X-ray absorption and micro X-ray fluorescence spectroscopy investigation of copper and zinc speciation in biosolids

Date

2011

Authors

Donner, Erica
Howard, Daryl
de Jonge, Martin
Paterson, David
Cheah, Michael
Naidu, Ravi
Lombi, Enzo

Journal Title

Journal ISSN

Volume Title

Publisher

American Chemical Society

Abstract

Despite its pivotal role in determining the risks and time frames associated with contaminant release, metal speciation remains a poorly understood aspect of biosolids chemistry. The work reported here used synchrotron-based spectroscopy techniques to investigate the speciation of copper and zinc in a range of Australian biosolids. High resolution element mapping of biosolids samples using micro X-ray fluorescence spectroscopy revealed considerable heterogeneity in key element associations, and a combination of both organic and inorganic copper and zinc binding environments. Linear combination fitting of K-edge X-ray absorption spectra indicated consistent differences in metal speciation between freshly produced and stockpiled biosolids. While sulfide minerals play a dominant role in metal binding in freshly dewatered biosolids, they are of lesser importance in dried biosolids that have been stockpiled. A degree of metal binding with iron oxide minerals was apparent but the results did not support the hypothesis that biosolids metals are chiefly associated with iron minerals. This work has potential implications for the long-term stability of metals in biosolids and their eventual fate following land application.

Description

Keywords

Keywords: Contaminant release; Copper and zinc; Element mapping; High resolution; Iron minerals; Key elements; Land applications; Linear combinations; Long term stability; Metal binding; Metal speciation; Micro X-ray fluorescence spectroscopy; Time frame; X-ray abs

Citation

Source

Environmental Science and Technology

Type

Journal article

Book Title

Entity type

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Restricted until

2037-12-31