Gallium resin extraction - From "Looking for a needle in a haystack" to "Precise Capture"

Gallium resin is a specially designed ion exchange resin that selectively adsorbs gallium ions through functional groups. Its working principle is based on:

Specific adsorption principle

The surface of gallium resin is modified with special functional groups (such as amino phosphonic acid groups and hydroxamic acid groups), and the spatial configuration and electronic distribution of these groups form a "key-key match" with Ga³⁺ ions. They can selectively form stable coordination bonds with gallium ions, but have a relatively weak affinity for common ions in solution such as aluminum, zinc and iron, achieving precise recognition at the molecular level.

Adsorption-desorption cycle

Adsorption stage: The gallium-containing solution flows through the resin bed, and gallium ions are "captured"

Desorption stage: Use a specific eluent (such as dilute acid or alkali solution) to "release" gallium from the resin

Resin can be reused hundreds of times and is highly economical

Gallium extraction system by alkali method

Adsorption mechanism: Chelation, forming complexes with metallic gallium

Effective group: harmonic amine oxime group

Gallium absorption capacity: ≥3.5g/L

Gallium extraction system by acid method

Chelation mechanism: Capture Ga³⁺

Active group: harmonic amine oxime

Gallium absorption capacity: ≥7.5g/L

It has high selectivity for Ga³⁺ and large adsorption capacity

The alkali and acid methods for extracting gallium resin represent two distinct chemical philosophies and engineering technology approaches:

Alkaline resin is a model of large-scale industrial application. It is closely integrated with the mature alumina industry, embodying the integrated thinking of process industry. The core of its technology lies in maintaining stability in extreme chemical environments and precisely identifying minor differences.

Acid-based resins demonstrate the refined development of resource recycling technology. In the face of complex and variable secondary resources, they require stronger adaptability and higher separation accuracy, representing the cutting-edge exploration of separation science.