engineering chemistry research, Vol. 48 N° 23 (Décembre 2009) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 48 N° 23 (Décembre 2009) . - pp. 10485–10490 Titre : Treatment of fractionated fibers with various cationic-modified poly(vinyl alcohols) and Its iImpact on paper properties Type de document : texte imprimé Auteurs : Pedram Fatehi, Auteur ; Jeffery E. Ward, Auteur ; Huining Xiao, Auteur Année de publication : 2010 Article en page(s) : pp. 10485–10490 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Treatment--Fractionated  Fibers--Various--Cationic-Modified--Poly(vinyl  alcohols--Impact--Paper  Properties Résumé : In this work, the effects of various high molecular weight cationic poly(vinyl alcohols), CPVAs, on the fiber morphology and the properties of papers made from fractionated refined fibers were investigated. At first, bleached sulfite fibers were refined under various revolutions and then refined fibers were fractionated under various time intervals to obtain refined fibers with a similar fiber length and fines content. Then, 20 mg/g CPVAs with various charge densities was adsorbed on the fractionated refined fibers prior to making hand sheets. The results showed that the lower the charge density of CPVA, the higher the effectiveness of CPVA in improving the paper strength at any refining revolution. The reasons for such a phenomenon were perhaps the different configurations of CPVAs on the surface of the fibers and the different adhesion/repulsion forces developed between CPVA-modified fibers in hand sheets. Also, by reducing the freeness of the fractionated fibers (increasing the refining revolutions), the effect of CPVA in improving the paper strength was reduced. In this case, the CPVAs tended to cover the fibrils on the fiber surface, which was demonstrated by SEM observations, thus reducing the contact area of the fractionated refined fibers. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900999n [article] Treatment of fractionated fibers with various cationic-modified poly(vinyl alcohols) and Its iImpact on paper properties [texte imprimé] / Pedram Fatehi, Auteur ; Jeffery E. Ward, Auteur ; Huining Xiao, Auteur . - 2010 . - pp. 10485–10490. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 48 N° 23 (Décembre 2009) . - pp. 10485–10490 Mots-clés : Treatment--Fractionated  Fibers--Various--Cationic-Modified--Poly(vinyl  alcohols--Impact--Paper  Properties Résumé : In this work, the effects of various high molecular weight cationic poly(vinyl alcohols), CPVAs, on the fiber morphology and the properties of papers made from fractionated refined fibers were investigated. At first, bleached sulfite fibers were refined under various revolutions and then refined fibers were fractionated under various time intervals to obtain refined fibers with a similar fiber length and fines content. Then, 20 mg/g CPVAs with various charge densities was adsorbed on the fractionated refined fibers prior to making hand sheets. The results showed that the lower the charge density of CPVA, the higher the effectiveness of CPVA in improving the paper strength at any refining revolution. The reasons for such a phenomenon were perhaps the different configurations of CPVAs on the surface of the fibers and the different adhesion/repulsion forces developed between CPVA-modified fibers in hand sheets. Also, by reducing the freeness of the fractionated fibers (increasing the refining revolutions), the effect of CPVA in improving the paper strength was reduced. In this case, the CPVAs tended to cover the fibrils on the fiber surface, which was demonstrated by SEM observations, thus reducing the contact area of the fractionated refined fibers. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900999n