Selective Adsorbent & Scavenger Technology
IEX designs and manufactures selective adsorbent materials, commonly known as scavengers, for the targeted capture of metal ions and other species from liquid process streams.
What Are Scavengers?
Scavengers are solid functional materials designed to selectively bind to specific ions in solution.
Think of them as chemical magnets: solid particles – the ‘backbone’ - are coated (functionalised)_with (quadrillions) of chemical functional groups, tailored to attract and hold a specific target species from the liquid passing through or around them.
When a liquid containing the target ion contacts the scavenger, the ions migrate to the surface of the solid and bind to the functional groups. The result is the target species captured on the solid phase and a depleted liquid phase.
The physical characteristics of the backbone material matter too. Particle size, shape, porosity, and surface area all influence how quickly and completely ions are captured, and how the material performs at scale and under real operating conditions.
IEX manufactures scavengers based on a range of solid backbones including silica, polymer, alumina, and activated carbon supports, each with different performance characteristics suited to different process conditions.
How Selectivity Works
The selectivity of a scavenger comes from functional groups attached to its surface. By choosing the right functional group chemistry for the target ion, IEX can design materials that preferentially capture the species of interest while leaving others largely unaffected. Selectivity is achieved by exploiting the chemical differences and similarities between ionic species and is influenced by the charge on the ion, ionic radius, chemical affinities and pore size of the backbone material.
This selectivity is what makes scavengers valuable in complex process streams where multiple species are present.
Material Options
Silica-Supported Materials
Silica provides a rigid, thermally stable scavenger suited to high-temperature applications and organic solvent environments. Silica-based scavengers do not swell in solvents, making them well suited to non-aqueous process streams. They are available in a wide range of porosity, particle shapes and sizes and can be easily tailored to individual applications. Silica scavengers are less suited to highly alkaline conditions where silica can dissolve.
Alumina-Supported Materials
Alumina supports offer a further alternative scavenger for specific process chemistry and conditions, for example where silica leaching at ppm levels is undesirable.
Polymer-Supported Materials
Polymer scavengers offer cost-effective scavenging across a wide range of applications and have been widely adopted and a large body of application knowledge is readily available. Polymer scavengers are well suited to water-based streams but can swell or degrade inorganic solvents, which limits their use in some non-aqueous environments. Operating temperature range is more limited than silica.
Activated Carbon-Supported Materials
Activated carbon provides a high surface area scavenger with speciality applications where suited to broad-spectrum capture or where the process chemistry is not compatible with silica or polymer supports.
From Material to Solution
Selecting the right scavenger is the starting point, not the end point.
Performance in the lab does not automatically translate to performance at scale in a live process environment.
IEX combines material expertise with process development capability, moving from initial screening and selection through to validated, deployable solutions.
Talk to the IEX Technical Team
If you are ready to deploy a scavenger solution or want to understand which deployment option is right for your process, speak to the IEX technical team.