Natural Brines Research Articles

Positive Zeta Potential in Sandstones Saturated With Natural Saline Brine

AbstractIt is widely accepted that the zeta potential in natural sandstones is negative in the brine pH and compositions found in the subsurface. The zeta potential is a measure of the electrical potential at a mineral surface. We report new measurements of the zeta potential using a saline natural brine rich in divalent ions. The sandstone samples were quartz dominated but some also contained dolomite, siderite, and clay minerals. The quartz‐dominated sandstones showed behavior consistent with earlier studies, but the dolomite‐ and siderite‐bearing samples returned positive zeta potentials. We suggest that this is caused by a positive zeta potential on dolomite and siderite mineral surfaces, adsorption of divalent ions onto quartz mineral surfaces, and/or ion exchange with clay minerals. The results have broad implications for the zeta potential of natural sandstones, because the magnitude and polarity of the zeta potential impact geophysical monitoring and the transport of the charged contaminants.

Физическое состояние агрочернозема при использовании природной соли с гербицидной активностью на яровой пшенице

The studies were carried out in order to assess the effect of a 30 % solution of natural salt with herbicidal activity on the physical state of agrochernozem during the cultivation of spring wheat. In a field experiment in the conditions of the Krasnoyarsk forest-steppe, crude natural brines of the Troitsk deposit of the Krasnoyarsk Territory were used, containing in their composition, g/l: sodium – 77,07; magnesium – 0,49; iron – 3,68; calcium – 2,56; potassium – 2,36; chlorides – 131,00; sulfates – 1,51. The concentration of natural salt was obtained by diluting the original base brine. Studies have established that sodium chloride, being the main component of the brines of the Troitskoye deposit, has a migration ability in the "plant-soil" system. A single use of natural salt as a herbicide on spring wheat crops determined a significant transformation of the physical parameters of agrochernozem. It manifested itself in poor reserves of productive moisture, their decrease by 9-12 mm (НСР05 = 3,5) during the period of active growth of spring wheat and an increase in the seasonal variability of the indicator to 46-52 %. Studies have established an increase in the density of the addition of agrochernozem on average for the growing season by 0,07-0,09 g/cm3 while maintaining the loose addition of the arable layer (0,77-0,79 g/cm3). An increase in the content of agronomically valuable fractions 10-0,25 mm in size by 10-12% with the formation of an excellent structural state (74-76 %) of the arable layer is accompanied by intensive destruction of blocky structural units> 10 mm and a significant increase in structural units 5-3 in size; 3-2 m 2-1 mm, which is a consequence of peptization of soil colloids. Keywords: NATURAL BRINE, TROITSKOE DEPOSIT, HERBICIDE, AGROCHERNOZEM, PRODUCTIVE MOISTURE RESERVES, DENSITY OF COMPOSITION, STRUCTURAL COMPOSITION

Novel eugenol-based allyl-terminated precursors and their bio-based polymer networks through thiol-ene click reaction

The design of biobased allyl-terminated precursors with high renewable carbon content for the construction of the thiol-ene polymer networks is essential for sustainable development and green society. In this work, a series of allyl-terminated precursors were synthesized from renewable eugenol and aliphatic diols through a two-step procedure. Then, the alternating aliphatic-aromatic thiol-ene polymer networks with tunable flexibility, thermal and mechanical properties were constructed via solvent-free thiol-ene click photopolymerization. The results showed that the thermal-physical and mechanical properties of the resulting polymers improved with the decrease of the carbon length of the aliphatic diols and the increase of thiol functionality. The thiol-ene polymers exhibited high tensile strength of 22.12 MPa and elongation at break of 126 %. All the polymer networks are thermally stable without obvious weight loss (T5%) up to 270 °C. All the polymers exhibited excellent solvent resistance in alkaline solution, acid solution natural solution brine, water and ethanol solvent. This work successfully provided a facile and simple method to develop biobased ally compounds from eugenol and high-performance polymer networks with tunable performance.

Atomistic Insight into the Behavior of Ions at an Oil-Bearing Hydrated Calcite Surface: Implication to Ion-Engineered Waterflooding

This research provides an atomistic picture of the role of ions in modulating the microstructural features of an oil-contaminated calcite surface. This is of crucial importance for the rational design of ion-engineered waterflooding, a promising technique for enhancing oil recovery from carbonate reservoirs. Inspired by a conventional lab-scale procedure, an integrated series of molecular dynamics (MD) simulations were carried out to resolve the relative contribution of the major ionic constituent of natural brines (i.e., Na+, Cl–, Mg2+, Ca2+, and SO42–) when soaking an oil-bearing calcite surface in different electrolyte solutions of same salinity, namely, CaCl2, MgCl2, Na2SO4, MgSO4, and deionized water (DW). In all cases, we observed the gradual detachment of polar oil molecules (mimicked by decanoate) already paired to Na+ cations, covering the calcite substrate in such a way that carboxylate groups were in contact with the treating solution. The appearance of such a negatively charged interface in conjunction with the bare calcite/brine surface is a likely nanometric source for the disparity of surface characteristics of oil-bearing rocks reported in the literature. The MD results showed the affinity of divalent cations (Ca2+ or Mg2+) for pairing with negatively charged carboxylate functional groups, thereby facilitating desorption of decanoates. Having a compact solvation shell, Mg2+ was not as effective as Ca2+ cations; however, its performance was enhanced in the presence of sulfate anions. We further figured out the tendency of SO42– anions to shielding Na+ sites over the calcite surface, thus limiting the chance of readsorption of carboxylate compounds. Consistent with lab experiences, sulfate was found to assist the access of magnesium cations to the calcite surface as well. Altogether, the present results provide us with a molecular-level validation for the well-known multicomponent ion exchange mechanism proposed for the wettability alteration of carbonate rocks through enriching the divalent ionic content of the injection brine solution.

Concurrent magnesium and boron extraction from natural lithium brine and its optimization by response surface methodology

The high demand of lithium for electromobility and energy storage requires an efficient and sustainable optimization of the current extraction from natural lithium brine process. In this context, this study develops a simultaneous Mg2+ and B3+ extraction system, which could be a contribution to the elimination of precipitation stages and the generation of high purity lithium brine. This dual system composed of a dialkylphosphate ionic liquid and a 2-ethylhexanol/kerosene mixture as magnesium and boron extractors, respectively, was optimized by a mathematical and statistical method known as response surface methodology (RSM). The RSM method identified, through a small number of experiments, the interdependencies of the parameters involved in the extraction process, and calculated their optimal values to achieve the maximum extraction efficiency of Mg2+ and B3+. The optimization was performed from two approaches. The first, maximizing the extraction of Mg2+ and B3+, resulted in experimental efficiencies of 99.17% of Mg2+, 99.36% of B3+ and 23.54% of Li+; whereas the second, in which lithium co-extraction was minimized, yielded efficiencies of 83.56% Mg2+, 99.22% B3+ and 3.36% Li+, results that demonstrate the high extraction capacity of the system, as well as proving the validity of the statistical model.

აზამბურის მირაბილიტის საბადოსა და ტბის წყლის გამოკვლევა უწყლო ნატრიუმის სულფატის მიღების მიზნით

Under the influence of environmental conditions, the article examines the change in the physical and chemical properties of the natural brine system containing sodium sulfate, which is located in Georgia, on the territory of the municipality of Sagarejo. To this purpose in November-June 2019-2020 the full chemical compositions of natural brine were studied at one-month intervals. The following ions were studied in brine: SO4 2-, Cl- , HCO3 - , CO3 2-, Na+ , K+ , Ca2+ and Mg2+.. In water samples, conductivity was also measured. The concentrations of the studied ions in the natural brine vary with the season, in particular, all the studied ions begin to decrease in the fall, sharply decrease in the winter, increase in the spring and significantly increase in the summer.

The role of microbial extracellular polymeric substances on formation of sulfate minerals and fibrous Mg-clays

A variety of Mg-, Na- and Ca-sulfates, including gypsum, and Mg-clays precipitate within the microbial mats that developed seasonally in the hypersaline playa lake El Longar (Central Spain). A multidisciplinary study of the microbial mats along a transect of the lake demonstrates that the degree of lithification of the mats increases from the soft and poorly lithified layers lying on the submerged ground to the highly crystalline mats present in the desiccated fringes.The community composition of the mats is diverse, dominated in terms of OTUs by Proteobacteria, Firmicutes and Cyanobacteria. The Proteobacteria include sulfur-cycling microbes, supporting biogeochemical cycling of this element. Cyanobacteria are the dominant EPS producers in microbial mats and Firmicutes and Proteobacteria have both been shown to play a role in EPS turnover.Several ions (e.g., Mg, S, Si, Al, Fe, Ca, Na) are bound to functional groups of EPS. The abundance of sulfate groups and carboxylic acids suggested that the EPS have a strong binding capacity for Mg2+ and Ca2+, which were higher in the submerged microbial mats. Na, Mg, K, Ca, SO42− and Si are more concentrated in the EPS matrices than in the natural brines. The concentration of ions in the EPS is sufficient to precipitate a mixture of minerals through freeze-drying, that is similar to that found in intact mats. In the EPS of the submerged mats precipitate more types of minerals, including sulfates and Mg-clays, than in the EPS of the exposed areas. These results suggest that the mineral nucleation occurred during the degradation of the mats when the EPS was progressively desiccated and likely released high amounts of ions.The present study helps to understand intrasedimentary growth of sulfates and clays in microbial mats. The presence of these mineral assemblage can be related to a potential biosignature of microbial past life on Earth and possibly also on exoplanets, like Mars.

Дегазационное бурение как эффективный способ разгрузки карбонатных коллекторов вмещающих толщ коренных месторождений алмазов

The issues are considered related to gas manifestations during the development of primary diamond deposits in Yakutia — «Internatsionalnaya» and «Udachnaya» pipes, which are the most difficult in terms of gas-dynamic conditions. Gas manifestations at the field are associated to a greater extent with gases dissolved in the natural brines, and to a lesser extent — with free and sorbed gases. Due to the fact that when developing the underground mines, the sources of explosive gases were recorded, to ensure the safe conduct of mining operations it is required to unload the rock mass. Analysis of data obtained at the different stages of construction and operation of the fields identified the source of the recorded gas manifestations: reservoirs and local gas reservoirs filled with gas-saturated brines. It was revealed that the sources of gas release are zones consisting of cavernous and fractured carbonate rocks complicated by fracturess and low-amplitude tectonics. The analysis of the dynamics of changes in the gas-dynamic, hydrogeological and mining-geological conditions of mines allowed to propose a two-stage advanced degassing of the host rocks as a rather effective method of combating gas manifestations. At the first stage, vertical advance wells are drilled for the entire capacity of the production block. At the second stage, 3–7 horizontal and slightly inclined (up to 10°) wells are drilled in front of the borehole of the underground working under construction. Thus, there is an interval unloading of the massif and the involvement of undeveloped natural gas reserves at the first stage. Actual observations of gas inflows in the underground mine workings showed a significant drop in gas production rates. In such a way, at the «Internatsionalnaya» mine the average gas flow rate per well (per year) decreased from 12.67 to 1.06 m3/h, which confirms the success of the selected two-stage degassing.

Characterization of 14-Crown-4 Ethers for the Extraction of Lithium from Natural Brines: Synthesis, Solubility Measurements in Supercritical Carbon Dioxide, and Thermodynamic Modeling

Improving lithium mining methods is key to furthering lithium’s use as an energy metal. Current mining methods from brines are slow and inefficient and have significant environmental impacts, providing an avenue of research toward developing more effective and less environmentally damaging methods. Supercritical fluid extraction has been evaluated in earlier research for the extraction of metals such as uranium, mercury, and several alkali and earth alkaline metals from aqueous solutions but not for lithium. This study documents the synthesis and preliminary testing of two lithium extractants for possible application in a supercritical carbon dioxide fluid extraction process to recover lithium from natural brines. Based on their high solubility in supercritical carbon dioxide and their desirable structural properties, two 14-crown-4 ethers with different functional groups were selected. In this work, solubility measurements and thermodynamic modeling were carried out to characterize their solubility behavior in the range of P = 100–300 bar with T = 60 °C and T = 85 °C. The main conclusion from this work is the experimental observation of sufficiently high solubilities of the synthesized crown ethers in supercritical carbon dioxide. The highest measured solubility of M14C4, the nonfluorinated 14-crown-4 ether, was 0.30 mol/L at 60 °C and 205 bar, and the highest measured solubility of F14C4, the fluorinated 14-crown-4 ether, was 0.27 mol/L at 60 °C and 285 bar. Another major conclusion was the observed higher solubility of M14C4 than F14C4. We also showed that equation of state modeling provides insight into the factors affecting the crown ether solubility in supercritical carbon dioxide.

Detecting anomalous methane in groundwater within hydrocarbon production areas across the United States

Numerous geochemical approaches have been proposed to ascertain if methane concentrations in groundwater, [CH4], are anomalous, i.e., migrated from hydrocarbon production wells, rather than derived from natural sources. We propose a machine-learning model to consider alkalinity, Ca, Mg, Na, Ba, Fe, Mn, Cl, sulfate, TDS, specific conductance, pH, temperature, and turbidity holistically together. The model, an ensemble of sub-models targeting one parameter pair per sub-model, was trained with groundwater chemistry from Pennsylvania (n=19,086) and a set of 16 analyses from putatively contaminated groundwater. For cases where [CH4] ≥ 10 mg/L, salinity- and redox-related parameters sometimes show that CH4 may have moved into the aquifer recently and separately from natural brine migration, i.e., anomalous CH4. We applied the model to validation and hold-out data for Pennsylvania (n=4,786) and groundwater data from three other gas-producing states: New York (n=203), Texas (n=688), and Colorado (n=10,258). The applications show that 1.4%, 1.3%, 0%, and 0.9% of tested samples in these four states, respectively, have high [CH4] and are ≥50% likely to have been impacted by gas migrated from exploited reservoirs. If our approach is indeed successful in flagging anomalous CH4, we conclude that: i) the frequency of anomalous CH4 (# flagged water samples / total samples tested) in the Appalachian Basin is similar in areas where gas wells target unconventional as compared to conventional reservoirs, and ii) the frequency of anomalous CH4 in Pennsylvania is higher than in Texas + Colorado. We cannot, however, exclude the possibility that differences among regions might be affected by differences in data volumes. Machine learning models will become increasingly useful in informing decision-making for shale gas development.

Characterizing Dispersion Effectiveness at Varying Salinities

ABSTRACT Chemical dispersant formulations typically provide maximum oil dispersion in waters between 30–40 ppt (parts per thousand) salt content, which encompasses typical ocean salinity (~34 ppt). As a result, most laboratory studies of oil dispersion effectiveness (DE) are conducted at low to average ocean salinity. Ocean salinity can vary locally from below 20 ppt during ice and snow melt, to extremely high (over 100 ppt) during freeze up periods or within natural brine pools in deeper waters. In this study, the influence of salinity on DE was evaluated using the baffled flask test (BFT) at a dispersant-to-oil ratio (DOR) of 1:25. Benchtop experiments were conducted with Alaskan North Slope (ANS) crude oil in the presence or absence of chemical dispersant at 5 and 25°C and varying salinities (0.2 to 125 ppt). In addition to DE as determined by BFT, oil droplet size distribution (DSD) and fluorescence intensity was measured via a LISST-100X particle size analyzer (Sequoia Scientific, Inc., Bellevue, WA) and ECO fluorometer (Sea Bird - WET Labs, Inc.; Philomath, OR), respectively. Results indicate that in the presence of dispersant, maximum DE occurred at 25ppt, and decreases above and below this salinity. Concentration of small droplets (<10 μm) was twice as high at 35ppt than at the other salinities in the presence of dispersant at 25°C. Treatments without dispersant did not vary significantly as a function of salinity. Flume tank experiments over a range of salinities support the lab scale results of DSD. These results provide a more comprehensive picture pertaining to the influence of salinity on dispersant usage at high salinities.

The paleohydrological implications of aragonite precipitation under contrasting climates in the endorheic Dead Sea and its precursors revealed by experimental investigations

Carbonate minerals are common in both marine and lacustrine records, and are frequently used for paleoenvironmental reconstructions. The sedimentary sequence of the endorheic Dead Sea and its precursors contain aragonite laminae that provide a detailed sedimentary archive of climatic, hydrologic, limnologic and environmental conditions since the Pleistocene. However, the interpretation of these archives requires a detailed understanding of the constraints and mechanisms affecting CaCO3 precipitation, which are still debated. The implications of aragonite precipitation in the Dead Sea and in its late Pleistocene predecessor (Lake Lisan) were investigated in this study by mixing natural and synthetic brines with a synthetic bicarbonate solution that mimics flash-floods composition, with and without the addition of extracellular polymeric substances (EPS). Aragonite precipitation was monitored, and precipitation rates and carbonate yields were calculated and are discussed with respect to modern aquatic environments. The experimental insights on aragonite precipitation are then integrated with microfacies analyses in order to reconstruct and constrain prevailing limnogeological processes and their hydroclimatic drivers under low (interglacial) and high (glacial) lake level stands. Aragonite precipitation took place within days to several weeks after the mixing of the brines with a synthetic bicarbonate solution. Incubation time was proportional to bicarbonate concentration, and precipitation rates were partially influenced by ionic strength. Additionally, extracellular polymeric substances inhibited aragonite precipitation for several months. As for the lake's water budget, our calculations suggest that the precipitation of a typical aragonite lamina (0.5 mm thick) during high lake stand requires unreasonable freshwater inflow from either surface or subsurface sources. This discrepancy can be resolved by considering one or a combination of the following scenarios; (1) discontinuous aragonite deposition over parts of the lake floor; (2) supply of additional carbonate flux (or fluxes) to the lake from aeolian dust and the remobilization and dissolution of dust deposits at the watershed; (3) carbonate production via oxidation of organic carbon by sulfate-reducing bacteria. Altogether, it is suggested that aragonite laminae thickness cannot be directly interpreted for quantitatively reconstructing the hydrological balance for the entire lake, they may still prove valuable for identifying inherent hydroclimatic periodicities at a single site.

Mineral Precipitations and Hydrochemical Evolution of Brines in Graduation Towers

The purpose of this study is to examine hydrochemical changes of saline groundwater and precipitation of mineral phases during evaporative graduation processes. Therefore, concentrated brines and mineral precipitates were sampled at four graduation towers with differing evaporation approaches. Solid phase compositions were qualitatively and quantitatively analysed. Hydrochemistry changes of dissolved ion concentrations during successive evaporation was assessed by comparing natural with concentrated brines. PHREEQC was used to simulate sequence and quantity of mineral precipitates. Finally, a prognosis for expected precipitations of a newly built graduation tower was made using PHREEQC modelling. The identified mineral phases included calcite, aragonite, gypsum and halite in varying proportions. Concentrations of all investigated ions (except bicarbonate) increase, eventually leading to supersaturation and sequential precipitation of evaporite minerals. Modelled saturation indices show that calcite is the first and halite is one of the last precipitating phases at all sites. Further calculated precipitates include the carbonates dolomite, siderite and strontianite; manganese oxide and hematite; and the sulphates baryte, celestine and gypsum which precipitate depending on local hydrogeochemistry and graduation conditions. Calculated precipitation quantities reach a maximum of 48.6 g/L of applied natural brine at an evaporation grade of 90%. After 25 years, the total expected mass of precipitates at the new graduation tower is about 34.4 t for a graduation process up to a salt content of 19%, and about 356 t for a permanent evaporation grade of 90%. • Except for bicarbonate, concentrations of all ions increase to different degrees. • Mineral precipitations are composed of calcite, aragonite, gypsum and halite. • Modelled precipitation sequence: carbonates, sulphates, chlorides. • Modelled precipitation amounts: max. 48.6 g/L for natural brine at 90% evaporation. • 25 y precipitation forecast for new graduation tower: max. 356 t at 90% evaporation.

OBTAINING HIGH QUALITY LITHIUM CARBONATE FROM NATURAL LITHIUM-CONTAINING BRINES

The aim of this work is to develop a new effective technology for producing high-quality lithium carbonate from natural lithium-containing brines. Freshly deposited aluminum hydroxide was used to separate lithium from the trace amounts of sodium and calcium. It was found that the completeness of lithium extraction from brines purified from magnesium depends on the sorbent dosage, phase contact time, mineralization, pH, and brine temperature. To extract lithium from brines with a mineralization of less than 100 g/dm3, it is necessary to introduce 4 mol of aluminum hydroxide per 1 mol of lithium in the brine. For brines with a mineralization greater than 200 g/dm3, the consumption of the sorbent providing the extraction of lithium more than 96% is 2.5 mol of aluminum hydroxide. Desorption of lithium chloride from lithium-aluminum concentrate is carried out by processing 4-5 canopies of concentrate in a Soxlet type apparatus with the same volume of distilled water. The resulting concentrated solution of lithium chloride is purified from calcium impurities in contact with a saturated solution of lithium carbonate. From a heated aqueous solution of lithium chloride purified from calcium impurities, lithium carbonate is precipitated by dosing a stoichiometric amount of a saturated solution of sodium carbonate into it. The precipitate of lithium carbonate is separated from the mother solution, washed with three portions of a saturated solution of lithium carbonate at a ratio of solid to liquid by weight equal to one to five, in order of decreasing the concentration of sodium in each portion of the wash water. The dried product contains at least 99.6% Li2CO3.

Iodidimonas gelatinilytica sp. nov., aerobic iodide-oxidizing bacteria isolated from brine water and surface seawater.

Chemo-organotrophic iodide (I-)-oxidizing bacterial strains Hi-2T and Mie-1 were isolated from iodide-rich natural gas brine water in Chiba and surface seawater in Mie, Japan, respectively. Cells of strains Hi-2T and Mie-1 were aerobic, Gram-negative and rod-shaped (0.3-0.5µm width and 1.2-4.4µm in length). Two isolates grew optimally at 30°C, pH 7.5 and with 3% NaCl (w/v). Iodide oxidation to form molecular iodine (I2) was a biochemically unique trait for strains Hi-2T and Mie-1. The major cellular fatty acids are C18:1ω7c, C16:1ω5c and C18:1 2-OH. A phylogenetic analysis based on the 16S rRNA gene sequence revealed that strains Hi-2T and Mie-1 were located near Iodidimonas muriae C-3T with 99.2% sequence similarity. The calculated digital DNA-DNA hybridization (dDDH) value of 65.7-65.9% between the two isolates and I. muriae C-3T was lower than the threshold of 70%, which was used for prokaryotic species delineation. Strains Hi-2T and Mie-1 differed in the hydrolysis of aesculin, the hydrolysis of gelatin and the major cellular fatty acids composition from I. muriae C-3T. Considering these biochemical properties, the major cellular fatty acids composition and dDDH value, a novel species is proposed for strains Hi-2T (= JCM 17844T = LMG 28661T) and Mie-1 (= JCM 17845 = LMG 28662), to be named Iodidimonas gelatinilytica.

Recovery of lithium from leach solutions of battery waste using direct solvent extraction with TBP and FeCl3

Although societal interest in lithium has grown due to its increased demand for manufacturing of lithium ion batteries (LIBs), recent research studies about LIB recycling with solvent extraction did not focus on Li recovery and Li remained in the raffinate contaminated with impurities. In this research presented direct Li recovery from LIB waste leachate prior to Ni and Co is a novel and promising approach.The applied SX system (tributyl phosphate (TBP) as extractant and iron(III) chloride (FeCl3) as co-extractant in kerosene) is known from Li separation from natural brines. Batch equilibrium experiments at room temperature were conducted with preloaded organic phase (NaCl and FeCl3, TBP (80% (v/v)) and kerosene (20% (v/v)) and synthetic aqueous LIB waste leachate solution (1.3–1.5 g L−1 Al, 14.2–17.8 g L−1 Co, 1.9–2.2 g L−1 Cu, 0.7–0.8 g L−1 Fe, 2.4–2.7 g L−1 Li, 1.9–2.1 g L−1 Mn, 1.8–2.0 g L−1 Ni, E = 603 mV Ag/AgCl). Loading with emphasis on the competitive extraction between Li and H+, substitution of MgCl2 as chloride source and variation of the phase ratios as well as scrubbing and stripping are investigated in this research.Lithium was selectively separated over divalent LIB metals (Mn, Cu, Co, Ni) and Al(III) from a multicomponent mixture, and the extraction ability of the system is H+ > Li+ > > LIB metals. Aiming for maximum Li extraction initial concentration of H+ was chosen to be 0.1 M. Substitution of MgCl2, used in the brine systems, by AlCl3 as chloride source promoted Li extraction (E(Li) = 87.7% for R(O/A) = 1) due to its strong salting out effect. This resulted in enhanced separation factors (β(Ni) = 2825 and β(Co) = 854 for R(O/A) = 1). Loaded organic phase was purified using 1 M LiCl +2 M AlCl3 scrubbing solution prior stripping. Stripping with 6 M HCl in single-stage at R(O/A) = 5 resulted in stripping liquor containing 12.26 g L−1, 0.02 g L−1, 0.04 g L−1, and 0.04 g L−1 of Li, Mn, Co and Cu, respectively.

Investigation of gas solubility and its effects on natural gas reserve and production in tight formations

In this study, the natural gas solubility in brine and its influence on natural gas reserve and production in a tight gas reservoir have been investigated by the integration of laboratory experiments, phase equilibrium calculations, and numerical evaluation. Experimentally, a visualized PVT cell has been used to measure natural gas solubility at various pressures, temperatures, and salinity. Theoretically, the solubilities of natural gas and natural gas components are calculated using the phase equilibrium theory and equation of state (EOS), which are calibrated by the experimental data first. A sensitivity analysis is implemented to investigate the effects of pressure, temperature, and salinity on natural gas solubility. Subsequently, with the assistance of numerical simulation, the influence of the dynamic gas solubility on the natural gas reserve and production is examined in a tight gas reservoir in Middle Permian Shihezi Formation, Ordos Basin, China. The natural gas solubility is found to be 2.91 m3/m3 at initial reservoir conditions, which contributes to an increase of 1.33% in natural gas reserve. For natural gas and formation brine with specific composition, the gas solubility decreases gradually with the reservoir pressure reduction in the production process. The production prediction indicates that the cumulative gas production from tight formation requires calibration if the dynamic gas solubility is considered. In the field-scale simulation, the cumulative gas production after 10 years is 0.52% higher than the case not considering the dynamic natural gas solubility.

Modeling of the Refractive Index for the Systems MX+H2O, M2X+H2O, H3BO3+MX+H2O, and H3BO3+M2X+H2O. M = K+, Na+, or Li+ and X = Cl− or SO42−

The modeling of the refractive index for binary aqueous solutions of boric acid, sodium chloride, potassium chloride, sodium sulfate, lithium sulfate, and potassium sulfate, as well as ternary aqueous solutions of boric acid in the presence of sodium sulfate, lithium sulfate, or potassium chloride, is reported. The refraction index was represented by molar refraction. It was described as the sum of solutes’ partial molar refraction and solvent molar refraction. The solutes’ partial molar refraction was estimated from the molar refraction of the binary solutions. The excess molar refraction for these systems was described with the equation of Wang et al. The polarizability of the solutes present in the studied systems was estimated using the Lorenz–Lorenz relation. The results showed the model is appropriate for describing the systems studied; the interactions of boric acid, sodium, potassium, lithium, chloride, and sulfate ions with water molecules are relevant to explain the molar refraction and refractive index, and those for the binary systems of lithium chloride and sodium chloride are also relevant the ion–ion interactions. The model is robust and presents estimation capabilities within and beyond the concentrations and temperature range studied. Therefore, the outcomes represent valuable information to understand and follow the industrial processing of natural brines.

Osmotic Stress or Ionic Composition: Which Affects the Early Growth of Crop Species More?

Salinization is a key soil degradation process. An estimated 20% of total cultivated lands and 33% of irrigated agricultural lands worldwide are affected by high salinity. Much research has investigated the influence of salt (mainly NaCl) on plants, but very little is known about how this is related to natural salinity and osmotic stress. Therefore, our study was conducted to determine the osmotic and ionic salt stress responses of selected C3 and C4 cultivated plants. We focused on the early growth stages as those critical for plant development. We applied natural brine to simulate natural salinity and to compare its effect to NaCl solution. We assessed traits related to germination ability, seedlings and plantlet morphology, growth indexes, and biomass and water accumulation. Our results demonstrate that the effects of salinity on growth are strongest among plantlets. Salinity most affected water absorption in C3 plants (28% of total traits variation), but plant length in C4 plants (17–27%). Compensatory effect of ions from brine were suggested by the higher model plants’ growth success of ca 5–7% under brine compared to the NaCl condition. However, trait differences indicated that osmotic stress was the main stress factor affecting the studied plants.

Electrochemical extraction of lithium by ion insertion from natural brine using a flow-by reactor: Possibilities and limitations

Experimental results on the sustainable extraction of lithium chloride from natural brine (Salar de Hombre Muerto, Argentina) using a flow-by electrochemical reactor at constant applied current are presented. The maximum applied current, the current efficiency and the lithium recovery per mass of lithium ion insertion material are evaluated and the flow-by vs. flow-through configurations are compared.