The Adsorption and Coprecipitation of Silver On Hydrous Ferric Oxides

1967 ◽  
Author(s):  
W Dyck
Keyword(s):  
Hydrous Ferric Oxides ◽  
Ferric Oxides

scholarly journals Hydrous Ferric Oxides in Sediment Catalyze Formation of Reactive Oxygen Species during Sulfide Oxidation

2016 ◽  
Vol 3 ◽  
Author(s):  
Sarah A. Murphy ◽  
Shengnan Meng ◽  
Benson M. Solomon ◽  
Dewamunnage M. C. Dias ◽  
Timothy J. Shaw ◽  
...  
Keyword(s):  
Reactive Oxygen Species ◽  
Sulfide Oxidation ◽  
Reactive Oxygen ◽  
Oxygen Species ◽  
Hydrous Ferric Oxides ◽  
Ferric Oxides

Surface and Textural Heterogeneity of Fresh Hydrous Ferric Oxides in Water and in the Dry State

1993 ◽  
Vol 159 (1) ◽  
pp. 45-52 ◽  
Author(s):  
J.Y. Bottero ◽  
M. Arnaud ◽  
F. Villiéras ◽  
L.J. Michot ◽  
P. de Donato ◽  
...  
Keyword(s):  
Hydrous Ferric Oxides ◽  
Ferric Oxides

Rare earth element partitioning between hydrous ferric oxides and acid mine water during iron oxidation

2004 ◽  
Vol 19 (8) ◽  
pp. 1339-1354 ◽  
Author(s):  
Philip L. Verplanck ◽  
D.Kirk Nordstrom ◽  
Howard E. Taylor ◽  
Briant A. Kimball
Keyword(s):  
Rare Earth ◽  
Rare Earth Element ◽  
Mine Water ◽  
Earth Element ◽  
Iron Oxidation ◽  
Acid Mine Water ◽  
Acid Mine ◽  
Element Partitioning ◽  
Hydrous Ferric Oxides ◽  
Ferric Oxides

scholarly journals Arsenian Pyrite and Cinnabar from Active Submarine Nearshore Vents, Paleochori Bay, Milos Island, Greece

Minerals ◽  
2020 ◽  
Vol 11 (1) ◽  
pp. 14
Author(s):  
Panagiotis Voudouris ◽  
Marianna Kati ◽  
Andreas Magganas ◽  
Manuel Keith ◽  
Eugenia Valsami-Jones ◽  
...  
Keyword(s):  
Sulfuric Acid ◽  
Shallow Water ◽  
High Salinity ◽  
Mediterranean Area ◽  
Hydrothermal Activity ◽  
Continental Arc ◽  
Hydrous Ferric Oxides ◽  
Ferric Oxides ◽  
Low Sulfidation ◽  
Hydrothermal Venting

Active, shallow-water (2–10 m below sea level) and low temperature (up to 115 °C) hydrothermal venting at Paleochori Bay, nearshore Milos Island, Greece, discharges CO2 and H2S rich vapors (e.g., low-Cl fluid) and high-salinity liquids, which leads to a diverse assemblage of sulfide and alteration phases in an area of approximately 1 km2. Volcaniclastic detritus recovered from the seafloor is cemented by hydrothermal pyrite and marcasite, while semi-massive to massive pyrite-marcasite constitute mounds and chimney-like edifices. Paragenetic relationships indicate deposition of two distinct mineralogical assemblages related to the venting of high-Cl and low-Cl fluids, respectively: (1) colloform As- and Hg-bearing pyrite (Py I), associated with marcasite, calcite, and apatite, as well as (2) porous and/or massive As-rich pyrite (Py II), associated with barite, alunite/jarosite, and late-stage hydrous ferric oxides. Mercury, in the form of cinnabar, occurs within the As-rich pyrite (Py I) layers, usually forming distinct cinnabar-enriched micro-layers. Arsenic in colloform pyrite I shows a negative correlation with S indicating that As1− dominates in the pyrite structure suggesting formation from a relatively reducing As-rich fluid at conditions similar to low-sulfidation epithermal systems. On the contrary, As3+ dominates in the structure of porous to massive pyrite II suggesting deposition from a sulfate-dominated fluid with lower pH and higher fO2. Bulk sulfide data of pyrite-bearing hydrothermal precipitates also show elevated As (up to 2587 ppm) together with various epithermal-type elements, such as Sb (up to 274 ppm), Tl (up to 513 ppm), and Hg (up to 34 ppm) suggesting an epithermal nature for the hydrothermal activity at Paleochori Bay. Textural relationships indicate a contemporaneous deposition of As and Hg, which is suggested to be the result of venting from both high-salinity, liquid-dominated, as well as CO2- and H2S-rich vapor-dominated fluids that formed during fluid boiling. The CO2- and H2S-rich vapor that physically separated during fluid boiling from the high-salinity liquid led to calcite formation upon condensation in seawater together with the precipitation of As- and Hg-bearing pyrite I. This also led to the formation of sulfuric acid, thereby causing leaching and dissolution of primary iron-rich minerals in the volcaniclastic sediments, finally resulting in pyrite II precipitation in association with alunite/jarosite. The Paleochori vents contain the first documented occurrence of cinnabar on the seafloor in the Mediterranean area and provide an important link between offshore hydrothermal activity and the onshore mercury and arsenic mineralizing system on Milos Island. The results of this study therefore demonstrate that metal and metalloid precipitation in shallow-water continental arc environments is controlled by epithermal processes known from their subaerial analogues.

Relationship of copper with hydrous ferric oxides: Salobo, Carajás, PA, Brazil

1991 ◽  
Vol 6 (2-3) ◽  
pp. 245-255 ◽  
Author(s):  
Marcello M. Veiga ◽  
Hans D. Schorscher ◽  
William S. Fyfe
Keyword(s):  
Hydrous Ferric Oxides ◽  
Ferric Oxides ◽  
Relationship Of

Study on the effects of soluble microbial product on phosphate adsorption onto fresh hydrous ferric oxides by surface complexation models

2016 ◽  
Vol 74 (10) ◽  
pp. 2446-2453 ◽  
Author(s):  
Yanpeng Mao ◽  
Wenlong Wang ◽  
Chunyuan Ma
Keyword(s):  
Equilibrium Constants ◽  
Surface Complexation ◽  
Phosphate Adsorption ◽  
Stable Operation ◽  
Microbial Product ◽  
Music Model ◽  
Soluble Microbial Product ◽  
Hydrous Ferric Oxides ◽  
Ferric Oxides ◽  
Complexation Reactions

As one of the major soluble organic compounds in membrane bioreactors, soluble microbial product (SMP) can combine the surface sites on hydrous ferric oxides (HFO), which can compete with HFO for the uptake of phosphate. In this study, SMP was extracted from an MBR plant with long-term stable operation, and the effects of SMP on phosphate adsorption onto fresh HFO (FHFO) were investigated at pH values of 6.0 and 7.8 in a two-phase system composed of FHFO (solid phase) and SMP/phosphate (liquid phase). The phosphate adsorption capacity of FHFO was found to decrease significantly with increase in the pH value and SMP concentration. A diffuse layer model (DLM) and a charge distribution multisite complexation (CD-MUSIC) model, which take these factors into account, were developed to describe the speciation of SMP and phosphate on FHFO surface. Both of the models provided good description of phosphate adsorption behavior in the presence of SMP at different pH. The equilibrium constants of surface complexation reactions between SMP and HFO were obtained by inversion calculation as log10K = 15.1 ± 0.11 in DLM model and log10K = 12.1 ± 0.5 in CD-MUSIC model, which can improve the equilibrium constants database of surface complexation models.

scholarly journals Characterisation of hydrous ferric oxides derived from iron-rich groundwaters and their contribution to the suspended sediment of streams

2013 ◽  
Vol 39 ◽  
pp. 59-68 ◽  
Author(s):  
Stijn Baken ◽  
Carin Sjöstedt ◽  
Jon Petter Gustafsson ◽  
Piet Seuntjens ◽  
Nele Desmet ◽  
...  
Keyword(s):  
Suspended Sediment ◽  
Hydrous Ferric Oxides ◽  
Ferric Oxides
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