X-ray accelerated photo-oxidation of As(III) in solution.
We performed near edge X-ray absorption spectroscopy (XANES) measurements on the arsenic K-edge of As(III) in solution under acidic and basic conditions, after exposure of the solutions to air. Spectra were recorded for increasing exposure times to the X-rays used to perform absorption spectroscopy measurements. We did not find changes for the solution under acidic conditions, whereas we observed significant changes in the case of solution under alkaline conditions. To interpret these changes, we compared the obtained spectra with XANES spectra of As(III) and As(V) solutions under alkaline conditions, not exposed to air, and used as standards. Principal component fits using these standards indicate an accelerated conversion of As(III) to As(V) due to the exposure to X-rays.
†Departamento de Fisica Aplicada, Cinvestav-Merida, Merida, Yucatán 97310, Mexico.
Jesus
J
Canche-Tello
†Departamento de Fisica Aplicada, Cinvestav-Merida, Merida, Yucatán 97310, Mexico.
M Cristina
MC
Vargas
‡Instituto de Ciencias Físicas, Universidad Nacional Autónoma de México, A.P. 48-3, Cuernavaca, Morelos 62251, México.
Jorge
J
Hérnandez-Cobos
‡Instituto de Ciencias Físicas, Universidad Nacional Autónoma de México, A.P. 48-3, Cuernavaca, Morelos 62251, México.
Iván
I
Ortega-Blake
§Université Nice Sophia Antipolis, Nice Chemistry Institute, UMR 7272, Parc Valrose, 06100 Nice, France.
Amelie
A
Leclercq
∥Mars Beamline, Synchrotron SOLEIL, 91192 Gif-sur-Yvette Cedex, France.
Pierre Lorenzo
PL
Solari
⊥Earth System Science Department, Stanford University, Stanford, California 94305, United States.
Juan
J
Lezama-Pacheco
§Université Nice Sophia Antipolis, Nice Chemistry Institute, UMR 7272, Parc Valrose, 06100 Nice, France.
Christophe
C
Den Auwer
†Departamento de Fisica Aplicada, Cinvestav-Merida, Merida, Yucatán 97310, Mexico.
José Mustre
JM
de Leon
D018053:Arsenites / Q000737:chemistry*; D010084:Oxidation-Reduction / Q000528:radiation effects; D055668:Photochemical Processes; D012996:Solutions; D056928:X-Ray Absorption Spectroscopy; D014965:X-Rays
D018053:Arsenites; D012996:Solutions; C015001:arsenite