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：Manganese lithium ion sieve is suitable for extracting lithium from salt lakes with high magnesium lithium ratio in China. MnO2·0.5H2O lithium ion sieve were synthesized from three different manganese sources: MnSO4, MnOOH and Mn3O4. The products were characterized by X-ray diffraction（XRD）,scanning electron microscope（SEM）, special surface area analysis（the BET method）, and atomic absorption spectrometer（AAS）.The experimental results show that the three manganese sources can synthesize relatively pure Li1.6Mn1.6O4 ion sieve precursors. After acid pickling, the BET specific surface areas of the three lithium ion sieves have increased significantly compared with the precursors, with increments of 546.6%, 129.9% and 142.2% respectively. Among them, the ion sieve synthesized by MnSO4 has the largest specific surface area, and the ion sieve synthesized by Mn3O4 has a special rod shape. The adsorption results showed that the lithium adsorption capacity of the ion sieve synthesized by MnSO4 source was the highest. In the low lithium solution with a concentration of only 20 mg/L, the lithium extraction capacity was 19 mg/g. MoreReset [ABSTRACT FROM AUTHOR]

Lithium is a national strategic resource, and the high-efficiency separation of lithium and magnesium in Salt Lake is the key to ensure the sustainable utilization of lithium resources in China. It is vital important to develop a highly stable lithium ion adsorbent. In this work, Li 2 TiO 3 is synthesized by calcination TiO 2 and Li 2 CO 3 , then which is ion-exchanged with HCl solution to obtain H 2 TiO 3. The experimental results show that hollow structure H 2 TiO 3 has a large pore volume (2.67 cm3/g) and specific surface area (111.57 m2/g). The lithium adsorption performance is systematically investigated by using it as an adsorbent to recover of Li+ from aqueous solution. The adsorption experiments results show that high solution pH environment is more beneficial to adsorb of Li+, and the maximum adsorption capacity of 36.2 mg/g is obtained at pH=13. The results of kinetic experiments indicate that the adsorption behavior of Li+ conforms to the pseudo-second-order model, demonstrating the adsorption process is chemosorption. Additionally, Li+ adsorption conforms to the Langmuir model, indicating adsorption behavior is monolayer adsorption. The thermodynamic experimental results show that the higher temperature is beneficial to Li+ adsorption, and the Gibbs free energy Δ G ϴ of the adsorption process is negative, indicating that the adsorption process is spontaneous. Meanwhile, Δ H ϴ is greater than zero, indicating the process is endothermic. The results of ion selectivity experiments show that H 2 TiO 3 has a high selectivity for Li+ (2.91 mmol·g−1) in a mixed solution contains of Li+, Na+, K+, Rb+ and Cs+. The sorption capacity of H 2 TiO 3 also maintained at 27.55 mg/g after 5 adsorption/desorption cycles, and the dissolution loss rate of titanium is only 0.06 %, indicating the hollow H 2 TiO 3 had a strong structure stability in the process of Li+ adsorption. Therefore, the hollow structure H 2 TiO 3 lithium ion sieve with large adsorption capacity and high stability is a promising adsorbent in the application of lithium extraction from Salt Lake brine. [Display omitted] • H 2 TiO 3 hollow structure with large BET surface area was prepared by using TiO 2 hollow sphere. • The maximum adsorption capacity of Li+ on hollow H 2 TiO 3 is 47 mg/g at 298 K. • The dissolution loss rate of Ti4+ is only 0.06 % after 5 adsorption/desorption cycles. [ABSTRACT FROM AUTHOR]

Jezechake Salt Lake brine in China is rich in lithium ions coexisting with relatively high concentrations of carbonate and borate anions. Both carbonate and borate anions have a pH-buffering ability to accept the exchanged H+ ions of lithium ion sieves, enhancing the adsorption process of Li+ ions. When Jezechake Salt Lake brine passes through a titanium-type ion-sieve-packed column, good lithium breakthrough occurs owing to the pH-buffering action in the brine, which is of great significance for effective lithium recovery from brines in industrial production. In addition, the boron content of Jezechake Salt Lake brine is high, and its recovery is valuable for industrial applications. Here, an N -methylglucamine resin-packed column was connected in series behind a titanium-type ion-sieve-packed column to obtain boron simultaneously with the aim of lowering the energy consumption and cost of lithium recovery. During the adsorption process, Jezechake Salt Lake brine was successively fed into the lithium and boron adsorption columns. The two packed columns were then desorbed independently through acidic solution washing to obtain the Li and B eluents. The breakthrough behavior and elution performance of Li and B in the packed columns were investigated experimentally, and the practicability and efficacy of the proposed process were assessed. • Jezechake Salt Lake brine contains rich carbonate and borate anions coexisting with Li+ ions. • Carbonate and borate in brine have the pH-buffering action to enhance Li+/H+ ion-exchange on lithium ion-sieves. • Good breakthrough behavior of Li+ ions when Jezechake Salt Lake brine passing through the ion-sieves column. • Boron in brine is extracted simultaneously to reduce the energy consumption and cost in lithium recovery. [ABSTRACT FROM AUTHOR]

Lithium is a vital aspect of the strategic development of the alternative energy and nuclear industries, and the demand for this metal is currently increasing rapidly. China possesses significant lithium resources, nearly 80 % of which are situated in salt lake brine. Solvent extraction is a viable means of extracting lithium ions from brine that has high magnesium-to-lithium ratio, and provides high selectivity along with ready scale-up to industrial production levels. The most common extraction technology for such scenarios is the tributyl phosphate (TBP)-FeCl 3 -kerosene system. However, this system tends to lose Fe3+ during the extraction process and the concurrent use of acid and alkali can seriously affect the stability of the organic phase. The present work demonstrates a new extraction process employing TBP as the main extractant, sodium tetraphenyl boron as a co-extractant and phenethyl isobutyrate as a diluent. Optimization of the relative amounts of these components along with the phase ratio provided a single-stage lithium ion extraction efficiency of 85.70 % together with a separation factor of lithium to magnesium ions of 1175. The organic phase was washed with a LiCl + NaCl solution to remove impurity ions then stripped five times with a NaHCO 3 solution, with a Li+ stripping efficiency >99 %. During ten replicate extractions, the Li+ extraction efficiency remained stable at approximately 84 %, demonstrating good stability. NMR spectra verified that the binding strength of metal cations to TBP decreased in the order of Li+ > Na+ ≫ Mg2+, indicating selectivity for the extraction of Li+. This single step NaHCO 3 method was adopted to simplify the extraction process. The overall strategy avoids the use of strong acids or bases that otherwise corrode equipment and provides greatly improved long-term stability of the organic phase. • TBP-sodium tetraphenyl boron-phenethyl isobutyrate extraction system was proposed. • A single-stage extraction efficiency of 85.70 % for lithium ion could be obtained. • The maximum separation factor of lithium to magnesium ions reached up to 1175. • NaHCO 3 was used as stripping agent to simplify the extraction process. • The proposed extraction system showed high stability and reusability. [ABSTRACT FROM AUTHOR]

• Na-Li geothermometer provided by Michard (1990) is relatively suitable for fully equilibrated waters from felsic reservoirs. • The Na-Li ion-exchange equilibrium in thermal waters cannot be reached without a prior Na-K equilibrium. • Small measurement errors of Na and Li concentrations could bring about large deviations for Na-Li geothermometers. • The Li-Mg geothermometer is not recommended for estimating the temperatures of the felsic reservoirs. Lithium-related geothermometers are relatively rarely used because they are based on empirical relations derived from poorly known water-mineral equilibrium reactions and do not always give valid estimations. In this study, we evaluated the applicability of Na-Li and Li-Mg geothermometers based on hydrochemical data for geothermal waters from nine geothermal systems in felsic reservoirs in China. The results indicate that the Na-Li geothermometer provided by Michard (1990), which is similar to those given by Fouillac and Michard (1981) and Verma and Santoyo (1997) with Cl <0.3 mol/L, is suitable for fully equilibrated waters from felsic reservoirs and their estimates better represent the temperatures of the deep rather than the shallow reservoirs. The Na-Li ion-exchange equilibrium in thermal waters cannot be reached without a prior Na-K equilibrium, which ensures that the Na concentration remains constant. Also, variations in the Na-Li ratios may be significantly unpredictable such that the Michard (1990) Na-Li geothermometer may coincidentally give valid temperature estimates for thermal waters from the low-temperature geothermal systems. Furthermore, the Li in the thermal waters may originate from water-mineral reactions or mixing with magmatic water or both. In reservoirs consisting of basalt and felsic rocks, variations in hydrothermal alteration may be the key factor that explains the large differences in Na-Li equilibria in the thermal waters. Additionally, small measurement errors could bring about large deviations in the temperature estimations due to the large difference between Na and Li concentrations in the thermal waters from the felsic reservoirs. Unlike the Li concentration, which remains constant once the thermal waters leave the deep reservoirs, the concentration of Mg in the thermal waters is sensitive to the temperature in the shallow reservoirs. Hence, we discourage the use of the Li-Mg geothermometer for estimating felsic reservoir temperatures. [ABSTRACT FROM AUTHOR]

High concentration of Li, associated with coal, has been found in the Guanbanwusu coal Mine, Inner Mongolia, China. Earlier studies suggested that the lithium came from the Yinshan Paleoland during the peat-forming stage. The results of Li isotope determinations and calculations based on density functional theory (DFT) indicated that the lithium in the peat was released into the pore water and adsorbed by kaolinite edge surfaces (octahedral layers and/or tetrahedral layers) in the subsequent diagenesis and coalification. Alternatively, the Li of the partings, the floor, and the roof of the No. 6 coal seam also likely originated from the underlying bauxite of the Benxi Formation. Specifically, we determined the Li isotopic fractionations produced in chelation by small carboxylate (Δ7/6Li organolithium-aq = −0.35‰), in adsorption onto kaolinite edge surfaces (Δ7/6Li octahedral layer-aq = 4.36‰, Δ7/6Li tetrahedral layer-aq = −4.53‰), and during incorporation into the lattices (Δ7/6Li Al2-aq = −8.2‰ and Δ7/6Li Al1-aq = −11.9‰). Combining these results with the δ7Li of 3.37 ± 0.13‰ for the moyite of the Yinshan Paleoland, we deduced a theoretical δ7Li range for the No. 6 coal seam and the partings, 2.85–7.38‰, exactly covering the determined δ7Li values of the coal and the partings. However, only the partings plotted in the theoretical δ7Li range of 1.13–5.66‰ assuming the bauxites (with δ7Li 1.30 ± 0.03‰) as the lithium source. During weathering and deposition, conversion of structurally incorporated Li within the grain boundaries of polycrystalline minerals of the bauxites to adsorbed Li was inferred to explain the Li isotope excursion in the latter case. • To discuss the Li enrichment in coals by DFT calculations and MC-ICP-MS analyses • The coals and the partings of the No. 6 coal seam may have different Li sources. • Occurrence modes of light element Li in the coals and the partings are inferred. [ABSTRACT FROM AUTHOR]