Chloride Brine Research Articles

Simultaneous Conductivity and Viscosity Measurements as a Technique To Track Emulsion Inversion by the Phase-Inversion-Temperature Method

Two kinds of transitions can occur when an emulsified water-oil-ethoxylated nonionic surfactant system is cooled under constant stirring. At a water-oil ratio close to unity, a transitional inversion takes place from a water-in-oil (W/O) to an oil-in-water (O/W) morphology according to the so-called phase-inversion-temperature method. At a high water content, a multiple w/O/W emulsion changes to a simple O/W emulsion. The continuous monitoring of both the emulsion conductivity and viscosity allows the identification of several phenomena that take place during the temperature decrease. In all cases, a viscosity maximum is found on each side of the three-phase behavior temperature interval and correlates with the attainment of extremely fine emulsions, where the best compromise between a low-tension and a not-too-unstable emulsion is reached. The studied system contains Polysorbate 85, a light alkane cut oil, and a sodium chloride brine. All transitions are interpreted in the framework of the formulation-composition bidimensional map.

Prediction of Brine Application for Pretreatment and Anti-Icing

Highway anti-icing strives to prevent the ice—pavement bond by pre-application of chemicals. An effective anti-icing program requires prediction and estimation of the amount, type, and timing of chemicals needed for the expected precipitation event while compensating for time and traffic decay of the chemical on the highway surface. Development of a sodium chloride brine anti-icing methodology was accomplished with an extensive study of brine residual decay on four pavement types. In October and November 2002, brine residual was monitored for up to 3 days after initial application on five sections of four-lane divided highways in Ohio. Four evenly spaced test stations within each highway section were monitored for residual as time passed and traffic accumulated. An instrument that dissolves salt and measures conductivity was used to measure available salt residual. Efficacy of the brine to prevent ice—surface bonding was estimated by using freeze—thaw cycles of various brines. After freezing, the bonds were held vertically as temperature was raised. The appearance of liquid below the interface indicated release. Field and laboratory data were correlated to estimate freezing temperatures for various salt residuals as a function of brine dilution represented by precipitation in depth of rainfall. Results support estimation of brine application requirements for three specific pavements based on expected precipitation and the salt residual models developed in the study. A set of graphs is included to implement the algorithm.

Virioplankton community structure along a salinity gradient in a solar saltern.

The virioplankton community structure along a salinity gradient from near seawater (40 per thousand ) to saturated sodium chloride brine (370 per thousand ) in a solar saltern was investigated by pulsed-field gel electrophoresis. Viral populations with genome sizes varying from 10 kb to 533 kb were detected. The viral community structure changed along the salinity gradient. Cluster analysis of the viral genome-banding pattern resulted in two main clusters. The virioplankton diversity within the samples with salinity from 40 per thousand to 150 per thousand was on the same cluster of a cladogram. The other group consisted of virioplankton from samples with salinity above 220 per thousand. The virioplankton diversity in the different samples was calculated using the Shannon index. The diversity index demonstrated an increase in diversity in the samples along the gradient from 40 per thousand to 150 per thousand salinity, followed by a decrease in the diversity index along the rest of the salinity gradient. These results demonstrate how viral diversity changes from habitats that are considered one of the most common (seawater) to habitats that are extreme in salt concentrations (saturated sodium brine). The diversity index was highest in the environments that lie in between the most extreme and the most common.

Spectroscopic determination of hypochlorous acid, in chloride brine solutions, featuring 5 MeV proton beam line experiments

The irradiation effects of 4.9 MeV protons on salt repository related brines are investigated spectrophotometrically. The induced formation of hypochlorous acid is determined up to doses of 11 kGy in 3.7 M MgCl 2·6H 2O and in a multicomponent brine of high concentration: Brine G. The build-up of hypochlorous acid to a steady-state concentration is found to be independent on the chloride concentration. The ultimate objective of this experiment is the estimation of the G value for HOCl in which meaningful predictions of long-term redox conditions in a nuclear repository strongly depend on. This paper describes our first steps towards the determination of HOCl.

Electrodeposition of Sulfur from Sulfide Contaminated Brines

Sulfide ions were oxidized at graphite electrodes from chloride brines directly into elemental sulfur, which was identified using X-ray photoelectron spectroscopy. This oxidation occurs at potentials where the Pourbaix diagrams predict that elemental sulfur is unstable. Hence the stability of the resulting elemental sulfur is attributed to kinetic rather than thermodynamic considerations. At the beginning, the process is controlled by both charge transfer at the interface and mass transfer within the electrolyte. Electrochemical and impedance measurements revealed that the resulting elemental sulfur passivates the electrode surface and gradually decreases the rate of the process. This is exhibited in exponential decay of the current and an increase of the polarization resistance of the interface with time of electrolysis. The latter shows an inflection which suggests a change in the resistivity of the sulfur film on the electrode surface.

Radiolysis and corrosion of238Pu-doped UO2 pellets in chloride brine

Deaerated 5 M NaCl solution is irradiated in the presence of UO2 pellets with α-radiation from238Pu. Experiments are conducted with238Pu doped pellets and others with238Pu dissolved in the brine. The radiolysis products and yields of mobilized U and Pu from the oxidative dissolution of UO2 are determined. Results found for radiolysis products and for the oxidation/dissolution of pellets immersed in Pu containing brine are similar to results for Pu doped pellets, where the radiation chemical processes occur only in the liquid layer of some 10 σm thickness adjacent to the pellet. The yield of radiolysis products is comparable to earlier results, that of mobilized U from the pellets is < 1% of the total amount of oxidized species. Thus, the radiation chemical yield (G-value) for mobilized hexavalent U is < 0.01 ions/100 eV. In spite of the low radiation yield for the corrosion, the rate of UO2dissolution is higher than expected for the concentrations of long-lived oxidizing radiolysis compounds found in the solutions.

Anodic oxidation of sulfide ions from chloride brines

The anodic oxidation of sulfide ions from chloride brines at graphite electrodes is shown to produce elemental sulfur, that was identified using XPS and EDS measurements. The process is controlled by charge transfer at the interface and diffusion of the sulfide ions in the electrolyte. Potentiostatic current transients reveal exponential decay of the current with time accompanied by gradual increase of the polarization resistance of the interface, at a rate which increases with increase of the potential in the noble direction. This behavior is attributed to passivation of the electrode by the elemental sulfur which deposits on its surface.

Electrochemical behaviour of low carbon steel in concentrated carbonate chloride brines

The polarization curves of low carbon steel in deaerated carbonate bicarbonate buffers (pH 10.3) show three distinct regions: (a) an active region characterized by a Tafel slope of 125 ± 5 mV which is independent of the chloride concentration, (b) a gradual active to passive transition, and (c) a broad passive region. The addition of NaCl has a stronger effect on the passive than on the active region. For NaCl concentrations of 0.1 to 2 M, NaCl has only a small promoting effect (a reaction order of 0.1) on the anodic dissolution of the steel in the active region. Measurements of electrochemical impedance under free corrosion conditions confirm the above findings. The results are explained in terms of the more favourable formation of an iron hydroxy-carbonate complex (called green rust carbonate) than the formation of the corresponding green rust chloride complex. Passivity is attributed to the formation of a protective film containing both FeOOH and Fe2O3. It deteriorates with increasing chloride concentration and potential and improves with increase of buffer concentration. Evidence is also presented for metastable pitting, particularly in the presence of the lower chloride concentration, for example, 0.1, 0.2 and 0.5 M NaCl.

The Merksplas-Beerse geothermal well (17W265) and the Dinantian reservoir

The Merksplas-Beerse well (North Belgium) is a low-enthalpy geothermal production well targeting the Dinantian karstic limestones to a total depth of 1761 m. The presence of methane gas in these limestones generated a particular interest in this well. This paper describes the geological profile of this well and the Dinantian reservoir. The Namurian-Visean boundary at 1630 m is determined by the base of the dipmeter draping pattern in the radioactive Chokier shales (base of the Namurian) on top of the karstified Dinantian limestone. The stratigraphic composition of the transitional interval from Dinantian to Silesian correlates closely to the nearby Turnhout well. The two fractured intervals at 1630-1656 and 1739-1747 m respectively were identified in the Dinantian limestones. They are associated with siliciclastic sections in between pure limestones. The reservoir water is a sodium chloride brine of about 74 °C and at a pressure below the hydrostatic. The water is slightly radioactive because of the contact with the Chokier hot shales. A carbon dioxide gas with methane and nitrogen admixture is dissolved in the water. The gas liquid ratio at standard conditions is about one and the bubble point is around 200-400 psi at reservoir temperature. A long duration pumping test shows a high fracture permeability and a productivity index of 5.4 m3/h/bar with a productivity to injectivity ratio of 1.45.

Products formed from alpha radiolysis of chloride brines

Under alpha irradiation, alkaline chloride brines form H2 (G = 1.2), O2 and chlorate proportional to the dose. The concentrations of additionally formed ClO- and ClO-2 reach an equilibrium value which depends on the dose rate and the chloride concentration. The solutions become strongly oxidizing (Eh = 900 mV), their pH decreases. This behaviour can be simulated by means of a kinetic model.

Cooked and brined shrimps packed in a modified atmosphere have a shelf‐life of &gt;7 months at 0 °C, but spoil in 4–6 days at 25 °C

Summary Spoilage and safety of cooked, brined and modified atmosphere packed shrimps were studied at 0, 5, 8, 15 and 25 °C. Shrimps from two sources, cold and warm waters, were brined in a sodium–chloride brine containing benzoic, citric and sorbic acids. Shelf‐life was above 7 months at 0 °C but only 4–6 days at 25 °C. Apparent activation energy for the effect of temperature on shelf‐life was &gt; 100 kJ mol‐1. This pronounced effect of temperature was explained by changes in spoilage microflora at different storage temperatures. Simple and empirical mathematical models for rates of spoilage were developed for the prediction of shelf‐life at different temperatures. To evaluate safety, products were challenged with Listeria monocytogenes and spores of Clostridium botulinum. Above 5 °C growth responses of L. monocytogenes followed the square root model with a Tmin‐value of +0.2 °C. Cl. botulinum produced toxin at the time of spoilage at 25 °C but only in shrimps with &lt; 3% water‐phase salt.

Lithological and hydrogeochemical role of the density convection in sedimentation basins with halogenous formations

This work treats lithofacies and hydrogeochemical features of the Late Paleozoic sedimentation on the eastern Russian Plate and the geochemistry of principal types of brines, which are spatially and genetically related to halogenous formations. It is shown that the density convection of primary magnesian chloride brines, which inflow into underlying Paleozoic and Proterozoic rocks from Permian evaporite paleobasins, plays the principal role in the formation of chlorocalcium brines that are predominant in the sedimentary cover of the Volga-Urals sedimentation basin. The problem of metamorpbization of brines by exchange-adsorption and hydrolytic processes in terrigenous rocks and the problem of metasomatic dolomitization of limestones are discussed.

A Study of the Chemical Interactions Between Brine Solutions and Dolomite

Summary Application of gelled polymer treatments to change the flow characteristics of a reservoir is a viable improved oil recovery technique. Many gel systems are affected by the solution pH in that gel time is pH dependent. The treatment of carbonate reservoir rock is of particular concern because (1) fluid-rock interaction can alter the pH of the injected solution from the design value and (2) dissolution of carbonate can increase the divalent ion concentration, which can also affect gelation behavior. In this study, the interaction between injected potassium chloride brine and dolomite was investigated through displacement experiments in dolomite cores and mathematical modeling based on equilibrium thermodynamics. Parameters varied were pH of the injected solution, flow rate, and the common ion effect through variation of the calcium and magnesium ion concentrations in the injected solution. Core effluent values of pH and concentrations were measured. Experiments at different flow rates established conditions in which equilibrium was achieved in the core. Equilibrium values of pH were almost constant at a value of 10 when the injected pH was varied between 4 and 10. Results indicate that equilibrium conditions exist for most field conditions. A geochemical model was used to predict equilibrium pH and concentrations, as well as the amount of dolomite dissolved. The model accurately predicted effluent pH of experimental displacement data for the conditions wherein equilibrium was achieved. All model parameters were obtained from literature equilibrium data and were not dependent on curve fitting of the experimental data.

Antimony transport in hydrothermal solutions: an EXAFS study of antimony(V) complexation in alkaline sulfide and sulfide–chloride brines at temperatures from 25°C to 300°C at Psat

Existing electrochemical data suggest that under alkaline conditions, Sb(V) sulfide complexes may be stable under conditions as reducing as those found in hydrothermal ore solutions. To assess the nature of Sb(V) complexes in such solutions, X-ray absorption fine structure spectra (EXAFS) of antimony(V) solutions were obtained at temperatures from 25°C to 300°C at pressures corresponding to the liquid–vapour equilibrium curve for H 2O. Three solution compositions were considered: Solution A consisted of 0.1 m Sb+1.15 m Na 2S; solution B had the composition of 0.05 m Sb+0.2 m NaHS+0.06 m NaOH; and solution C consisted of 0.05 m Sb+0.2 m NaHS+0.06 m NaOH+1 m NaCl. At temperatures <150°C, the inner coordination shell of aqueous Sb(V) contains four sulfur atoms corresponding to the Sb(HS) 4 + complex. Above 150°C, SH − ligands are replaced by OH − to form mixed-ligand Sb complexes. Antimony(V) atoms are found in a second coordination shell at temperatures greater than 250°C, indicating the existence of aqueous polyatomic clusters. No antimony(V) chloride complexation was found in the presence of HS −.

Asteroidal water within fluid inclusion-bearing halite in an H5 chondrite, Monahans (1998)

Crystals of halite and sylvite within the Monahans (1998) H5 chondrite contain aqueous fluid inclusions. The fluids are dominantly sodium chloride-potassium chloride brines, but they also contain divalent cations such as iron, magnesium, or calcium. Two possible origins for the brines are indigenous fluids flowing within the asteroid and exogenous fluids delivered into the asteroid surface from a salt-containing icy object.

Direct osmotic concentration of tomato juice in tubular membrane – module configuration. II. The effect of using clarified tomato juice on the process performance

A study was carried out by using a new tubular direct osmosis module, constructed by PCI UK and equipped with a novel AFC99 membrane 400 μm thick, to investigate the effect of clarifying tomato juice on the rate of direct osmotic concentration. Under virtually the same operating conditions five respective clarifications of juice were tried including full, unclarified, tomato juice. The process performance was calculated in terms of permeation flux. In all the experimental runs the osmotic medium was sodium chloride brine (initial concentration approx. 23% NaCl). A remarkable increase of permeation flux (over 100%) was observed shifting from unclarified to the clarified tomato juice. Clarification was carried out by passing the juice through 35 μm mesh and also by using membranes of molecular weight cut-off 200 000, 100 000 and 25 000 Daltons (Da), respectively, in order to obtain the juice ultrafiltrates. It is also worth mentioning that the flux value obtained with 25 000 Daltons (Da) ultrafiltrate appeared to be considerably higher than values reported in experiments carried out by other researchers, where unclarified juice was used, despite the disadvantage of a far thicker membrane being used in the present investigation. This specific finding discloses great potential in using a combined low temperature and pressure ultrafiltration and direct osmosis process to produce tomato concentrates.

Gold solubility in supercritical hydrothermal brines measured in synthetic fluid inclusions

Dissolved gold contents in chloride brines that were experimentally saturated with gold, magnetite, iron sulfides, orthoclase, and muscovite at 550 degrees to 725 degrees C and 100 to 400 megapascals are reported here. Microsamples of the fluid were isolated at the experimental temperature and pressure as fluid inclusions in quartz. Individual fluid inclusions were opened by laser ablation and analyzed by inductively coupled plasma mass spectrometry. The results show that gold solubility as sulfide species in supercritical brines is far higher than previously supposed. Dissolved gases such as molecular hydrogen sulfide that are ineffective metal-complexing agents at low pressures evidently become highly effective at high pressures.

Chromatographic determination of anions in industrial salt and sodium chloride brines used in chlor–alkali industry

An ion chromatographic method using an ion-exchange column for the simultaneous analysis of sulphate and chlorate in industrial salt and sodium chloride brines has been developed. A mixed eluent of 2.0 m M sodium carbonate and 0.75 m M sodium bicarbonate is used. The effects of various parameters have been reported and critically discussed. The results are precise and afford simultaneous determinations of sulphate and chlorate.

The origin and evolution of Canadian Shield brines: evaporation or freezing of seawater? New lithium isotope and geochemical evidence from the Slave craton

New chemical and isotopic data for deep seated calcium chloride brine from the Miramar Con gold mine, Yellowknife N.W.T., strongly suggest that the brine salinity is of marine origin. Diagnostic marine properties include uniformly elevated Br/Cl ratios typical of seawater concentrated beyond halite saturation, and Li/Br ratios (0.0254–0.0325) and δ 6 Li compositions (−32.1 to −36.3‰) similar to seawater (−32.3‰). The mean δ 6 Li for all mine water samples of −35.1‰ may reflect minor uptake of Li by secondary minerals. This interpretation is supported by analyses of altered metabasalt from fault zones which is enriched in Li but depleted in δ 6 Li (−14.7 to −15.6‰) relative to the unaltered metabasalt (−5.4‰). The mechanism responsible for concentrating the hypersaline brine end member is not unequivocal as evidence exists to support both evaporative and cryogenic processes. On the one hand, the Devonian sedimentary record in the Great Slave Lake region, in conjunction with Yellowknife brine isotopic compositions ( δ 2 H and δ 34 S SO 4 ) that are similar to various Devonian fluids, support an evaporative origin. On the other hand, the Na/Cl–Br/Cl relationship in the brine strongly suggests a cryogenic mechanism. Regardless of the concentrative mechanism, the chemical data indicate that the Yellowknife parent brine was concentrated 28- to 30-fold relative to seawater. The extreme depletion of Mg and enrichment of Ca in the brines, accompanied by Sr/Ca ratios similar to that of seawater, are accounted for by dolomitization of an aragonite-rich marine sediment by the brine before infiltration into the crystalline basement rocks. Subsequent alteration of silicate minerals in the shield added additional Ca and Sr to the brine as indicated by their radiogenic 87 Sr/ 86 Sr ratios (up to 0.7147). Based on mineral balance calculations, the major mineral products of the cryogenic and evaporitic concentration and evolution paths are significantly different. The cryogenic evolution results in some 15% mirabilite, 60% hydrohalite, and 18% dolomite whereas the major minerals formed from the evaporitic evolutionary sequence are 36% halite, 8% gypsum, 17% dolomite, and 30% albite. The great similarity between the calcium chloride brine from Yellowknife and other such Canadian Shield brines indicates that they may share a common marine origin.

Firmness and phytochemical losses in pasteurized yellow banana peppers (Capsicum annuum) as affected by calcium chloride and storage.

The effect of calcium chloride brine treatment on firmness and retention of phytochemicals in pastuerized yellow banana peppers was studied. Shear force values declined during processing and storage, but CaCl(2) treatment resulted in greater firmness retention. Processing reduced ascorbic acid content by 63%, and after 124 days, <10% of ascorbic acid remained. Quercetin and luteolin contents declined 45% during processing, but levels stabilized during storage. Capsaicinoid content was stable during processing and storage. CaCl(2) treatment did not affect ascorbic acid, flavonoid, or capsaicinoid retention during pasteurization and storage. Retention of phytochemicals appeared to be related to their solubility and structural properties.