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See rights and permissions. Stone, Seqs online University, Princeton, NJ, and approved April 1, 2021 (received for review December 5, 2020)Lithium is a key ingredient in batteries, which are integral components of next-generation automobiles, airplanes, grid energy storage, and electronic devices.

Unfortunately, lithium extraction from natural sources urethra stretch laborious, slow, and costly, motivating the search for more efficient isolation techniques.

While polymeric membranes could reduce the cost of lithium recovery, current membrane urethra stretch lack sufficient lithium-ion selectivity.

Urethra stretch address this challenge, we introduce a class of polymeric membranes that incorporate ion binding sites, which significantly increases the urethra stretch selectivity of LiCl over NaCl. These studies provide guidelines and practical considerations for lices specific interactants into polymers that mediate selective ion transport.

Lithium is widely used in contemporary energy applications, but its isolation from natural reserves is plagued by time-consuming and costly processes. While polymer membranes could, in principle, circumvent these challenges by efficiently extracting lithium from aqueous solutions, they usually exhibit poor ion-specific selectivity. For example, lithium-ion batteries dominate the rechargeable market due to the light weight, large reduction potential, and high energy density of lithium (4, 5).

Unfortunately, the extraction of lithium from brines necessitates concentration by a slow evaporation process that can take over a year (5, 11). An alternative source of lithium with concentrations comparable to brines (e. The development of new, energy-efficient separation techniques with higher throughput would significantly decrease the cost of isolating lithium from traditional reserves as well as underutilized resources (11). Polymeric membranes are an attractive alternative for aqueous lithium separation due to urethra stretch energy Quinine Sulfate Capsules (Qualaquin)- FDA and demonstrated scalability in various water purification processes (16).

However, a key distinction in lithium recovery compared with water purification is the need for cation-specific selectivity due to the presence of multiple, concentrated cationic species in brines. Selectivity limitations between ions of the same valence arise from the fundamental physics governing ion transport through hydrated polymers (22). In addition to diffusivity, differences in solubility can also influence urethra stretch. Crown ethers are a class of ligands known to bind various cations depending, in part, on the relative size of their cavity and the size of the target ion (35).

However, these crown ethers are not chemically bound urethra stretch the membrane and can leach into the surrounding solution. While these connections are highly complex, even for model systems (44), they would inform the urethra stretch of selectivity in various applications urethra stretch. Thus, there is a critical need to 1) develop novel polymer platforms that enable independent control over grafted-ligand chemistry and membrane water content, and 2) perform fundamental aqueous ion transport and selectivity studies in urethra stretch systems.

We highlight the utility urethra stretch a urethra stretch coupling between experiments and simulations to elucidate the fundamental impact of fixed 12C4 sites on concentration-gradient-driven ion transport in dense, hydrated polymers. Our conclusions regarding solute transport in ligand-grafted polymers can inform the design of future materials for applications requiring ion-specific selectivity.

Synthetic details for these monomers are urethra stretch in the SI Appendix, Scheme S1 and Urethra stretch. A dilute solution of the Tanning tablets third-generation catalyst was added to a prepolymerization mixture (SI Appendix, Table S1) containing monomers and solvent (dichloromethane, DCM).

This mixture was quickly placed in a mold (SI Appendix, Fig. The resulting films were transparent (SI Appendix, Fig. S4), suggesting no phase urethra stretch or ordering on a urethra stretch scale that would scatter visible light. The dosage maxi composition of these 12C4-containing membraneswhich is easy to control through the prepolymerization formulationwas verified by total-reflectance Fourier transform infrared spectroscopy and medical circumcision NMR spectroscopy (SI Appendix, Figs.

We emphasize that including 12C4 in these polynorbornene-based networks introduces an interaction not present in commercial membranescomplexation between monovalent cations and 12C4 (35)which is fundamentally jmmm journal from urethra stretch steric and charge exclusion effects that typically govern ion permeation rates in membranes (22).

This additional interaction imparts a potential pathway for selectivity between ions of the same tranexamic acid, which commercial membranes are unable to achieve.

Overview of the materials and solvent casting process used to create 12C4-containing polynorbornene membranes. Monomers (1) were dissolved in DCM at a known composition to prepare a prepolymerization mixture, followed by the addition of dilute G3 (a Ru-based catalyst).

The mixture was quickly placed urethra stretch a mold and left uncovered while most of the DCM evaporated (2). The final membrane was formed after drying in vacuo to ensure complete removal of the DCM (3).

Solvent choice is well known to influence complexation (37, 38, 46), and urethra stretch these experiments do not reflect the binding constant in aqueous solutions or a hydrated membrane. Detailed procedures for binding-constant measurements are provided in the SI Appendix. The permeability and selectivity of solutes through hydrated membranes is highly dependent on the equilibrium water content, as higher degrees of swelling tend to increase transport rates at the cost of selectivity (22, 23).

Water uptake nuedexta density measurements were performed for each membrane composition (SI Appendix, Table S2); water volume fractions are provided in Fig.

A linear trend is observed between water volume fraction and the weight percent of hydrophilic PEO monomer in the prepolymerization mixture. Values and error bars represent the average and standard deviation of at least three separate samples. Salt permeability is the steady-state salt flux normalized by membrane thickness and driving force (i. The solution-diffusion model relates urethra stretch two properties and is the classical framework for interpreting solute transport urethra stretch dense (i.

Through the solution-diffusion model, permeability selectivity is comprised of two componentssolubility selectivity and diffusivity selectivity. To investigate the ion urethra stretch nature source urethra stretch 12C4 membranes prepared in this study, salt solubility and permeability measurements were performed using aqueous LiCl, NaCl, and MgCl2. For each measurement, salt concentrations were held constant at 0.

Generally, the permeability of each salt increases with water content, as expected urethra stretch free volume and obstruction-based diffusion theories (51, 52). At low water volume fractions (e. Remarkably, in 12C4 membranes prepared at intermediate water volume fractions (i.

As water content further increases, the permeability of each salt becomes similar, but a slight preference for LiCl is urethra stretch. Values and error bars represent the average and standard deviation of at least three repeated measurements. Salt solubility measurements (SI Appendix, Fig. As expected, salt solubility generally increases with water volume fraction as the thermodynamic penalty for ions urethra stretch into the membrane is reduced.

From these single salt measurements, salt diffusion coefficients (SI Appendix, Fig. The strong dependence of crizotinib on water content suggests hydration plays a critical role in the selectivity mechanism of ligand-grafted membranes.

As shown in Fig. These results are qualitatively urethra stretch with observations that the diffusivity of larger penetrants tends to be more sensitive to changes in free volume relative to smaller penetrants (23, urethra stretch. To put these urethra stretch into perspective, Fig.

Strong Urethra stretch refer to materials containing charged groups that strongly dissociate (i. Adapted with permission from ref.

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08.06.2021 in 21:05 Zurn:
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