Strontium adsorption and desorption in wetlands: Role of organic matter functional groups and environmental implications

Antoine Boyer; Paris Ning; Doug Killey; Martin Klukas; David Rowan; Andre J Simpson; Elodie Passeport

doi:10.1016/j.watres.2018.01.026

Strontium adsorption and desorption in wetlands: Role of organic matter functional groups and environmental implications

Water Res. 2018 Apr 15:133:27-36. doi: 10.1016/j.watres.2018.01.026. Epub 2018 Jan 11.

Authors

Antoine Boyer¹, Paris Ning², Doug Killey³, Martin Klukas³, David Rowan³, Andre J Simpson², Elodie Passeport⁴

Affiliations

¹ Department of Chemical Engineering and Applied Chemistry, University of Toronto, 200 College Street, Toronto M5S 35E, Canada.
² Environmental NMR Centre, Department of Physical and Environmental Sciences, University of Toronto, 1265 Military Trail, Toronto M1C 1A4, Canada.
³ Canadian Nuclear Laboratories, 286 Plant Rd, Chalk River K0J 1J0, Canada.
⁴ Department of Chemical Engineering and Applied Chemistry, University of Toronto, 200 College Street, Toronto M5S 35E, Canada; Department of Civil Engineering, University of Toronto, 35 St George St., Toronto M5S 1A4, Canada. Electronic address: elodie.passeport@utoronto.ca.

PMID: 29353697
DOI: 10.1016/j.watres.2018.01.026

Abstract

Strontium (Sr) is a chemical element that is often used as a tracer in hydrogeochemical studies, and is ubiquitously distributed as a radioactive contaminant in nuclear sites in the form of strontium-90 (Sr-90). At the interface between groundwater and surface water, wetlands possess unique hydrogeochemical properties whose impact on Sr transport has not been investigated thoroughly. In this study, the adsorption and desorption of Sr was investigated on six natural wetland substrates and two mixes of exogenous media and wetland sediment: winter and summer wetland sediments, decayed cattails, wood, leaf litter, moss, bone charcoal, and clinoptilolite. The composition of the organic matter was characterized using carbon-13, solid phase Nuclear Magnetic Resonance analysis. The range of the substrates' adsorption coefficients obtained could be explained by factors indicative of proteins in the organic matter, which were shown to support strong and poorly reversible Sr adsorption. In contrast, the proportion of carbohydrates and lignin were found to be indicative of lower adsorption coefficients and higher desorption. The implications of these results for Sr pollution remediation in wetlands are discussed.

Keywords: Adsorption; C-13 NMR; Desorption; Soil organic matter; Strontium; Wetland.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Adsorption
Geologic Sediments / chemistry
Strontium / chemistry*
Water Pollutants, Chemical / chemistry*
Wetlands

Substances

Water Pollutants, Chemical
Strontium