Documents disponibles écrits par cet auteur

Influence of water quality on the efficiency of retention aids systems for the paper industry / Ruth Ordóñez 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. 10247–10252 Titre : Influence of water quality on the efficiency of retention aids systems for the paper industry Type de document : texte imprimé Auteurs : Ruth Ordóñez, Auteur ; Daphne Hermosilla, Auteur ; Elena de la Fuente, Auteur Année de publication : 2010 Article en page(s) : pp. 10247–10252 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Influence--Water--Quality--Efficiency--Retention--Systems--Paper--Industry Résumé : It has been reported that about 10−15% of the fresh water intake in a paper mill is used for feeding and diluting retention aids, so significant savings could be achieved by replacing fresh water with process water. Water from different sources and qualities—fresh water, the outflow from an internal ultrafiltration placed in the machine circuit of a paper mill, and water from a membrane bioreactor used to treat the final effluent of this paper mill—were used to prepare a dual retention system consisting of a cationic polyacrylamide and bentonite. While the behavior of bentonite was not significantly affected by the quality of the water used in its preparation, the efficiency of the cationic polyacrylamide was reduced to about 12% when it was prepared with water with high anionic trash content and conductivity as a result of a partial neutralization of the charged groups. The effect of nonionic chemical oxygen demand on the efficiency of the polymer was negligible. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9010029 [article] Influence of water quality on the efficiency of retention aids systems for the paper industry [texte imprimé] / Ruth Ordóñez, Auteur ; Daphne Hermosilla, Auteur ; Elena de la Fuente, Auteur . - 2010 . - pp. 10247–10252. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 48 N° 23 (Décembre 2009) . - pp. 10247–10252 Mots-clés : Influence--Water--Quality--Efficiency--Retention--Systems--Paper--Industry Résumé : It has been reported that about 10−15% of the fresh water intake in a paper mill is used for feeding and diluting retention aids, so significant savings could be achieved by replacing fresh water with process water. Water from different sources and qualities—fresh water, the outflow from an internal ultrafiltration placed in the machine circuit of a paper mill, and water from a membrane bioreactor used to treat the final effluent of this paper mill—were used to prepare a dual retention system consisting of a cationic polyacrylamide and bentonite. While the behavior of bentonite was not significantly affected by the quality of the water used in its preparation, the efficiency of the cationic polyacrylamide was reduced to about 12% when it was prepared with water with high anionic trash content and conductivity as a result of a partial neutralization of the charged groups. The effect of nonionic chemical oxygen demand on the efficiency of the polymer was negligible. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9010029

The role of iron on the degradation and mineralization of organic compounds using conventional Fenton and photo-Fenton processes / Daphne Hermosilla in Chemical engineering journal, Vol. 155 N° 3 (Decembre 2009) 

Public ISBD [article]  in Chemical engineering journal > Vol. 155 N° 3 (Decembre 2009) . - pp. 637-646 Titre : The role of iron on the degradation and mineralization of organic compounds using conventional Fenton and photo-Fenton processes Type de document : texte imprimé Auteurs : Daphne Hermosilla, Auteur ; Manuel Cortijo, Auteur ; C.P. Huang, Auteur Année de publication : 2010 Article en page(s) : pp. 637-646 Note générale : Génie Chimique Langues : Anglais (eng) Mots-clés : Fenton  Photo-Fenton  Iron  complex  Phenol  Nitrophenol  Acetic  acid  Oxalic  acid  EDTA  Advanced  oxidation  processes Index. décimale : 660 Résumé : The role of iron on the degradation of different organic compounds, differing in their structure (aliphatic versus aromatic) and iron complex formation capacity, by conventional and photo-Fenton processes was investigated. Results show that these chemical characteristics can affect the degree of treatment in terms of COD and TOC removals. While aromatics exhibited a fast and great reduction in the COD by the conventional Fenton process, aliphatic compounds, apart from acetic acid, required the presence of UV light to enhance treatment results. EDTA and oxalic acid responded very positively to UV irradiation in both COD removal and mineralization, reaching the highest values showed by aromatics; and results depended on the intensity of the UV light applied. Phenol and 4-nitrophenol responded favourably to UV irradiation in terms of mineralization and slightly in COD removal. Reductions in the COD were almost total (95.99%), while only an 80% of reduction in the TOC was achieved, for the best photo-Fenton treatment of oxalic acid, phenol and nitrophenol. 60% COD and 40% TOC removals were achieved correspondingly in the case of EDTA. Acetic acid showed almost no mineralization and low COD removal (≈20%) when treated by a conventional Fenton process; and did not enhanced results when assisting the treatment with UV light. Photo-regeneration of ferrous ion and photo-decarboxylation of iron carboxylates are assessed in the framework of these results. DEWEY : 660 ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6TFJ-4X49YKT-3&_user=6 [...] [article] The role of iron on the degradation and mineralization of organic compounds using conventional Fenton and photo-Fenton processes [texte imprimé] / Daphne Hermosilla, Auteur ; Manuel Cortijo, Auteur ; C.P. Huang, Auteur . - 2010 . - pp. 637-646. Génie Chimique Langues : Anglais (eng) in Chemical engineering journal > Vol. 155 N° 3 (Decembre 2009) . - pp. 637-646 Mots-clés : Fenton  Photo-Fenton  Iron  complex  Phenol  Nitrophenol  Acetic  acid  Oxalic  acid  EDTA  Advanced  oxidation  processes Index. décimale : 660 Résumé : The role of iron on the degradation of different organic compounds, differing in their structure (aliphatic versus aromatic) and iron complex formation capacity, by conventional and photo-Fenton processes was investigated. Results show that these chemical characteristics can affect the degree of treatment in terms of COD and TOC removals. While aromatics exhibited a fast and great reduction in the COD by the conventional Fenton process, aliphatic compounds, apart from acetic acid, required the presence of UV light to enhance treatment results. EDTA and oxalic acid responded very positively to UV irradiation in both COD removal and mineralization, reaching the highest values showed by aromatics; and results depended on the intensity of the UV light applied. Phenol and 4-nitrophenol responded favourably to UV irradiation in terms of mineralization and slightly in COD removal. Reductions in the COD were almost total (95.99%), while only an 80% of reduction in the TOC was achieved, for the best photo-Fenton treatment of oxalic acid, phenol and nitrophenol. 60% COD and 40% TOC removals were achieved correspondingly in the case of EDTA. Acetic acid showed almost no mineralization and low COD removal (≈20%) when treated by a conventional Fenton process; and did not enhanced results when assisting the treatment with UV light. Photo-regeneration of ferrous ion and photo-decarboxylation of iron carboxylates are assessed in the framework of these results. DEWEY : 660 ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6TFJ-4X49YKT-3&_user=6 [...]