ion exchange resin

Pd n clusters offer unique selectivity and exploitable reactivity in catalysis. Understanding the behavior of Pd n clusters is thus critical for catalysis, applied synthetic organic chemistry and greener outcomes for precious Pd. The Pd3 cluster, [Pd3 (μ-Cl)(μ-PPh2 )2 (PPh3 )3 ][Cl] (denoted as Pd3 Cl2 ), which exhibits distinctive reactivity, was synthesized and immobilized on a phosphine-functionalized polystyrene resin (denoted as immob-Pd3 Cl2 ). The resultant material served as a tool to study closely the role of Pd3 clusters in a prototypical Suzuki-Miyaura cross-coupling of 4-fluoro-1-bromobenzene and 4-methoxyphenyl boronic acid at varying low Pd ppm concentrations (24, 45, and 68 ppm)...

In this study, the hybrid biological ion exchange (BIEX) resin and gravity-driven membrane (GDM) process was employed for the treatment of coloured and turbid river water. The primary objective was to investigate the impact of both physical and chemical cleaning methods on ceramic and polymeric membranes in terms of their stabilised flux, flux recovery after physical/chemical cleaning, and permeate quality. To address these objectives, two types of MF and UF membranes were utilised (M1 = polymeric MF, M2 = polymeric UF, M3 = ceramic UF, and M4 = lab-made ceramic MF)...

Plasma protein therapies are used by millions of people across the globe to treat a litany of diseases and serious medical conditions. One challenge in the manufacture of plasma protein therapies is the removal of salt ions (e.g., sodium, phosphate, and chloride) from the protein solution. The conventional approach to remove salt ions is the use of diafiltration membranes (e.g., tangential flow filtration) and ion-exchange chromatography. However, the ion-exchange resins within the chromatographic column as well as filtration membranes are subject to fouling by the plasma protein...

Tropic acid was synthesized in a good yield and with high enantioselectivity (81% ee) under non-biphasic conditions via the novel hydrolytic dynamic kinetic resolution of racemic 3-phenyl-2-oxetanone (tropic acid β-lactone) in the presence of a chiral quaternary ammonium phase-transfer catalyst and strongly basic anion exchange resin as the hydroxide ion donor.

Opioid misuse is a public health crisis in the United States. In response, the FDA has approved drug products with abuse-deterrent features to reduce the risk of prescription opioid abuse. Abuse-deterrent formulations (ADFs) typically employ physical or chemical barriers or incorporate agonist-antagonist combinations as mechanisms to deter misuse. This study aims to assess the impact of abuse-deterrent properties, specifically ion-exchange resin complexation as a chemical barrier, on a model drug, promethazine hydrochloride (PMZ) tablets...

The spherical materials TiO2 -SiO2 -P2 O5 /CaO, TiO2 -SiO2 -P2 O5 /La2 O3 , and TiO2 -SiO2 -P2 O5 /ZnO deposited on the Tokem-250 cation exchanger have been synthesized with an alcoholic solution by the sol-gel method. The macroporous cation exchanger Tokem-250, which has high Ca2+ , Zn2+ , and La3+ ion selectivity, was used in the present study. This material has the ability to precipitate and mineralize calcium phosphates on its surface in biological media, since it has high porosity, a homogeneous structure with a uniform variation of elements, and the presence of active centers (Si4+ , Ti4+ ) on the surface...

High-performance proton exchange membrane (PEM) is crucial for the proton exchange membrane fuel cell (PEMFC). Herein, a novel "self-enhanced" PEM is fabricated for the first time, which is composed of perfluorinated sulfonic acid (PFSA) resin and its own nanofibers as reinforcement. With this strategy, the interfacial compatibility issue of conventional fiber-reinforced membranes is fully addressed and up to 80 wt% loading of PFSA nanofibers can be incorporated. Furthermore, on account of chain orientation within the PFSA nanofiber, single fiber exhibits super-high conductivity of 1...

A novel tandem affinity tag is presented that enables the use of cation exchange resins for initial affinity purification, followed by an additional column step for enhanced purity and affinity tag self-removal. In this method, the highly charged heparin-binding tag binds strongly and selectively to either a strong or weak cation exchange resin based on electrostatic interactions, effectively acting as an initial affinity tag. Combining the heparin-binding tag (HB-tag) with the self-removing iCapTag™ provides a means for removing both tags in a subsequent self-cleaving step...

Selectivity with respect to chloride (<mml:math xmlns:mml="https://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msub><mml:mi>K</mml:mi><mml:mrow><mml:mtext>PFAS</mml:mtext><mml:mo>∕</mml:mo><mml:mi>C</mml:mi></mml:mrow></mml:msub></mml:mrow></mml:math>) was determined for nine drinking water relevant perfluoroalkyl and polyfluoroalkyl substances (PFAS): perfluoro-2-propoxypropanoic acid (GenX), five perfluoroalkyl carboxylic acids (PFCAs), and three perfluoroalkyl sulfonic acids (PFSAs)...

In nature, many organisms are capable of self-organizing into collective groups through local communications to perform complex tasks that individuals cannot complete. To date, the reported artificial microswarms either rely on toxic chemical reactions for communication or lack the hierarchical controllability and functionality, which is unfavorable for practical applications. To this end, this exploits the ion-exchange reaction enabled hierarchical swarm composed of cationic ion exchange resin and magnetic microspheres of internal information exchange...

The red microalga Galdieria sp. is an extremophile that inhabits acidic hot sulphur springs and grows heterotrophically to a high cell density. These characteristics make Galdieria suitable for commercial applications as stable mass production is the key to success in the algae business. Galdieria has great potential as a precious metal adsorbent to provide a sustainable, efficient and environmentally benign method for urban mining and artisanal small-scale gold mining. The efficiency and selectivity in capturing precious metals, gold and palladium from metal solutions by a Galdieria -derived adsorbent was assessed relative to commercially used adsorbents, ion exchange resin and activated charcoal...

The use of a resin to selectively separate thiomolybdate from a tungsten (W) feed solution is a well-known protocol for achieve high-purity W products; however, the regeneration of saturated resin is laborious. In this study, poly(diallyl dimethyl ammonium chloride) (PDADMA) was used to modify ultrasound-pretreated montmorillonite (Mt) for W and molybdenum (Mo) separation for the first time, and the resultant tetrathiomolybdate (MoS4 2- )-loaded composite was further tested to remove heavy metals instead of regeneration...

Recombinant adeno-associated virus (AAV) has emerged as one of the most promising systems for therapeutic gene delivery and has demonstrated clinical success in a wide range of genetic disorders. However, manufacturing of high-quality AAV in large amounts still remains a challenge. A significant difficulty for downstream processing is the need to remove empty capsids that are generated in all currently utilized expression systems and that represent product-related impurities that adversely affect safety and efficacy of AAV vectors...

The challenge of meeting discharge standards for tetrabromobisphenol A (TBBPA) production wastewater, characterized by high concentrations of organic by-products, necessitates effective treatment methods. This study identifies 2,4-dibromophenol, 2,6-dibromophenol, 2,4,6-tribromophenol, chlorobenzene, and toluene as the primary organic by-product pollutants. A coagulation-centered three-step approach was established for TBBPA industrial wastewater treatment. The initial step involves acidification treatment to exploit the reduced solubility of 2,4-dibromophenol, 2,6-dibromophenol, and 2,4,6-tribromophenol under acidic conditions, with the optimal pH determined as 2...

Materials composed of natural zeolite have the potential to serve as highly effective adsorbents in the treatment of wastewater. The present study explores zeolite resin-based Apophyllite and Thomsonite as adsorbents for removing Zinc from acid mine drainage solution. The characteristics of the natural zeolites (Apophyllites and Thomsonite) are investigated using X-ray diffraction, Fourier-transform infrared spectroscopy and Field emission scanning electron microscopy analysis. The removal of Zinc from AMD is explored, and the influence of metal ion concentration, resin dose, and pH is investigated using a batch exchange resin-based experimental method...

Capacitive deionization (CDI), an emerging method to eliminate ions from water at a low cost, has garnered significant interest in recent years. This study evaluates the implication of cation exchange resin loading on the membrane via the nonsolvent-induced phase inversion method. After determining the quantity of resins efficiently loaded on the membrane, it was subsequently utilized as a cation exchange membrane in the membrane capacitive deionization (MCDI) unit to examine the performance removal of Ni2+ ...

This paper presents the results of an analysis of the porous structure of spherical activated carbons obtained from cation-exchange resin beads subjected to ion exchange prior to activation. The study investigated the effects of the type of cation exchange resin, the concentration of potassium cations in the resin beads and the temperature of the activation process on the adsorption properties of the resulting spherical activated carbons. The numerical clustering-based adsorption analysis method and the quenched solid density functional theory were used to analyse the porous structure of spherical activated carbons...

This study focused on the preparation of a highly efficient activated carbon adsorbent from waste cation exchange resins through one-step carbonization to remove ciprofloxacin (CIP) from aqueous solutions. Scanning electron microscopy, X-ray diffraction, Fourier-transform infrared spectrometry, and X-ray photoelectron spectroscopy were used to characterize the physicochemical properties of the carbonized materials. The CIP removal efficiency, influencing factors, and adsorption mechanisms of CIP on the carbonized resins were investigated...

In this study, the optimal fabrication parameters of a heterogeneous anion-exchange membrane (AEM) using an ionomer binder are investigated to improve the performance of continuous electrodeionization (CEDI) for producing ultrapure water. Poly(2,6-dimethyl-1,4-phenylene oxide) (PPO) is selected as the base material for preparing the ionomer binder and quaternized to have various ion exchange capacities (IECs). The optimal content of ion-exchange resin (IER) powder according to the IEC of the ionomer binder is then determined through systematic analyses...

Novel anion-exchange electrospun fiber membranes of polycaprolactone doped with the cationic, cross-linked colesevelam polymer are reported. The weight fraction of cross-linked cationic colesevelam polymer, as the active phase within the PCL matrix, can readily be controlled in the synthesis of the mixed-matrix fibers (Cole@PCL), enabling optimization of the ion-exchange properties of the resulted membranes. This approach enabled adaptation of anion-exchange resins to a permeable, flexible membrane form, which is a significant advancement toward futuristic water treatment applications, demonstrated herein for the removal of trace contaminants, including nitrates and phosphates, as well as anionic dyes...