Rare Alkali Metals Research Articles

Identifying the genesis of hydrothermal activities in the Xiangcheng fault belt, southwestern China: Evidence from hydrochemistry and stable isotopes

Regional faults are beneficial structures for the formation of hydrothermal activities and have thus become target areas for geothermal resource utilization. Numerous hydrothermal activities have been reported along the Xiangcheng fault belt, particularly concentrating in the Batang, Xiangcheng and Shangri-La areas. In this study, hydrochemistry and stable isotopes were used to identify the genesis of hydrothermal activities in the Xiangcheng fault belt. The pH values of the geothermal water in these regions gradually decreases in this order, while the total dissolved solids gradually increase. The δD and δ18O values indicate the geothermal waters are mainly originated from snowmelt water and meteoric water. The recharge elevation of geothermal waters in Batang, Xiangcheng, and Shangri-La was 4415–4904 m, 4585–5038 m, and 3673–3969 m, respectively. Most geothermal waters belong to the hydrochemical type HCO3-Na, however some Batang geothermal water is of the SO4·HCO3-Na type, influenced by deep geothermal gas, and some Shangri-La geothermal water is of HCO3-Ca·Na type, influenced by shallow cold water and dissolution of carbonate rocks. Correlations of major ions suggest that HCO3-Na type geothermal waters are determined by the dissolution of paragonite, K-feldspar and albite as well as positive ion exchange. According to Na-K-Mg triangle diagram and mineral saturation indices, the geothermal waters do not reach full equilibrium and are mixed with shallow cold. Geothermometers, including cationic and SiO2, and geochemical thermodynamic calculations indicate that the deep and shallow reservoir temperatures are 200–240 °C and 169–193 °C for the Batang area, 194–201 °C and 119–131 °C for the Xiangcheng area, and 156–178 °C and 100–109 °C for the Shangri-La area. Conceptual models of the genesis of hydrothermal activities in the Batang, Xiangcheng, and Shangri-La areas were constructed, respectively. CaCO3 scaling is dominated in the study area. The hydrothermal activities of Batang and Xiangcheng areas with enriched deep materials and high reservoir temperatures are beneficial for rare-alkali metal (e.g., Li). The findings of this study provide a scientific basis for the development and utilization of geothermal resources in the high-temperature hydrothermal activity areas of western Sichuan.

Boron isotope constraints on the migration and accumulation of rare alkali metals in the geyserite cesium deposits in Southern Tibet

Geothermal waters in the Shiquanhe-Yarlun Zangbo geothermal field of southern Tibet are highly enriched in rare alkali metals (RAMs), which form a globally unique geyserite Cs-deposit. Boron isotopes, together with the geochemistry of a local leucogranite, geothermal springs and geyserite were investigated to constrain the migration and accumulation of RAMs in the geyserite cesium deposit. The δ11B values of −9.7‰ to −8.4‰ in tourmalines from the Himalayan leucogranite have shown typical S-type granites. A mass balance calculation indicates that the magma of the S-type granite contained < 10 % dehydrated fluid, which resulted in an enrichment of RAMs by 4–5 times during the partial melting of crustal materials, compared to that in the UCC. The linear relationships of ΣRAMs vs. B and Na + K vs. soluble Si, indicate that further enrichment of RAMs in the geothermal fluids was promoted by intense water–rock interaction at temperatures of 210 to 250 °C in the geothermal system reservoir. A strong adsorption process controlled the hyper enrichment of RAMs (especially Cs) during silica precipitation from the upwelling geothermal water, with the sharp decreases in temperature and pressure leading to the enrichment of Cs in fresh geyserites. Despite loss of RAMs during dehydration of the geyserite during phase transformation from opal-A, opal-CT, and chalcedony to quartz, freshly deposited geyserites have great potential for exploration of RAMs resources in this area.

Geochemistry and rare-metal potential of coals of the Sakhalin coal basin, Sakhalin island, Russia

The study presents new data on the geochemistry coal deposits of the Cretaceous, Paleogene, and Neogene age in the Sakhalin Basin. A wide range of trace elements were studied in 240 coal samples and 138 coal-bearing rock samples from the main fields of the Basin that are under development and available for study. This study demonstrated that the coals in the Sakhalin Basin are generally characterized by concentrations of most trace elements close to the average estimates for the world coals along with, in addition, a mixed chalcophile-siderophile and lithophile geochemical assemblage typical for the transition areas of the continent-ocean zone. On average for the Basin, the coals are enriched in Sc, V, Co, Br, Sr, and Ba compared to the world average. Ash of coals from the Sakhalin Basin is characterized by the above-Clarke content of rare alkali metals (Li, Rb, Cs), Cr, Ni, Cu, Y, and Zr, in addition to the above elements. HREE, Br, Cu, Ag, Hg, Nb, Ge, Mo, W, As, Ni, and Pb specialization was identified for some coalfields. The levels of accumulation of Sc, Y, Sr and heavy lanthanides in coal ash in some coalfields exceed the minimum possible commercial concentrations.The study demonstrated that the geochemical trace element characteristics of coal-bearing sediments in the Sakhalin Basin reflects the peculiarities of the geological evolution of this crustal block. Despite the high tectonic activity and volcanism in the Cenozoic, the specific composition of the rocks in the flanks and the basement of the coal-bearing depressions defined the low rare-metal potential of the basin. Scandium, V, Co, Ni, Ba, and Sr anomalies are associated with the predominantly basic composition of the flanks of the depressions, while local Hg, Sb, W, Cu, and Ge anomalies are connected to the hydrothermal activity.

The genesis of Rare-alkali metal enrichment in the geothermal anomalies controlled by faults and magma along the northern Yadong-Gulu rift

Geothermal water from the hot springs in the Yadong-Gulu rift (YGR) of southern Tibet is extremely enriched in rare-alkali metal (RAM) elements; however, the mechanism of enrichment has long been debated. Much attention has been given to the deep melting magma of the YGR, but no direct evidence indicates whether and how it is connected to the RAM anomaly of hot springs. Determining the mechanism of RAM enrichment and its variations with the time and space of hot springs will contribute to the exploration of the hydrothermal metallogenic systems. This paper presents numerical hydrothermal numerical circulation models constrained by the geological data and the geophysical structure of the YGR. The results illustrate that the depths of boundary faults control the anomalous temperatures of hot springs. High-temperature springs (such as Yangbajing) could be induced by deep faults extending to the middle crust, whereas magma at a depth greater than 10 km has a limited effect on geothermal anomalies. Secondary faults define the extent of hydrothermal circulation and further determine the distribution of thermal anomalies across the rift. We simulate the enrichment and distribution of RAMs from a deep magma source. The pathways of RAMs from the source are consistent with hydrothermal circulation. RAM concentrations are lower in infiltrating groundwater and higher in ascending hot water. In general, deep faults control the hydrothermal circulation of geothermal groundwater. Deep faults and magma further constrain the distribution of RAM anomalies.

Rare Alkali Metals in the Waters of Lithium-containing Deposits in Eastern Transbaikalia

The results of hydrogeochemical studies on the content of rare alkaline elements in man-made waters of mining facilities at Zavitinskoye, Orlovskoye, and Etykinskoye rare metal deposits of Eastern Transbaikalia are presented. Concentrations of these elements are determined both by the content in the ores and rocks of deposits and by their water-migration properties. It was found that the acidic sub-basement waters of the Orlovskoye and the quarry waters of the Zavitinskoye deposits contain abnormally high concentrations of lithium, up to 3.74 and 3.88 mg / L, respectively. The high content of lithium (Li) in the waters of these deposits was determined relative to the average values for the waters of the hypergenesis zone, as well as the standards of maximum permissible concentrations (MPC) of chemicals for water bodies used for fisheries, drinking water, and other activities.

Research Trends on Separation and Extraction of Rare Alkali Metal from Salt Lake Brine: Rubidium and Cesium

ABSTRACT Rubidium and cesium play increasingly important roles in high-tech fields such as aerospace engineering, arms development, and perovskite solar cell fabrication owing to their unique physical and chemical properties. Noting that abundant reserves of rubidium and cesium are often found in the brine of salt lakes, efficiently separating and extracting these resources is crucial for their industrial application. This paper systematically reviews the primary methods for and latest research on rubidium and cesium separation and extraction from salt lake brine and comprehensively evaluates these methods. It elucidates and provides a brief summary in the future development direction. This report is intended to inform future directions for rubidium and cesium recovery from salt lakes and industrial application.

Specifying recharge zones and mechanisms of the transitional geothermal field through hydrogen and oxygen isotope analyses with consideration of water-rock interaction

Recharge mechanism and water–rock interaction (WRI) along the recharge flows in a transitional geothermal system that characterize the chemical and physical properties of vapor and liquid phases, has not yet been fully understood due to complexities of fluid origin and geologic structure. To clarify the fluid origin and WRI processes in the system, this study applied hydrogen and oxygen isotope, B, Cl, and rare alkali metals analyses by considering fractionation characteristics of 18O in rocks and liquid phases, and correction of δ2H and δ18O values in the steam composition. The investigation were done by using 20 samples collected from liquid-dominated, vapor-dominated, and two-phase wells in one of transitional reservoir fields in West Java, Indonesia. The isotopic fractionation factors calculated from a single-step steam separation clearly divided the samples into four zones: boiling parent fluid, vapor, condensate fluid, and diluted steam-heated fluid. The parent fluid that has initial Cl− concentration of 10,000 mg/kg and low water-rock ratio of W/R ≤ 0.2 compositions was found to be the most essential part of the recharge system. Recharge mechanism involves meteoric water from the elevation of 1200 m – 1300 m a.s.l. infiltrates deeply through NE-SW regional faults, and becomes the parent fluid in the reservoir. The residual fluid after boiling of the parent fluid remains in the liquid reservoir with W/R ≤ 0.2, while the vapor phase forms a parasitic steam cap above the liquid reservoir with 0.2 ≤ W/R ≤ 0.7.

Revisiting Alkali Metals As a Tool to Characterize Patterns of Mosquito Dispersal and Oviposition.

Mark-recapture methods constitute a set of classical ecological tools that are used to collect information on species dispersal and population size. These methods have advanced knowledge in disparate scientific fields, from conservation biology to pest control. Gathering information on the dispersal of mosquito species, such as Aedes aegypti, has become critical since the recognition of their role as vectors of pathogens. Here, we evaluate a method to mark mosquitoes that exploits the rare alkali metals rubidium (Rb) and caesium (Cs), which have been used previously to mark adult insects through feeding. We revised this method by adding Rb and Cs directly to water in which the immature stages of Ae. aegypti were allowed to develop. We then assessed the effect of Rb- and Cs-enriched water on fitness, survival and bioaccumulation in both adult females and their eggs. Results indicated that Cs had adverse effects on Ae. aegypti, even at low concentrations, whereas Rb at low concentrations had no measured effects on exposed individuals and accumulated at detectable levels in adult females. The method described here relies on passive uptake of Rb during immature stages, which has the benefit of avoiding handling or manipulation of the dispersive adults, which enables purer measurement of movement. Moreover, we demonstrated that Rb was transferred efficiently from the marked females to their eggs. To our knowledge, Rb is the only marker used for mosquitoes that has been shown to transfer vertically from females to eggs. The application of Rb rather than more traditional markers may therefore increase the quality (no impact on released individuals) and quantity (both adults and eggs are marked) of data collected during MR studies. The method we propose here can be used in combination with other markers, such as stable isotopes, in order to maximize the information collected during MR experiments.

The origin of rare alkali metals in geothermal fluids of southern Tibet, China: A silicon isotope perspective

Geothermal waters from the Semi, Dagejia and Kawu hot springs in the Shiquanhe-Yarlung Zangbo geothermal field of southern Tibet (China) are highly enriched in rare alkali metals (RAM). However, the enrichment mechanism is still hotly debated. Here, we report the first silicon isotope data of these geothermal waters to unravel the origin of the extreme RAM enrichments. Sinter precipitation in the spring vents and water-rock interaction in the deep reservoir controlled both the silicon budget and silicon isotope fractionation. The rates of water-rock interaction and sinter precipitation in three spring sites decrease in the sequences Semi > Kawu > Dagejia, and Dagejia > Kawu > Semi respectively. Silicon isotope fractionation during sinter precipitation (i.e. Δ30Siprecipitate-solution < −0.1‰) is less than that due to water-rock interaction (i.e. Δ30Sisolution-rocks at least as high as −0.47‰), which makes it possible to use the δ30Si signatures of springs to evaluate the intensity of water-rock interaction. Based on the available evidence, a conceptual model of RAM enrichment is proposed: (i) persistent magmatic activity in southern Tibet provided the initial enrichment of the RAM in host rocks and a heat sources for the deep reservoirs of geothermal systems; (ii) the high Cl− content and long residence time (thousands of years) promote the leaching of RAM from the silicate host rocks.

Geochemistry of lepidolitic granitoids from the Mungutiyn Tsagaan Durulj occurrence (central Mongolia)

We studied the geologic position, geodynamic setting, petrology, and geochemistry of veined lepidolitic granitoids from the Mungutiyn Tsagaan Durulj (MTD) occurrence (central Mongolia), found within the area of Mesozoic intraplate rare-metal magmatism. It has been established that their trace-element enrichment resulted from the intense effect of fluids rich in F, K, Li, Rb, Cs, Sn, Be, and W, which arrived from a deep magma chamber of rare-metal granitic melts, on leucogranites with originally weak rare-metal mineralization. Very high contents of F, rare alkali metals, Sn, Be, and W, characteristic of MTD granitoids, are close only to those in greisens of rare-metal granites and topaz-lepidolite-albitic pegmatites. The difference from the greisens in each case might be due to the features of the original rocks. The difference between the greisenized MTD leucogranites and the topaz-lepidolite-albitic pegmatites is more radical: Along with evident petrographic distinctions, it includes an evolution trend toward the albite norm decrease, not typical of Li–F igneous rocks; rock shearing and gneissosity, which must have contributed to their chemical transformation according to this trend; and stably lower contents of Nb and Ta (trace elements which usually accumulate during crystallization fractionation of F–Li granitic melts and are poorly soluble in magmatic fluids). The greisenized MTD granitoids are not only high-grade rare-metal ores of Li, Rb, F, and Sn but are also regarded as an indicator of a deep concealed pluton of rare-metal granites.

Structural, Thermal and Electrical Property of Polycrystalline LaLiMo&amp;lt;sub&amp;gt;2&amp;lt;/sub&amp;gt;O&amp;lt;sub&amp;gt;8&amp;lt;/sub&amp;gt;

This research article reports electrical characterization of a rare earth molybdate based on combination of rare earth (La+3) and alkali (Li+) metal ions. The experimental observation suggests the negative temperature coefficient of resistance behavior of the material. The material has been prepared by standard solid state reaction method, where the synthesis conditions have been optimized by thermal analysis. A possible mechanism for the formation of the polycrystal-line LaLiMo2O8 is reported. A systematic analysis has been done to determine the crystal structure of the powder material and it was found that the powder material was crystallized to tetragonal unit cell structure. Electrical properties have been studied using a.c. impedance measurement. The temperature variation of electrical conductivity of the material shows typical Arrhenius behavior. The activation energy evaluated from conductivity data works out to be ~0.94 ev.

Stability of phenol-formaldehyde ion-exchange sorbents in aqueous solutions

It is shown that ion-exchange sorbents based on phenol-formaldehyde resins can be used for a long time for isolating and separating rare alkali metals without any significant changes in the ion-exchange selectivity and capacity. When the phenol sorbents were used in alkaline solutions at elevated temperatures, carboxyl groups gradually accumulated in them as a result of the oxidation of methylol groups with oxygen dissolved in the solution. This led to a considerable increase in the ion-exchange capacity of the sorbents and a simultaneous decrease in the selectivity with respect to Cs+-Rb+ and Rb+-K+ ions (it is desirable to avoid the drying of phenol ionites in air by storing them in a swelled state in closed vessels).

Alkaline plumes of continents and oceans

Series of continental and oceanic alkaline associations have been compared. Comparison confirms that alkaline plumes originated from the Earth’s liquid core under the continents and, less often, under the oceans. The spatial distribution of alkaline complexes has been analyzed in terms of the plume magmatism theory. Analysis suggests that the zoning and lateral migration of alkaline magmatic centers in alkaline provinces were determined by the migration of an alkaline plume (multiplume) and its alkaline basaltic, alkaline ultramafic, carbonatitic, kimberlitic, and other derivates. Two components are well pronounced in the chemical history of alkaline plume magmatism. The first is the foidaphile component, which persists in all igneous and metasomatic rocks of various alkaline complexes. It includes elements associated with Na and K: rare alkali metals, alkaline earth metals, radioactive elements, rare earths, and others. They make up the important part of the plume that might have separated from the liquid core. The second component is rock-forming mantle–lithospheric, which formed in the asthenosphere during the mixing of mantle and lithospheric sources while the plume ascended to the Earth’s surface.

Sulfuric acid breakdown of fluorite in the presence of silica

We study the reaction of CaF2 with concentrated sulfuric acid in the presence of silica at 120 and 140°C using fluorite mineral, fluorite concentrate, and mica-fluorite ore samples. When steam is fed to the reaction mixture, fluorosilicic acid is formed and then distilled off, materially influencing the fluoride ion recovery. Addition of quartz makes the reaction to proceed in the kinetic area and increases the fluoride ion recovery, while the presence of mica-bound SiO2 displaces the reaction to the diffusion area and decreases the fluoride ion recovery. We have found that rare alkali metals are concentrated as hexafluorosilicates in the insoluble residue during the sulfuric acid breakdown of fluorite in the presence of SiO2.

Thermodynamic Properties of l-Alanine in (RbCl or CsCl) + Water from 298.15 K to 313.15 K

The enthalpy of mixing for aqueous heavy rare alkali metal chloride (RbCl, CsCl) solutions with aqueous l-alanine solutions, as well as the dilution enthalpies of RbCl, CsCl, and l-alanine solution...

Enthalpic Pair Interaction of Rubidium Chloride with α‐Amino Acid in Water at 298.15 K

AbstractThe mixing enthalpies of aqueous heavy rare alkali metal chloride RbCl solutions with aqueous α‐amino acid (L‐glycine, L‐alanine and α‐aminobutyric acid) solutions, as well as the dilution enthalpies of RbCl and α‐amino acid solutions in pure water had been measured at 298.15 K. The transfer enthalpies of RbCl from pure water to aqueous α‐amino acid solutions could be obtained from these data. The enthalpic pair interaction parameters of RbCl with α‐amino acid in water have been evaluated according to the McMillan‐Mayer theory and discussed in terms of the electrostatic interaction, structure interaction and Savage‐wood group additivity mode.

Cascaded Evolution of Mantle Plumes and Metallogenesis of Core‐ and Mantle‐derived Elements

Abstract Mineral deposits are unevenly distributed in the Earth's crust, which is closely related to the formation and evolution of the Earth. In the early history of the Earth, controlled by the gravitational contraction and thermal expansion, lighter elements, such as radioactive, halogen‐family, rare and rare earth elements and alkali metals, migrated upwards; whereas heavier elements, such as iron‐family and platinum‐family elements, base metals and noble metals, had a tendency of sinking to the Earth's core, so that the elements iron, nickel, gold and silver are mainly concentrated in the Earth's core. However, during the formation of the stratified structure of the Earth, the existence of temperature, pressure and viscosity differences inside and outside the Earth resulted in vertical material movement manifested mainly by cascaded evolution of mantle plumes in the Earth. The stratifications and vertical movement of the Earth were interdependent and constituted the motive force of the mantle‐core movement. The cascaded evolution of mantle plumes opens the passageways for the migration of deep‐seated ore‐forming material, and thus elements such as gold and silver concentrated in the core and on the core‐mantle boundary migrate as the gaseous state together with the hot material flow of mantle plumes against the gravitational force through the passageways to the lithosphere, then migrate as the mixed gas‐liquid state to the near‐surface level and finally are concentrated in favorable structural expansion zones, forming mineral deposits. This is possibly the important metallogenic mechanism for gold, silver, lead, zinc, copper and other many elements. Take for example the NE‐plunging crown of the Fuping mantle‐branch structure, the paper analyzes ductile‐brittle shear zone‐type gold fields (Weijiayu) at the core of the magmatic‐metamorphic complex, principal detachment‐type gold fields (Shangmingyu) and hanging‐wall cover fissure‐vein‐type lead‐zinc polymetallic ore fields (Lianbaling) and further briefly analyzes the source of ore‐forming material and constructs an ore‐forming and ‐controlling model.

Predicting the Liquid-Vapor Critical Point from the Crystal Anharmonicity

A ‘universal’ dependence is predicted of the reduced critical parameters (temperature, density, and pressure) on the crystal anharmonicity. The model, which employs the ‘universal’ zero-temperature equation of state in a version of fluid perturbation theory, is apparently the first to predict correctly the critical temperature and density for both the rare gases and Alkali metals.

Predicting the liquid-vapor critical point from the crystal anharmonicity

A "universal" dependence is predicted of the reduced critical parameters, k(B)T(c) / E0(gamma), V(c) / V0(gamma), and P(c)V(c)/k(B)T(c) = Z(c)(gamma), on the crystal anharmonicity gamma (closely related to the Gruneisen parameter gamma(G)). It is based on a simplified embedded-atom type approach which enables one to utilize the universal zero-temperature equation of state in a version of fluid perturbation theory. This model's critical temperature and density agree with the experimental results for both the heavy rare gases ( gamma approximately 2.85) and heavy alkali metals ( gamma approximately 1.35). Predicted critical parameters for many other liquid metals are consistent with previous estimates, but the model is not applicable when directional bonding is important.

Selectivity of phenol–formaldehyde resins and separation of rare alkali metals

The sorption capacity and selectivity of the chemically stable, macroporous phenol–formaldehyde resins with phenolic ion-exchange groups only, towards alkali metal ions have been studied. The selectivity of these resins towards rubidium and cesium ions were found to be significantly greater than that of the sulfonic, carboxylic, phosphonic, nitrated sulfonic and sulfonic–phenolic ion-exchange resins. The contributions of the ion-exchange and molecular sorption mechanisms to the sorption capacity and the selectivity were determined. The synergetic action of the phenolic active groups on the properties of ion-exchange resins is discussed. The resins with phenolic ion-exchange groups only were found to be very efficient for separation of the rare alkali metal ions.