A5026766289- Mine drainage and remediation techniques
- Metal Extraction and Bioleaching
- Tailings Management and Properties
- Groundwater and Isotope Geochemistry
- Arsenic contamination and mitigation
- Geochemistry and Geologic Mapping
- Coal and Its By-products
- Mining and Resource Management
- Geochemistry and Elemental Analysis
- Heavy metals in environment
- Silicon Effects in Agriculture
- Geology and Paleoclimatology Research
- Soil and Unsaturated Flow
- Water Quality and Pollution Assessment
- Groundwater flow and contamination studies
- Mining and Gasification Technologies
- Minerals Flotation and Separation Techniques
- Concrete and Cement Materials Research
- Geological formations and processes
- Coastal wetland ecosystem dynamics
- Radioactive element chemistry and processing
- Engineering and Environmental Studies
- Clay minerals and soil interactions
- Mineral Processing and Grinding
- Soil Geostatistics and Mapping
Southern Cross University
2009-2024
Electricity Supply Board (Ireland)
2024
University of Canberra
2019-2024
Federation University
1990-2017
University of South Australia
2013-2015
Monash University
2009-2012
CRC CARE
2011
Lismore Base Hospital
2010
CSIRO Land and Water
2009
Australian Nuclear Science and Technology Organisation
2009
This study describes the sorption of As(V) and As(III) to schwertmannite as a function pH arsenic loading. In general, was greatest at low pH, whereas high favored As(III). The actual equivalent strongly loading dependent, decreasing from ∼ 8.0 loadings <120 mmolAs molFe−1 4.6 380 molFe−1. Sorption isotherms for were characterized by strong partitioning solid-phase capacities 225−330 mmolAs(V) loadings. contrast, revealed weak affinity versus yet greater compared with (when > 4.6). caused...
Abstract The rates of carbon bio‐sequestration within silica phytoliths the leaf litter 10 economically important bamboo species indicates that (a) there is considerable variation in content occluded (PhytOC) leaves between different species, (b) this does not appear to be directly related quantity plant but rather efficiency encapsulation by silica. PhytOC under experimental conditions ranged from 1.6% 4% weight. potential phytolith leaf‐litter component for bamboos up 0.7 tonnes dioxide...
Oxidation of arsenite (As(III)) is a critical yet often weak link in many current technologies for remediating contaminated groundwater. We report novel, efficient oxidation reaction As(III) conversion to As(V) using commercial available peroxymonosulfate (PMS). rapidly oxidized by PMS with utilization efficiency larger than 90%. Increasing concentrations and pH accelerate As(III), independent the availability dissolved oxygen. The addition enables oxidize completely within 24 h, even...
Arsenic and chromium are often abundant constituents of acid mine drainage (AMD) most harmful as arsenite (As(III)) hexavalent (Cr(VI)). To simultaneously change their oxidation state from As(III) to As(V), Cr(VI) Cr(III), is a potentially effective attractive strategy for environmental remediation. The coabundance in natural environments indicates negligible direct interaction. addition H2O2 enables greatly accelerates the simultaneous reduction Cr(VI). These reactions further enhanced at...
The effect of acid-volatile sulfide (AVS) oxidation on Fe−S cycling and water quality in coastal flood plain drains from acid-sulfate soil landscapes was examined using natural sediments synthetic iron monosulfide. Oxidation AVS occurred rapidly (half-time ≤ 1 h) produced elemental sulfur (S80(s)) oxyhydroxide (FeOOH(s)). initial rapid process without significant acidification or changes to the aqueous-phase composition. Severe (pH < 4) only once S80(s) began oxidize SO4 (within 2−3 days...
Iron-monosulfide oxidation and associated S transformations in a natural sediment were examined by combining selective extractions, electron microscopy K-edge X-ray absorption near-edge structure (XANES) spectroscopy. The this study was collected from waterway receiving acid−sulfate soil drainage. It contained high acid-volatile sulfide content (1031 μmol g−1), reflecting an abundance of iron-monosulfide. iron-monosulfide speciation the initial sample dominated nanocrystalline mackinawite...
In acid-mine drainage and acid-sulfate soil environments, the cycling of Fe As are often linked to formation fate schwertmannite (Fe8O8(OH)8−2x(SO4)x). When schwertmannite-rich material is subjected near-neutral Fe(III)-reducing conditions (e.g., in reflooded soils or mining-lake sediments), resulting Fe(II) can catalyze transformation goethite. This work examines effects arsenic(V) arsenic(III) on Fe(II)-catalyzed investigates associated consequences this mineral for arsenic mobilization. A...
SUMMARY A re‐interpretation of published data shows: firstly, that the hydrophobic properties soil organic matter can increase amount air encapsulation within materials during water uptake; and secondly, this increased reduce uptake rates sufficiently to prevent slaking. This aggregate stabilizing mechanism suggests novel approaches management, based on production non‐uniformly distributed intra‐aggregate pores, could be used improve soils whose aggregates fail when wetted rapidly.
Tidal seawater inundation of coastal acid sulfate soils can generate Fe- and SO4-reducing conditions in previously oxic-acidic sediments. This creates potential for mobilization As during the redox transition. We explore consequences by investigating hydrology, porewater geochemistry, solid-phase speciation, mineralogical partitioning across two tidal fringe toposequences. Seawater induced a tidally controlled gradient. Maximum (∼400 μg/L) occurred shallow (<1 m), intertidal, transition zone...
The accumulation and behavior of arsenic at the redox interface Fe-rich sediments is strongly influenced by Fe(III) precipitate mineralogy, As speciation, pH. In this study, we examined Fe during aeration natural groundwater from intertidal fringe a wetland being remediated tidal inundation. was initially rich in Fe2+ (32 mmol L−1) (1.81 μmol with circum-neutral pH (6.05). We explore changes solid/solution partitioning, speciation mineralogy long-term continuous using combination chemical...