Iron Recovery from Metal Streams via Organic Chelation

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing methods for recycling valuable metals from process streams contaminated with iron, such as those from battery and catalyst materials, are inefficient and costly due to the strong adsorption of iron by solid phase extractants, which leads to resin poisoning and requires the use of high concentrations of inorganic acids for elution, making it impractical for industrial-scale processes.

Innovation Solution

The use of a solid phase extraction method with a combination of aminomethylphosphonic acid (AMPA) as the solid phase extractant and ethylenediaminetetraacetic acid (EDTA) as the stripping agent to selectively adsorb and desorb iron without the need for concentrated inorganic acids, utilizing a pH-controlled aqueous solution of organic chelating molecules to form a complex with iron.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Object-affected harmful factors

If solid phase extractant material is used to remove iron from process streams, then iron removal efficiency is improved, but the extractant material becomes poisoned and requires replacement

Engineering Contradiction:
Improveiron contaminationVSAvoidextractant material stability
Core Design Contradiction:
Object-affected harmful factorsVSReliability

Solution Approach 1:

An organic chelating agent is introduced as an intermediary substance that temporarily binds to iron on the solid phase extractant material, forming a soluble complex that can be washed away. This mediator enables iron removal without directly attacking the extractant material, preventing poisoning while maintaining extraction efficiency.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent changes the chemical parameters by using mild aqueous solutions (such as dilute acids or chelating agents) instead of harsh concentrated inorganic acids. This parameter change allows iron to be selectively removed from the extractant material under gentle conditions that do not degrade the polymer structure, thereby preventing poisoning.

Inventive Principle:
Principle #35Parameter changes

2Object-affected harmful factors

If concentrated inorganic acids are used to elute iron from solid phase extractants, then iron removal is achieved, but the process becomes impractical for industrial-scale operations

Engineering Contradiction:
Improveiron adsorptionVSAvoidprocess scalability
Core Design Contradiction:
Object-affected harmful factorsVSEase of manufacture

Solution Approach 1:

The patent changes the concentration and type of acid used from concentrated inorganic acids to dilute aqueous solutions or mild chelating agents. This parameter change makes the elution process safer, more cost-effective, and scalable for industrial applications while maintaining effective iron removal capability.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

Instead of using expensive and hazardous concentrated inorganic acids that require special handling and disposal infrastructure, the patent employs cheap, readily available dilute aqueous solutions that can be easily disposed of or regenerated, significantly reducing operational costs and complexity for industrial-scale operations.

Inventive Principle:
Principle #27Cheap short-living objects (Disposable)

3Manufacturing precision

If multiple separate extraction steps are performed to selectively extract metals, then metal purity is improved, but the procedure becomes costly and complex

Engineering Contradiction:
Improvemetal purityVSAvoidextraction procedure complexity
Core Design Contradiction:
Manufacturing precisionVSDevice complexity

Solution Approach 1:

The solid phase extractant material is designed to perform multiple functions: it selectively adsorbs iron from the process stream, allows other valuable metals to pass through in the effluent, and can be regenerated and reused for multiple cycles. This multi-functionality eliminates the need for multiple separate extraction steps while maintaining high metal purity.

Inventive Principle:
Principle #6Universality (Multi-functionality)

Solution Approach 2:

The patent selectively extracts only the unwanted iron component from the process stream using the solid phase extractant material, leaving the valuable metals in the effluent. This selective removal approach simplifies the overall procedure compared to performing multiple extraction steps for each metal component, reducing complexity while achieving the desired purity.

Inventive Principle:
Principle #2Taking out (Extraction)

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

This approach allows for efficient and cost-effective removal of iron from solid phase extractants, making the recovery of valuable metals easier and cheaper by using recyclable materials of construction and reducing environmental impact.

Implementation Method 1

contacting the acidic aqueous recycling feed with a solid phase extractant material which adsorbs the iron

Methodology Applied
Scientific EffectAdsorption: Adsorption

Implementation Method 2

contacting the solid phase extractant material with a stripping agent comprising a solution of organic chelating molecules which form a complex with the iron

Methodology Applied
Scientific EffectChelation: Chemical Bonding

Data Source

PatentEP4405513B1A recycling method for recovery of valuable metal elements from process streams contaminated with iron
Publication Date: 2025.10.08 GELION TECH PTY LTD
  • EP4405513B1 patent drawingFigure 1
  • EP4405513B1 patent drawingFigure 2
  • EP4405513B1 patent drawingFigure 3

AI summary

A method of recycling one or more valuable metal elements from a source material comprising the one or more valuable metal elements, the method comprising: forming an acidic aqueous recycling feed by acid leaching the source material or a derivative thereof, the acidic aqueous recycling feed comprising the one or more valuable metal elements and iron in solution; contacting the acidic aqueous recycling feed with a solid phase extractant material which adsorbs the iron, the one or more valuable metal elements remaining in solution; recovering the one or more valuable metal elements from the acidic aqueous recycling feed via one or more further process steps selected from solvent extraction, solid phase extraction, electrochemical extraction, and precipitation processes; and recovering the iron from the solid phase extractant material by contacting the solid phase extractant material with a stripping agent comprising a solution of organic chelating molecules which form a complex with the iron.