Some Solution Equilibria Involving Calcium Sulfite and Carbonate. II. The Equilibrium between Calcium Sulfate and Calcium Sulfite in Aqueous Solutions.

Rengemo, Torsten; Brune, Ursula; Sillén, Lars Gunnar; Zaar, B.; Diczfalusy, E.

doi:10.3891/acta.chem.scand.12-0873

Cited by 13 publications

(5 citation statements)

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“…Because of solubility equilibrium, the concentration of S(IV) anions was kept at the 5.6 × 10 -4 M level. 30 This literature value was confirmed with the ionic chromatography method in our laboratory. The pH values established in the reacting solutions were 7.3-7.5.…”

Section: Methodssupporting

confidence: 57%

“…To ensure a low but constant concentration of S(IV) in the course of an experiment, a portion of powdered CaSO 3 · 1 / 2 H 2 O (load 13.5 g/dm 3 , main particle size fraction 0.7−4 μm) was added to the liquid (aqueous phase). Because of solubility equilibrium, the concentration of S(IV) anions was kept at the 5.6 × 10 -4 M level . This literature value was confirmed with the ionic chromatography method in our laboratory.…”

Section: Methodsmentioning

confidence: 56%

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Synergy in the Autoxidation of S(IV) Inhibited by Phenolic Compounds

2003

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The effects of phenol (C6H5OH), catechin [C6H4(OH)2], and gallic acid [HOOCC6H2(OH)3] on the kinetics of aqueous SO2 oxidation by molecular oxygen have been investigated for dilute systems, as pertain to the chemistry of troposphere and surface waters. In experiments performed under batch (homogeneous oxidation) or semibatch (heterogeneous oxidation) conditions, we measured the decay of oxygen with a Yellow Spring Instruments probe or the increase in S(VI) concentration with an Orion conductivity cell. All of the studied phenolic compounds caused inhibition of the uncatalyzed autoxidation of S(IV), but the inhibiting effectiveness of phenol was much lower than that of catechin and gallic acid. The dual role of phenol in not only inhibiting but also promoting action was demonstrated in experiments carried out in the presence of Co or Mn catalyst when the synergy effect was evident. Another extraordinary behavior was observed in the case of gallic acid at prolonged experiments leading to oscillations in the rate of S(VI) formation. The results are discussed in terms of a radical chain reaction with termination by a step first order in SO4 •- radicals and in a phenolic compound, with initiation supplemented by a step first order in phenoxyl radicals and in aqueous S(IV) species. From such a model of the inhibited autoxidation of S(IV), we determined the following rate constants for SO4 • scavenging: 4.3 × 109 M-1 s-1 for catechin and 2.6 × 109 M-1 s-1 for gallic acid. The consequences of this inhibition in the environment are discussed.

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Section: Methodssupporting

confidence: 57%

Section: Methodsmentioning

confidence: 56%

Synergy in the Autoxidation of S(IV) Inhibited by Phenolic Compounds

2003

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“…where KSA = 10"4•63 mol2/dm6 at 25 °C (12). This minimum value is approximately half the amount soluble in pure water (11).…”

Section: Solubility Of Calcium Sulfitementioning

confidence: 95%

Mechanism and kinetics of autoxidation of calcium sulfite slurries

Pasiuk-Bronikowska¹,

Bronikowski²,

Ulejczyk³

1992

Environ. Sci. Technol.

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The kinetics of Co-catalyzed autoxidation of calcium sulfite was studied to deepen knowledge of the mechanism of this chain reaction. Laboratory experiments were performed under heterogeneous conditions using two different reactors: a stirred tank with a plane gas-liquid (slurry) interface and an impinger. The reaction course was followed by monitoring the conductivity of the reacting solution and by quenching with iodine solution, respectively. Mechanistic judgments were derived from the influence of sulfite and catalyst concentrations, and the solid CaS03 load on the kinetics of oxygen absorption. Appropriate reaction orders and rate constants were determined. Phenomena related to the solubility product law that imposed autoxidation rate limitations were analyzed. A soluble sulfate was shown to be a dual-action additive markedly accelerating the autoxidation due to increased sulfite and catalyst solubilities. The results are useful for designers of air pollution control processes.

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“…A critical evaluation of the data contained within these literature sources in conjunction with appropriate data drawn from specific aqueous speciation studies, e.g. Frydman et al (1958), Nilsson et al (1958), Rengamo et al (1958), and Rai et al (1991), should permit satisfactory data to be obtained for the thermodynamic properties of hannebachite. An evaluation of information provided on the partial solid solution series between gypsum and CaSO 3 .2H 2 O by Takahashi (1978, 1979) and Takahashi and Setoyama (1982), and the partial solid solution between hannebachite and CaSO 4 .0.5H 2 O by Jones et al (1977a,b) might also allow for the formulation of appropriate solid solution models to predict precipitation behavior in aqueous sulfitesulfate solution mixtures.…”

Section: Thermodynamic Properties Of Sulfate Phasesmentioning

confidence: 99%

“…Most of the earlier literature is summarized by Lutz (1986), and includes notable contributions by Schwartz and Muller-Clemm (1921), Ghurd et al (1935), Gishler and Maass (1935a,b), Otuka (1939a,b), Frydman et al (1958), Nilsson et al (1958), Rengamo et al (1958), Engelhardt (1962), Templeton et al (1963) and Rodin and Margules (1983a,b). A very precise determination of the solubility of CaSO 3 .0.5H 2 O at 25°C was published subsequently by Rai et al (1991).…”

mentioning

confidence: 99%

Injection of CO2 with H2S and SO2 and Subsequent Mineral Trapping in Sandstone-Shale Formation

Xu¹,

Apps²,

Pruess³

et al. 2004

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Abstract. Carbon dioxide (CO 2 ) injection into deep geologic formations can potentially reduce atmospheric emissions of greenhouse gases. Sequestering less-pure CO 2 waste streams (containing H 2 S and/or SO 2 ) would be less expensive or would require less energy than separating CO 2 from flue gas or a coal gasification process. The long-term interaction of these injected acid gases with shale-confining layers of a sandstone injection zone has not been well investigated. We therefore have developed a conceptual model of injection of CO 2 with H 2 S and/or SO 2 into a sandstone-shale sequence, using hydrogeologic properties and mineral compositions commonly encountered in Gulf Coast sediments of the United States. We have performed numerical simulations of a 1-D radial well region considering sandstone alone and a 2-D model using a sandstone-shale sequence under acid-gas injection conditions. Results indicate that shale plays a limited role in mineral alteration and sequestration of gases within a sandstone horizon for short time periods (10,000 years in present simulations). The co-injection of SO 2 results in different pH distribution, mineral alteration patterns, and CO 2 mineral sequestration than the co-injection of H 2 S or injection of CO 2 alone. Simulations generate a zonal distribution of mineral alteration and formation of carbon and sulfur trapping minerals that depends on the pH distribution. The co-injection of SO 2 results in a larger and stronger acidified zone close to the well. Precipitation of carbon trapping minerals occurs within the higher pH regions beyond the acidified zones. In contrast, sulfur trapping minerals are stable at low pH ranges (below 5) within the front of the acidified zone.Corrosion and well abandonment due to the co-injection of SO 2 could be important 1 issues. Significant CO 2 is sequestered in ankerite and dawsonite, and some in siderite.The CO 2 mineral-trapping capability can reach 80 kg per cubic meter of medium. Most sulfur is trapped through alunite precipitation, although some is trapped by anhydrite precipitation and minor amount of pyrite. The addition of the acid gases and induced mineral alteration result in changes in porosity. The limited information currently available on the mineralogy of natural high-pressure acid-gas reservoirs is generally consistent with our simulations.

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Some Solution Equilibria Involving Calcium Sulfite and Carbonate. II. The Equilibrium between Calcium Sulfate and Calcium Sulfite in Aqueous Solutions.

Cited by 13 publications

References 0 publications

Synergy in the Autoxidation of S(IV) Inhibited by Phenolic Compounds

Synergy in the Autoxidation of S(IV) Inhibited by Phenolic Compounds

Mechanism and kinetics of autoxidation of calcium sulfite slurries

Injection of CO2 with H2S and SO2 and Subsequent Mineral Trapping in Sandstone-Shale Formation

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