Transformations of mercury, iron, and sulfur during the …
Experimental parameters are scaled according to the goethite specific surface area (SSA) (fixed at 90 m 2 g −1), solids concentration (starting at 5 g L −1 and corrected for dilution and sampling), and an assumed reactive surface site density of six sites per nm −2 (Cornell and Schwertmann, 2003).These quantities yield an estimated …
Chapter 6: Weathering and Soil Practice Flashcards | Quizlet
Study with Quizlet and memorize flashcards containing terms like Which of the following is/are most susceptible to chemical weathering by dissolution? A) quartz B) clay minerals C) iron oxides D) calcite, What two factors speed up rates of chemical reaction and weathering in rocks and soils? A) low temperatures; very dry B) low temperatures; very …
Carbon mineralization and geological storage of CO2 in basalt
This rapid dissolution of Mg suggests that altered basalt is a promising feedstock for CO2 mineralization. This study provides theoretical support for developing technologies to utilize altered ...
FRACTIONATION OF IRON AND TITANIUM ISOTOPES BY …
produced low- and high-Ti mare basalt suites. Though ilmenite-bearing lunar magma ocean cumulates have often been invoked as the source of titanium enrichment in the lunar …
Leaching of ilmenite to produce titanium based materials: a …
The maximum dissolution of ilmenite was obtained on agitating ilmenite with HCl at a speed of 400 rpm for 300 min resulting in 96.37% and 92.87%, leaching of iron and titanium, respectively. The rate of dissolution could be controlled by two different mechanisms, mainly solid or product layer diffusion and chemical reaction.
Dissolution of a lunar basalt simulant as affected by pH …
The dissolution of a lunar simulant (MLS-1) basalt was examined at 298 K; pH 3, 5, and 7; and in the presence of citrate and oxalate anions. The basalt was mined from an abandoned quarry in Duluth, Minnesota. The relative abundance of minerals in the basalt are plagioclase > pyroxene > olivine > ilmenite. The chemical composition and …
Iron isotopic and chemical tracing of basalt alteration and …
We found that at thermodynamic equilibrium, oxidized iron would precipitate as jarosite at low pH (2–4) and as Fe (oxyhydr)oxides at higher pH. However, the reaction kinetics of basalt dissolution and Fe(II) aq oxidation favor Fe (oxyhydr)oxides precipitation rather than jarosite precipitation. This is because basalt dissolution would buffer ...
Reactive transport modelling of an intra-basalt sandstone …
Key elements such as aluminium and iron were not present in the initial formation water, and the availability of these was controlled by the dissolution of primary minerals and basalt.
Iron isotope fractionation during leaching of granite and basalt …
Semantic Scholar extracted view of "Iron isotope fractionation during leaching of granite and basalt by hydrochloric and oxalic acids" by J. Chapman et al. ... We studied stable iron isotope fractionation during dissolution of a biotite and chlorite enriched mineral fraction from granite by HCl and 5 mM oxalic acid in a pH range of 4-5.9.
Dissolution of primary minerals of basalt in natural waters: I
The dissolution reactions for primary minerals of basalt in aqueous solution used in the present study are given in Table 1.They have been expressed in terms of those aqueous species that were generally found to be dominant in natural waters in the basaltic terrain of Iceland (see Stefánsson et al., 2000).By expressing the reactions in …
Bioleaching of ilmenite and basalt in the presence of iron …
Reductive dissolution of iron (III) from ilmenite ore (FeTiO3) by iron reducing bacteria. Vol. 2848, Issue., p. 030023. CrossRef; ... Bioleaching of ilmenite and basalt in the presence of iron-oxidizing and iron-scavenging bacteria. Volume 12, Issue 2; Jesica U. Navarrete ...
Carbon mineralization and geological storage of CO2 in basalt
Large igneous provinces consist of giant magmas (iron- and magnesium rich) and include continental flood basalts, volcanic passive margins, and associated intrusive rocks. ... Third, dissolution of the basalt reservoir and precipitation of carbonate minerals can clog the pores, leading to injectivity problems (Hövelmann et al., 2012; Wolff ...
Dissolution and secondary mineral precipitation in basalts …
The reactive mineral surface accessibility and flow intensity would also enhance, and even pos-. sibly control, the leaching rate in rocks when interacting with aqueous carbonic acid. Hydrogen ...
Incongruent dissolution of silicates and its impact on the
The paper analyzes the process of incongruent dissolution of silicates taking place in close proximity to a talc mine. The chemical and phase composition as well as the concentrations and mobility ...
Iron isotope fractionation during leaching of granite and basalt …
However, with basalt, the rate of change of Δ 56 Fe solution–rock early during the dissolution was greater compared to the granite. Although we have no data at 10 h, extrapolation of early and late trends suggests that isotopic values were stable in both hydrochloric and oxalic acid leachate solutions by ∼20 h ( Fig. 4 b), significantly ...
Dissolution and secondary mineral precipitation in basalts …
One of the leading hydrothermal alteration processes in volcanic environments is when rock-forming minerals with high concentrations of iron, magnesium, and calcium react with CO 2 and water to form carbonate minerals. This is used to the advantage of geologic sequestration of anthropogenic CO 2.Here we experimentally …
The geochemical evolution of basalt Enhanced Rock
The dissolution rate, r, of this glass can be estimated taking account of (Oelkers and Gislason, 2001, Gislason and Oelkers, 2003) (3) r = 1 A geo d m basalt dm water dm water dt where A geo corresponds to the total geometric surface area of basalt in the soil column, d m basalt dm water designates the mass of basalt dissolved into each ...
The release of iron-bearing minerals and dissolution of …
Dissolution of aluminosilicates and Fe-oxyhydroxide minerals from granitic eluvium using bacteria of Bacillus genus was monitored with solution chemistry, granulometric and X-ray analyses as well ...
(PDF) Mechanisms of dissolution of iron oxides in aqueous …
The mechanism of dissolution of pure iron oxides by means of organic acids comprises two different chemical pathways: (a) non-reductive dissolution and (b) reductive dissolution. In this paper, the thermodynamic analysis of these pathways for the iron oxides-oxalic acid system is presented. In low acid solutions (pH higher than 3) the only ...
Carbon Fate, Iron Dissolution, and Molecular …
Permafrost soils store ∼50% of terrestrial C, with Yedoma permafrost containing ∼25% of the total C. Permafrost is undergoing degradation due to thawing, with potentially hazardous effects on landscape stability and water resources. Complicating ongoing efforts to project the ultimate fate of deep p …
Rayleigh fractionation of iron isotopes during pedogenesis along …
1. Introduction. The weathering reactions of iron (Fe) intersect with many aspects of the biogeochemical functioning of soils (Crews et al., 1995, Torn et al., 1997, Darke and Walbridge, 2000, Miller et al., 2001, Küsel et al., 2002).Thermodynamic transformation of initially ferrous-bearing primary basalt minerals in oxic environments is …
(PDF) An experimental study of crystalline basalt dissolution from …
(a) The crystalline basalt before dissolution experiments, (b) the basalt after it was dissolved in dissolution experiments at pH 10 at 25, 50, and 75 °C for total of 623 h.
The effect of Fe–Ti oxide separation on iron isotopic
Titanomagnetite (Tmag) is a common Fe–Ti oxide phenocryst phase in evolved basaltic lavas, but the effect of its separation on Fe isotopic evolution of …
Dissolution and secondary mineral precipitation in basalts …
This provides good samples for studying hydrothermal alteration and secondary mineral precipitation by CO 2 -rich water with implications for carbon capture …
Reactivity and Dissolution Characteristics of Naturally …
This study investigates the reactivity and dissolution behaviors of altered basalt during the reaction with CO 2 -rich fluids and compares it with unaltered basalt …
Iron isotope fractionation during proton- and ligand …
We studied stable iron isotope fractionation during dissolution of a biotite and chlorite enriched mineral fraction from granite by HCl and 5 mM oxalic acid in a pH range of 4–5.9.Batch experiments covered a time period from 2 h to 100 days and were performed at initial potassium concentrations of 0, 0.5, and 5 mM to induce different …
(PDF) Dissolution kinetics of iron and aluminium from red …
The mechanism for the dissolution of both iron and aluminium followed first order kinetic model equation (F1), -In (1-α) = kt, controlled by interfacial chemical reaction, with the apparent ...
Dissolution of primary minerals of basalt in natural waters: I
The reduced products, which are rich in titanium oxycarbide, Ti 2 O 3 and iron, were prepared after reacting at 1550 °C for 3 h. The Fe content in the reduced …
Laboratory and field studies of colloidal iron oxide dissolution as
Protozoan-mediated dissolution of the same iron oxide phase proceeds at a rate ranging from 1–6% per day, depending on grazing turnover rates. Thus, while photolysis should dominate the redox cycling of refractory iron solids in near-surface waters under bright daytime conditions, phagotrophy is likely to be a more important process overall ...
Iron isotope fractionation during leaching of granite and basalt …
During the granite experiments, alteration of biotite to chlorite, followed by dissolution of chlorite, were likely the dominant processes, whilst in the basalt experiments, dissolution of ...