Author | dc.contributor.author | González, J. C. | |
Author | dc.contributor.author | García, S. I. | es_CL |
Author | dc.contributor.author | Bellú, Sebastián | es_CL |
Author | dc.contributor.author | Atria Salas, Ana María | es_CL |
Author | dc.contributor.author | Salas Pelegrin, Juan Manuel | es_CL |
Author | dc.contributor.author | Rockenbauer, A. | es_CL |
Author | dc.contributor.author | Korecz, L. | es_CL |
Author | dc.contributor.author | Signorella, Sandra | es_CL |
Author | dc.contributor.author | Sala, Luis F. | es_CL |
Admission date | dc.date.accessioned | 2010-06-01T21:04:22Z | |
Available date | dc.date.available | 2010-06-01T21:04:22Z | |
Publication date | dc.date.issued | 2009-09-02 | |
Cita de ítem | dc.identifier.citation | POLYHEDRON 28(13): 2719-2729 | en_US |
Identifier | dc.identifier.issn | 0277-5387 | |
Identifier | dc.identifier.uri | https://repositorio.uchile.cl/handle/2250/120954 | |
Abstract | dc.description.abstract | Selective oxidation of galacturonic residues of oligo and polyuronic acids by Cr-VI affords CO2/HCO2H, oxidized uronic acid, and Cr-III as final redox products. Kinetic studies show that the redox reaction proceeds through a mechanism combining Cr-VI -> Cr-IV -> Cr-II and Cr-VI -> Cr-IV -> Cr-III pathways. The mechanism is supported by the observation of free radicals, CrO22+ and Cr-V as reaction intermediates. The EPR spectra show that five- and six coordinated oxo-Cr-V intermediates are formed. Penta-coordinated oxo-Cr-V species are present at any [H+], whereas hexa-coordinated ones are only observed at pH <1. At low pH Cr-V predominating species are coordinated by carboxylate groups and O-ring (g(iso) = 1.9783/5). At pH 7.5, the predominating ones are those coordinated by alcoholate groups of the ligand (g(iso) = 1.9800). Polygal can reduce Cr-VI and efficiently trap Cr-III. This behaviour represents an interesting model for the study of biomaterials, which possess a high proportion of polygal, in order to remove chromium from polluted waters. | en_US |
Lenguage | dc.language.iso | en | en_US |
Publisher | dc.publisher | PERGAMON-ELSEVIER SCIENCE LTD | en_US |
Keywords | dc.subject | Chromium | en_US |
Título | dc.title | Oligo and polyuronic acids interactions with hypervalent chromium | en_US |
Document type | dc.type | Artículo de revista | |