An ion exchange chromatography column contains an ion exchange stationary phase that includes a charged substrate, a plurality of first particles, and a plurality of second particles. The plurality of first particles each include first ion exchange groups and the first particles are ionically bound to the charged substrate. The plurality of second particles each include second ion exchange groups and the second particles are ionically bound to the charged substrate. The first particles having a first ion exchange group density, and the second particles having a second ion exchange group density. The first ion exchange group density is greater than the second ion exchange group density. The ion exchange chromatography column has a number of zones connected in series where each zone can have a varying level of first ion exchange groups and second ion exchange group from the inlet zone to the outlet zone.

An ion exchange chromatography column contains an ion exchange stationary phase that includes a charged substrate, a plurality of first particles, and a plurality of second particles. The plurality of first particles each include first ion exchange groups and the first particles are ionically bound to the charged substrate. The plurality of second particles each include second ion exchange groups and the second particles are ionically bound to the charged substrate. The first particles having a first ion exchange group density, and the second particles having a second ion exchange group density. The first ion exchange group density is greater than the second ion exchange group density. The ion exchange chromatography column has a number of zones connected in series where each zone can have a varying level of first ion exchange groups and second ion exchange group from the inlet zone to the outlet zone.

An ion exchange chromatography column contains an ion exchange stationary phase that includes a charged substrate, a plurality of first particles, and a plurality of second particles. The plurality of first particles each include first ion exchange groups and the first particles are ionically bound to the charged substrate. The plurality of second particles each include second ion exchange groups and the second particles are ionically bound to the charged substrate. The first particles having a first ion exchange group density, and the second particles having a second ion exchange group density. The first ion exchange group density is greater than the second ion exchange group density. The ion exchange chromatography column has a number of zones connected in series where each zone can have a varying level of first ion exchange groups and second ion exchange group from the inlet zone to the outlet zone.

A major challenge in the development of anion exchange membranes for fuel cells is the design and synthesis of highly stable (chemically and mechanically) and conducting membranes. Membranes that can endure highly alkaline environments while rapidly transporting hydroxides are desired. A design for using cross-linked polymer membranes is disclosed to produce ionic highways along charge delocalized pyrazolium and homoconjugated triptycenes. The ionic highway membranes show improved performance in key parameters. Specifically, a conductivity of 111.6 mS cm.sup.1 at 80 C. was obtained with a low 7.9% water uptake and 0.91 mmol g.sup.1 ion exchange capacity. In contrast to existing materials, these systems have higher conductivities at reduced hydration and ionic exchange capacities, emphasizing the role of the highway. The membranes retain more than 75% of initial conductivity after 30 days of alkaline stability test. This effective water management through ionic highways is confirmed by density functional theory and Monte Carlo studies. A single cell with platinum group metal catalysts at 80 C. showed a high peak density of 0.73 W cm.sup.2 (0.45 W cm.sup.2 from silver-based cathode) and stable performance during 400 h tests.

A major challenge in the development of anion exchange membranes for fuel cells is the design and synthesis of highly stable (chemically and mechanically) and conducting membranes. Membranes that can endure highly alkaline environments while rapidly transporting hydroxides are desired. A design for using cross-linked polymer membranes is disclosed to produce ionic highways along charge delocalized pyrazolium and homoconjugated triptycenes. The ionic highway membranes show improved performance in key parameters. Specifically, a conductivity of 111.6 mS cm.sup.1 at 80 C. was obtained with a low 7.9% water uptake and 0.91 mmol g.sup.1 ion exchange capacity. In contrast to existing materials, these systems have higher conductivities at reduced hydration and ionic exchange capacities, emphasizing the role of the highway. The membranes retain more than 75% of initial conductivity after 30 days of alkaline stability test. This effective water management through ionic highways is confirmed by density functional theory and Monte Carlo studies. A single cell with platinum group metal catalysts at 80 C. showed a high peak density of 0.73 W cm.sup.2 (0.45 W cm.sup.2 from silver-based cathode) and stable performance during 400 h tests.

The invention discloses a functionalised chromatography medium, comprising: i) at least one non-woven layer (10) of polymeric nano fibres (20) comprising a plurality of nanofibre-nano fibre fusion points (30); ii) a grafted polymer coating covering the polymeric nanofibres and the nanofibre-nanofibre fusion points; iii) a plurality of ligand groups covalently bound to the grafted polymer coating, wherein the ligand groups are capable of interacting with a target biomolecule.

The invention discloses a functionalised chromatography medium, comprising: i) at least one non-woven layer (10) of polymeric nano fibres (20) comprising a plurality of nanofibre-nano fibre fusion points (30); ii) a grafted polymer coating covering the polymeric nanofibres and the nanofibre-nanofibre fusion points; iii) a plurality of ligand groups covalently bound to the grafted polymer coating, wherein the ligand groups are capable of interacting with a target biomolecule.

Methods for the removal of ionic contaminants from hydrolysable organic solvent by ion exchange resins are described. A mixed bed of ion exchange resin with cationic ion exchange resin and weak-base anionic ion exchange resin is used in such methods.

Methods for the removal of ionic contaminants from hydrolysable organic solvent by ion exchange resins are described. A mixed bed of ion exchange resin with cationic ion exchange resin and weak-base anionic ion exchange resin is used in such methods.

A method for recovering water from purified terephthalic acid production wastewater includes: producing purified terephthalic acid comprising purified terephthalic acid feedstock and wastewater comprising impurities; separating the purified terephthalic acid feedstock from the wastewater comprising impurities; transferring the wastewater to a tank; adjusting the p H of the wastewater with a basic solution; adjusting the temperature of the wastewater; passing the wastewater to a column; contacting the wastewater with an ion exchange resin to remove the impurities; and recovering the water depleted of impurities.