%0 Journal Article %T Zn Isotope Fractionation during Sorption onto Kaolinite %+ Institut de Physique du Globe de Paris (IPGP (UMR_7154)) %+ Institut de Physique du Globe de Paris (IPGP) %+ Institut de Physique du Globe de Paris (IPGP) %A Guinoiseau, Damien %A Gelabert, Alexandre %A Moureau, Julien %A Louvat, Pascale %A Benedetti, Marc %Z EC2CO FIZCAMO project (CNRS-INSU) CAPES713-2011 %< avec comité de lecture %@ 0013-936X %J Environmental Science and Technology %I American Chemical Society %V 50 %N 4 %P 1844-1852 %8 2016-01-13 %D 2016 %R 10.1021/acs.est.5b05347 %K KeyWords Plus:RAY-ABSORPTION SPECTROSCOPY %K SURFACE COMPLEXATION %K PARTICULATE MATTER %K AQUEOUS-SOLUTIONS %K ZINC ISOTOPES %K HIGHER-PLANTS %K ICP-MS %K ADSORPTION %K COPPER %K CU %Z Sciences of the Universe [physics] %Z Sciences of the Universe [physics]/Earth SciencesJournal articles %X In this study, we quantify zinc isotope fractionation during its sorption onto kaolinite, by performing experiments under various pH, ionic strength, and total Zn concentrations. A systematic enrichment in heavy Zn isotopes on the surface of kaolinite was measured, with Delta Zn-66(adsorbed-solution) ranging from 0.11 parts per thousand at low pH and low ionic strength to 0.49 parts per thousand at high pH and high ionic strength. Both the measured Zn concentration and its isotopic ratio are correctly described using a thermodynamic sorption model that considers two binding sites: external basal surfaces and edge sites. Based on this modeling approach, two distinct Zn isotopic fractionation factors were calculated: Delta Zn-66(adsorbed-solution) = 0.18 +/- 0.06 parts per thousand for ion exchange onto basal sites, and Delta Zn-66(adsorbed-solution) = 0.49 +/- 0.06 parts per thousand for specific complexation onto edge sites. These two distinct factors indicate that Zn isotope fractionation is dominantly controlled by the chemical composition of the solution (pH, ionic strength) %G English %L insu-02872487 %U https://insu.hal.science/insu-02872487 %~ INSU %~ UNIV-PARIS7 %~ AFRIQ %~ CNRS %~ IPGP %~ USPC %~ SORBONNE-UNIVERSITE %~ UNIV-PARIS %~ ALLIANCE-SU