Potential of Brass to Remove Inorganic Hg(II) from Aqueous Solution through Amalgamation

Abstract

Brass shavings (CuZn45) were tested for their efficiency to remove Hg(II) from contaminated groundwater through amalgamation. The study was focused on long-term retention efficiency, the understanding of the amalgamation process and kinetics, and influences of filter surface alteration. Column tests were performed with brass filters (thickness 3 to 9 cm) flushed with 1000 μg/L Hg solution for 8 hours under different flow rates (300 to 600 mL/h). Brass filters consistently removed >98% of Hg from solution independent of filter thickness and flow rate. In a long-term experiment (filter thickness 2 cm), Hg retention decreased from 96 to 92% within 2000 hours. Batch and column experiments for studying kinetics of Hg removal indicate ~100% Hg removal from solution within only 2 hours. Solid-phase mercury thermo-desorption analysis revealed that Hg(0) diffusion into the brass surface controls kinetics of mercury retention. Brass surface alteration could be observed, but did not influence Hg retention.

Evaluation of engineered sorbents for the sorption of mercury from contaminated bank soils: a column study

“…Studies have aimed to reduce the bioavailability of Hg for methylation and the bioaccumulation of MeHg (Gilmour et al 2013b ). Sorbents investigated include functionalized mesoporous silica (Fryxell et al 1999 ), organocation-modified clay, brass (Wenke et al 2016 ), and carbon-based materials such as activated carbon and biochar (Gilmour et al 2013b ; Gomez-Eyles et al 2013 ; Liu et al 2016 , 2017 ; Paulson et al 2018 ). Mineral or polymer scaffolds with high surface areas and functionalized with reactive ligands may effectively capture dissolved phase metals from solution (Chen et al 1999 ; Crockett et al 2016 ; Say et al 2008 ).…”