Show simple item record

resumen

Abstract
The aggregation kinetics of a humic acid (HA) sample as a function of Ca2+ concentration at pH 5, 7 and 9 was investigated. UV–VIS spectroscopy was employed to quantify the progress of the aggregation reaction, and electrophoresis was used to evaluate the zeta potential of the HA molecules. The aggregation rate increases significantly by increasing Ca2+ concentration at all investigated pH, being higher at pH 9 than at pH 5 and 7. An aggregation mechanism [ver mas...]
dc.contributor.authorKloster, Nanci Soledad
dc.contributor.authorBrigante, Maximiliano Eduardo
dc.contributor.authorZanini, Graciela Pilar
dc.contributor.authorAvena, Marcelo Javier
dc.date.accessioned2017-09-21T13:18:30Z
dc.date.available2017-09-21T13:18:30Z
dc.date.issued2013
dc.identifier.issn0927-7757
dc.identifier.otherhttps://doi.org/10.1016/j.colsurfa.2013.03.030
dc.identifier.urihttp://hdl.handle.net/20.500.12123/1281
dc.identifier.urihttp://www.sciencedirect.com/science/article/pii/S0927775713002197
dc.description.abstractThe aggregation kinetics of a humic acid (HA) sample as a function of Ca2+ concentration at pH 5, 7 and 9 was investigated. UV–VIS spectroscopy was employed to quantify the progress of the aggregation reaction, and electrophoresis was used to evaluate the zeta potential of the HA molecules. The aggregation rate increases significantly by increasing Ca2+ concentration at all investigated pH, being higher at pH 9 than at pH 5 and 7. An aggregation mechanism is proposed, which consists of at least two steps: a rapid binding of Ca2+ to humic molecules, followed by a slower process where HA molecules approach each other and become aggregated. This aggregation is possible because Ca2+ binding decreases the zeta potential of HA from −37 mV to −15 mV and because it is able to form bridges between HA molecules. There is no molecular fractionation up to 60% of aggregation. Above this value, HA aggregates become enriched with more aromatic HA molecules. The fast aggregation of HA in the presence of calcium ions implies that aggregates may temporarily trap, protect and transport pollutants in the environment.eng
dc.formatapplication/pdfeng
dc.language.isoeng
dc.rightsinfo:eu-repo/semantics/restrictedAccesseng
dc.sourceColloids and surfaces. A: Physicochemical and engineering aspects 427 : 76-82. (2015).eng
dc.subjectSueloes_AR
dc.subjectSoileng
dc.subjectCalcio
dc.subjectCalciumeng
dc.subjectIones
dc.subjectIonseng
dc.subjectAcido Húmico
dc.subjectHumic Acidseng
dc.subjectFloculación
dc.subjectFlocculationeng
dc.subject.otherCinética
dc.subject.otherAgregación
dc.subject.otherIones de Calcio
dc.subject.otherCoagulation Kineticseng
dc.subject.otherAggregation Mechanismeng
dc.subject.otherCalcium Ionseng
dc.titleAggregation kinetics of humic acids in the presence of calcium ionseng
dc.typeinfo:ar-repo/semantics/artículoes_AR
dc.typeinfo:eu-repo/semantics/articleeng
dc.typeinfo:eu-repo/semantics/publishedVersioneng
dc.description.filFil: Kloster, Nanci Soledad. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Anguil; Argentina
dc.description.filFil: Brigante, Maximiliano Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Bahía Blanca. Instituto de Química del Sur; Argentina
dc.description.filFil: Zanini, Graciela Pilar. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Bahía Blanca. Instituto de Química del Sur; Argentina
dc.description.filFil: Avena, Marcelo Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Bahía Blanca. Instituto de Química del Sur; Argentina
dc.subtypecientifico


Files in this item

Thumbnail

This item appears in the following Collection(s)

common

Show simple item record