Formation and stability of Pb-, Zn- Cu-PO4 phases at low temperatures: Implications for heavy metal fixation in polar environments

Low temperatures and frequent soil freezeethaw in polar environments present challenges for the immobilisation of metals. To address these challenges we investigated the chemical forms of Pb, Zn and Cu in an Antarctic land�ll, examined in vitro reaction kinetics of these metals and orthophosphate...

Full description

Bibliographic Details
Published in:Environmental Pollution
Main Authors: White, Duanne, Hafsteinsdóttir, Erla, Gore, Damian, Thorogood, Gordon, Stark, Scott
Format: Article in Journal/Newspaper
Language:English
Published: 2011
Subjects:
Online Access:https://researchprofiles.canberra.edu.au/en/publications/748bc5c3-dbe5-4d49-a0f4-51ca41996b8a
https://doi.org/10.1016/j.envpol.2011.09.035
https://researchsystem.canberra.edu.au/ws/files/9370449/1_s2.0_S0269749111005616_main.pdf
Description
Summary:Low temperatures and frequent soil freezeethaw in polar environments present challenges for the immobilisation of metals. To address these challenges we investigated the chemical forms of Pb, Zn and Cu in an Antarctic land�ll, examined in vitro reaction kinetics of these metals and orthophosphate at 2 and 22 C for up to 185 days, and subjected the products to freezeethaw. Reaction products at both temperatures were similar, but the rate of production varied, with Cu-PO4 phases forming faster, and the Zn- and Pb-PO4 phases slower at 2 C. All metal-orthophosphate phases produced were stable during a 2.5 h freezeethaw cycle to �30 C. Metal immobilisation using orthophosphate can be successful in polar regions, but treatments will need to consider differing mineral stabilities and reaction rates at low temperatures.