Hydrochemical Characteristics and Evolution of Underground Brine in Lop Nur,Northwestern China

Lop Nur is located at the eastmost end of the Tarim Basin in Xinjiang,Northwestern China.This study reviews the hydrochemical characteristics and evolution of underground brine in Lop Nur,based on analytical data from 429 water samples(mainly brine).It is found that in the NE-SW direction,from the periphery to the Luobei sub-depression,while the hydrochemical type varies from the sodium sulfate subtype(S)to the magnesium sulfate subtype(M),the corresponding brine in the phase diagram transfers from the thenardite phase(Then)area,through the bloedite phase(Blo),epsomite phase(Eps),picromerite phase(Picro),finally reaching the sylvite phase(Syl)area.As for the degree of evolution,the sequence is the periphery<Luobei horizontally and the overlying glauberite brine<the underlying clastic brine vertically.It is concluded that the oxygen and hydrogen isotopic compositions of the brine have evidently been affected through the effects of evaporation and altitude,as well as the changes in local water circulation in recent years.Boron and chloride isotopic compositions show that the glauberite brine is formed under more arid conditions than the clastic one.The strontium isotopic composition indicates that the Lop Nur brine primarily originates from surface water;however,deep recharge may also be involved in the evolution of the brine,according to previous noble gas studies.It is confirmed that the brine in Lop Nur has become enriched with potassium prior to halite precipitation over the full course of the salt lake's evolution.Based on chemical compositions of brine from drillhole LDK01 and previous lithological studies,the evolution of the salt lake can be divided into three stages and it is inferred that the brine in Lop Nur may have undergone at least two significant concentration-dilution periods.

Effects of conductive agent type on lithium extraction from salt lake brine with LiFePO_(4) electrodes

Electrochemical lithium extraction from salt lakes is an effective strategy for obtaining lithium at a low cost.Nevertheless,the elevated Mg:Li ratio and the presence of numerous coexisting ions in salt lake brines give rise to challenges,such as prolonged lithium extraction periods,diminished lithium extraction efficiency,and considerable environmental pollution.In this work,Li FePO4(LFP)served as the electrode material for electrochemical lithium extraction.The conductive network in the LFP electrode was optimized by adjusting the type of conductive agent.This approach resulted in high lithium extraction efficiency and extended cycle life.When the single conductive agent of acetylene black(AB)or multiwalled carbon nanotubes(MWCNTs)was replaced with the mixed conductive agent of AB/MWCNTs,the average diffusion coefficient of Li+in the electrode increased from 2.35×10^(-9)or 1.77×10^(-9)to 4.21×10^(-9)cm^(2)·s^(-1).At the current density of 20 mA·g^(-1),the average lithium extraction capacity per gram of LFP electrode increased from 30.36 mg with the single conductive agent(AB)to 35.62 mg with the mixed conductive agent(AB/MWCNTs).When the mixed conductive agent was used,the capacity retention of the electrode after 30 cycles reached 82.9%,which was considerably higher than the capacity retention of 65.8%obtained when the single AB was utilized.Meanwhile,the electrode with mixed conductive agent of AB/MWCNTs provided good cycling performance.When the conductive agent content decreased or the loading capacity increased,the electrode containing the mixed conductive agent continued to show excellent electrochemical performance.Furthermore,a self-designed,highly efficient,continuous lithium extraction device was constructed.The electrode utilizing the AB/MWCNT mixed conductive agent maintained excellent adsorption capacity and cycling performance in this device.This work provides a new perspective for the electrochemical extraction of lithium using LFP electrodes.

Construction of truncated-octahedral LiMn2O4 for battery-like electrochemical lithium recovery from brine

The extraction of lithium from salt lakes or seawater has attracted worldwide attention because of the explosive growth of global demand for lithium products. The LiMn_(2)O_(4)-based electrochemical lithium recovery system is one of the strongest candidates for commercial application due to its high inserted capacity and low energy consumption. However, the surface orientation of LiMn_(2)O_(4)that facilitates Li diffusion happens to be prone to manganese dissolution making it a great challenge to obtain high lithium inserted capacity and long life simultaneously. Herein, we address this problem by designing a truncated octahedral LiMn_(2)O_(4)(Tr-oh LMO) in which the dominant(111) facets minimize Mn dissolution while a small portion of(100) facets facilitate the Li diffusion. Thus, this Tr-oh LMO-based electrochemical lithium recovery system shows excellent Li recovery performance with high inserted capacity(20.25 mg g^(-1)per cycle) in simulated brine. In addition, the dissolution rate of manganese per 30 cycles is only 0.44% and the capacity maintained 85% of the initial after 30 cycles. These promising findings accelerate the practical application of LiMn_(2)O_(4)in electrochemical lithium recovery.

Construction of porous disc-like lithium manganate for rapid and selective electrochemical lithium extraction from brine

In order to satisfy the growing global demand for lithium, selective extraction of lithium from brine has attracted extensive attention. LiMn_(2)O_(4)-based electrochemical lithium recovery system is one of the best choices for commercial applications because of its high selectivity and low energy consumption.However, the low ion diffusion coefficient of lithium manganate limits the further development of electrochemical lithium recovery system. In this work, a novel porous disc-like LiMn_(2)O_(4) was successfully synthesized for the first time via two-step annealing manganese(Ⅱ) precursors. The as-prepared LiMn_(2)O_(4) exhibits porous disc-like morphology, excellent crystallinity, high Li^(+)diffusion coefficient(average 7.6×10^(-9)cm^(2)·s^(-1)), high cycle stability(after 30 uninterrupted extraction and release cycles, the crystal structure hardly changed) and superior rate capacity(93.5% retention from 10-120 mA·g^(-1)). The porous structure and disc-like morphology further promote the contact between lithium ions and electrode materials. Therefore, the assembled electrochemical lithium extraction device with LiMn_(2)O_(4) as positive electrode and silver as negative electrode can realize the rapid and selective extraction of lithium in simulated brine(adsorption capacity of lithium can reach 4.85 mg·g^(-1) in 1 h). The mechanism of disc-like LiMn_(2)O_(4) in electrochemical lithium extraction was proposed based on the analysis of electrochemical characterization and quasi in situ XRD. This novel structure may further promote the practical application of electrochemical lithium extraction from brine.

In Search of Portable Water Supplies within a Brine and Mine Water-Invaded Region for Serving Some Communities around Ishiagu, Afikpo and Environs in Abakaliki Basin, Southeast Nigeria

The study investigates the hydrogeochemical characteristics of some towns in the Abakaliki Basin, comprising, Ishiagu, Aka Eze, Amaseri, Afikpo and Okposi communities, with the aim of sourcing for portable water in the area. The basin is underlain by Albian sediments, essentially shales, in the lowlands, which were affected by low-grade metamorphism that had produced slates. The highlands comprise basic intrusives from episodes of magmatism and metallic ore mineralisation. Injection of brines into the aquifer system and low, seasonal aquifer recharge from rainfall results in poor water quality in the area. The study analyzes the geochemical distribution in water sources in the area and identifies sources of pollutants to guide the better choice of portable water. Results of hydrogeochemical analysis of both surface and groundwater from the communities were compared with World Health Organization to identify portable water locations in the area. While the salt lake at Okposi is the main source of brine intrusion in the study area, the Pb/Zn mine at Ishiagu is the main source of mine-water pollution in the study area. Most chemical parameters, (especially Cl-, Na+, Ca2+, Mg2+, SO42-, HCO3-) maintain high concentrations within the salt lake area, with the values declining away from the salt lake. The main anthropogenic source of pollution in the area, especially at Ishiagu, is the indiscriminate surface mining of lead-zinc without proposer waste management practices. Possible sourcing for portable water in the study area includes a deep borehole at Ishiagu, away from lead-zinc intrusives. At the Okposi axis, searching for portable water in boreholes should target shallower aquifers that do not communicate with the deeper-seated brine zones, likewise targeting zones farther away from these brine-invaded areas. A controlled pumping rate could potentially ensure that the cone of depression was not low enough to reach the brine zone at depth. In addition, desalination could also potentially render the salt water drinkable if properly handled to eliminate the high concentration of salts in the water to the level of acceptable limit by the WHO. Based on the study, the best area to target for portable water in the study area is Afikpo, with most geochemical elements naturally occurring within WHO’s standard concentration while portable water could be harnessed in areas further away from mining sites, especially at deep groundwater.

Brineshrimp致死率生测法筛选九牛造抗癌活性部位

首次采用Ｂｒｉｎｅｓｈｒｉｍｐ致死率生测法检测了九牛造的不同提取组分的抗癌活性，结果表明其根提取组分均具生物活性。

BrineShrimp致死率生物鉴定法对八种民间药活性成分的研究

采用ＴｈｅＢｒｉｎｅＳｈｒｉｍｐＬｃｔａｌｉｔｙＢｉｏａｓｓａｙ法对民间药翼蓼ＰｌｅｒｏｘｙｇｏｎｕｍｇｉｒａｌｄｉｉＤｕｍｍｅｒｅｔＤｉｅｌｓ），金荞麦（Ｆａｇｏｐｙｒｕｍｄｉｂｏｔｒｙｓ（Ｄ．Ｄｏｎ）Ｈａｒａ），齿果酸模（ＲｕｍｅｘｄｅｎｔａｔｕｓＬ．）、巴天酸模（ＲｕｍｅｘｐａｔｉｅｎｔｉａＬ．）、网果酸模（ＲｕｍｅｘｄｉｃｔｙｏｃａｒｐｕｓＢｏｉｓｓｅｔＢｕｈｓｅ）、掌叶大黄（ＲｈｅｕｍｐａｌｍａｔｕｍＬｉｎｎ）、异叶败酱（ＰａｔｒｉｎｉａｈｅｔｅｒｏｐｈｙｌｌａＢｇｅ的甲醇提取物的石油醚、乙醚、乙酸乙酯、正丁醇等的萃取部分和水溶液部分及大自米（Ｎｏｔｈｏｌｉｒｉｏｎｈｙａｃｉｎｔｈｉｎｕｍ（Ｗｉｌｓ．）Ｓｉａｐｆ）生物碱总甙共３６种混合物进行了研究，测试出１４种活性成分，从而为抗癌药物的深入研究提供了科学依据。

Formation of Li Salts from Natural Brines during Isothermal Evaporation at 25℃

Li brines are the primary resources for Li salt industries.Evaporation is necessary to concentrate Li due to its low level of concentration in raw brines.The salt sequences during the evaporation of Li brines,especially the behavior of Li salts,represent key data for solar technologies.However,chemists cannot use any phase diagram to estimate Li salt sequences during evaporation at 25℃.The thermodynamic model proposed by us in 2003 represents the only tool for the prediction of equilibrium conditions during the evaporation of solutions containing Li^+,Na^+,K^+,Mg^2+/Cl^-,SO4^2-,and-H2O components at 25℃.In this paper,the predicted salt sequences of 20 brines are reported.The results indicate that (1) the first crystallized Li salt during evaporation of Li brine varies in brine composition;(2) lithium sulfate is crystallized in many cases initially for brines of magnesium sulfate subtype,while Db4 (Li2SO4 ·K2SO4 ) or Db3 (2Li2SO4 ·Na2SO4 ·K2SO4 ) appears first for sodium sulfate and magnesium sulfate subtypes with lower Mg/Li composition,and the final eutectic point is H+LiC+Lc+Ls+Car;(3) the final eutectic point is H+LiC+Lc+Car for brines of chloride type;and (4) Li content corresponding to the first crystallized Li salt is in the range of 0.43%-1%.These findings enhance our knowledge of Li chemistry and provide insights into solar pond technology of the Li-brine process.

Research Progress about the Mixing Brine Method to Produce Low- Sodium Carnallite from Saline Lake Brine

Mixing brine method,which founded on the commonion effect,is widely used for low-sodium carnallite production.Compared with traditional carnallite preparation techniques,the mixing brine method possess a

钙镁离子EZ-BRINE在线分析

阐述了EZ-BRINE钙镁在线分析仪的原理,提出了分析时的技术指标,介绍了钙镁在线分析仪在离子膜电解盐水系统中的应用情况,总结了该分析仪为新疆中泰化学股份有限公司米东氯碱厂树脂塔和离子膜的长周期平稳运行提供的安全保障。

Degree of Brine Evaporation and Origin of the Mengyejing Potash Deposit：Evidence from Fluid Inclusions in Halite

The Mengyejing potash deposit is located in the southern port of the Simao Basin, Yunnan Province, and is hosted in mid-Cretaceous strata. The chemical compositions of fluid inclusions in halite crystals, collected from the level-610 adit in the deposit, were analysed by laser ablation inductively coupled plasma mass spectrometry（LA-ICP-MS）. The results show that the brine is of the Na-K-Mg-Ca-Cl type and has K concentrations that are distinctly higher than those of Mg and Ca, unlike normal brines associated with Cretaceous halite. The high K concentrations indicate that the degree of evaporation of the ancient Mengyejing saline lake was very high, reaching the sylvite deposition stage but rarely reaching the carnallite deposition stage. The trajectory of the H and O isotopic compositions of the brines in the halite-hosted fluid inclusions corresponds to intense evaporation, indicating that the net evaporation exceeded the net inflow of brines. These brine compositions in halite-hosted fluid inclusions were likely formed by the dissolution of previously deposited K-bearing minerals by fresh continental and/or seawater, forming a type of modified seawater, with deep hydrothermal fluids potentially supplying additional potassium. The basin likely experienced multiple seawater incursion, dissolution and redeposition events in a high-temperature environment with high evaporation rates.

Highly efficient extraction of lithium from salt lake brine by LiAl-layered double hydroxides as lithium-ion-selective capturing material

The extraction of lithium from salt lake brine in the Chinese Qaidam Basin is challenging due to its high Mg/Li and Na/Li ratios. Herein, we utilized a reaction-coupled separation technology to separate sodium and lithium ions from a high Na/Li ratio brine(Na/Li = 48.7, w/w) and extracted lithium with Li Al-layered double hydroxides(Li Al-LDHs). The Li Al-LDHs act as lithium-ion-selective capturing materials from multication brines. That is, the lithium ions selectively enter the solid phase to form Li Al-LDHs, and the sodium ions are still retained in the liquid phase. This is because the lithium ions can be incorporated into the structural vacancies of LiAl-LDHs, whereas the sodium ions cannot. The effects of reaction conditions on lithium loss and separation efficiency were investigated at both the nucleation and the crystallization stage, e.g., the nucleation rotating speed, the Li/Al molar ratio, the crystallization temperature and time, and co-existing cations. The lithium loss is as low as 3.93% under optimal separation conditions.The sodium ions remained in the solution. Consequently, an excellent Na/Li separation efficiency was achieved by this reaction-coupled separation technology. These findings confirm that LiAl-LDHs play a critical function in selectively capturing lithium ions from brines with a high Na/Li ratio, which is useful for the extraction of lithium ions from the abundant salt lake brine resources in China.

采用BSLB(Brine Shrimp Letality Bioassay)法对元宝枫 (Acer truncatum Bunge .)及同属植物活性部位的筛选(英文)

本文通过BSLB法对元宝枫及同属植物不同部位的水提物进行了活性试验 ,得知 :元宝枫的幼技、种皮的水提物具一定的生物致死活性 ;同属植物青榨槭叶和种子 ,秦岭槭、杈叶槭果翅的水提物也具一定的生物致死活性。

Anti-bacterial activity and brine shrimp lethality bioassay of methanolic extracts of fourteen different edible vegetables from Bangladesh

Objective:To investigate the antibacterial and cytotoxic activity of fourteen different edible vegetables methanolic extract from Bangladesh.Methods:The antibacterial activity was evaluated using disc diffusion assay method against 12 bacteria(both gram positive and gram negative).The plant extracts were also screened for cytotoxic activity using the brine shrimp lethality bioassay method and the lethal concentrations(LC_(50))were determined at confidence intervals by analyzing the data on a computer loaded with"Finney Programme??Results:All the vegetable extracts showed low to elevated levels of antibacterial activity against most of the tested strains(zone of inhibition=5-28 mm).The most active extract against all bacterial strains was from Xanthium indicum which showed remarkable antibacterial activity having the diameter of growth inhibition zone ranging from 12 to 28 mm followed by Alternanthera sessilis(zone of inhibition=6-21 mm).All extracts exhibited considerable general toxicity towards brine shrimps.The LC_(50)value of the tested extracts was within the range of 8.447 to 60.323μg/mL with respect to the positive control(vincristine sulphate)which was 0.91μg/mL.Among all studied extracts,Xanthium indicum displayed the highest cytotoxic effect with LC_(50)value of 8.447μg/mL.Conclusions:The results of the present investigation suggest that most of the studied plants are potentially good source of antibacterial and anticancer agents.

Corrosion Behaviors of P110 Steel and Chromium Coating in CO_2-saturated Simulated Oilfield Brine

The protective chromium coating was prepared on P110 steel by employing pack cementation.The corrosion behaviors of P110 steel and the obtained coating in CO2-saturated simulated oilfield brine were studied by static complete immersion tests and electrochemical measurements.The corrosion attacks of the samples were determined by mass loss,corroded surface morphologies,corrosion products,and results of electrochemical measurements.The experimental results showed that the coating was uniform,continuous and compact.The chromium coating was slightly corroded,and the mass loss and corrosion rate of the coating were far lower than those of P110 steel.Chromium coating has higher self-corroding potential and lower corrosion current density than P110 steel in accordance with the electrochemical tests results.Taken as a whole,chromizing treatment has significantly improved the corrosion resistance of P110 steel.

Minimizing chemical interference errors for the determination of lithium in brines by flame atomic absorption spectroscopy analysis

Chemical interferences （ionization and oxide/hydroxide formation） on the atomic absorbance signal of lithium in FAAS analysis of brine samples are elaborated in this article. It is suggested that inadequate or overaddition of deionization buffers can lead to loss of sensitivities under particular operating conditions. In the analysis of brine samples, signal enhancing and oxide/hydroxide formation inducing signal reduction resulting from overaddition of deionization buffers can be seen with varying amounts of chemical buffers. Based on experimental results, the authors have arrived at the optimized operating conditions for the detection of lithium, under which both ionization and stable compound formation can be suppressed. This is a simplified and quick method with adequate accuracy and precision for the determination of lithium in routine brine samples from chemical plants or R＆D laboratories, which contain comparable amounts of lithium with some other components.

Manufacture of Boron-free Magnesia with High Purity from Residual Brine

A novel method for removing boron with ion exchange resin from residual brines to manufacture boron-free magnesia is described. The concentration of boron in the target magnesia manufactured thereby from Qinghai salt lakes is lower than 5 mg/g, and the typical D50 size of product is 10.625 mm.

The tempo-spatial characteristics and forming mechanism of Lithium-rich brines in China

With the technological development of exploitation and separation,the primary source of lithium has gradually changed from ore to brine,which has become the main raw material,accounting for more than 80% of the total production.Resources of lithium-bearing brine are abundant in China.This paper has summarized the spatial and temporal distribution,characteristics,and formation mechanism of the lithium-rich brine in China,aiming to provide a comprehensive set of guidelines for future lithium exploitation from brines.Lithium brines usually exist in modem saline lakes and deep underground sedimentary rocks as subsurface brines.The metallogenic epoch of China's lithium-rich brine spans from the Triassic to the Quaternary,and these brines exhibit obvious regional distribution characteristics.Modem lithium-rich saline lakes are predominately located in the Qinghai-Tibet Plateau.In comparison,the subsurface lithium-rich brines are mainly distributed in the sedimentary basins of Sichuan,Hubei,Jiangxi,and the western part of the Qaidam Basin.Lithium-rich saline lakes are chloride-enriched,sulfate-enriched,and carbonateenriched,while the deep lithium-rich brines are mainly chloride-enriched.On the whole,the value of Mg/Li in deep brine is generally lower than that of brine in saline lakes.The genesis of lithium-rich brines in China is not uniform,generally there are two processes,which are respectively suitable for salt lakes and deep brine.

Salt-Gathering and Potassium Formation of Potassium-Rich Brine during the Triassic in the Sichuan Basin, China

Potassium-rich brine in the Sichuan Basin has been much studied in recent years, but few studies have focused on the distribution and migration of salt basin and the differences of potassium formation mechanisms. This work examined the salt-gathering and potassium formation of potassiumrich brine during the Triassic in the Sichuan Basin using lithofacies palaeogeographic depiction and geochemical analyses.(1) The favorable sedimentary facies controlling the formation of potassium-rich brine during the Triassic in the Sichuan Basin are evaporation platform and restricted platform, whereas the salt basin is one of the main factors controlling the poly-salt center.(2) The distribution and migration of this salt basin were affected by certain factors. The salt basin of the Jialingjiang Formation was mainly distributed in the east and central Sichuan Basin, whereas that of the Leikoupo Formation was mainly distributed in the central and west Sichuan Basin. The sedimentary centers have gradually moved westward and become smaller.(3) Three main formation mechanisms were identified for the potassium-rich brine during the Triassic in the Sichuan Basin, i.e., evaporation and concentration of seawater, surface fresh water leaching, and deep water-rock reaction. Fresh water leaching was characterized by low anomaly δ18 O and δ13 C values. Water-rock reaction was mainly related to temperature, and high temperature environment(caused by burial depth, overthrust and deep hydrothermal fluids) was beneficial to water-rock reaction. The characteristics of water-rock reaction do not correspond to the increase ratio of K·103/Cl and Br·103/Cl in brine, and the Rb+ content of the brine was high.(4) The formation mechanisms of potassium-rich brine differed between different areas of the Sichuan Basin. In east Sichuan, the evaporation and concentration of seawater, together with meteoric fresh water leaching, was the main formation factor, whereas the evaporation and concentration of seawater and water–rock reaction predominated in west Sichuan. This study of the sedimentary environment and formation mechanisms is of significance to the exploration and exploitation of potassium-rich brine in the Sichuan Basin.

EQUATION OF STATE BASED HYDRATE MODEL FOR NATURAL GAS SYSTEMS CONTAINING BRINE AND POLAR INHIBITOR

1 INTRODUCTIONIn the past two decades,as large reserves of hydrocarbons were discovered in the formof natural gas hydrates stored in deep oceans and permafrost regions such reserves mayturn out to become a tremendous energy source in the future.Among the challengingproblems emerged from offshore oil/gas exploration and production,hydrate research re-ceived new impetus.