Self-Assembled Microscale Redox Reactor for Energy-Neutral Uranium Sequestration in Highly Acidic Wastewater

Area of Science:

• Environmental Science
• Materials Science
• Chemistry

Background:

• Uranium (U(VI)) in wastewater from rare-earth tailings is highly soluble and mobile, posing remediation challenges.
• Conventional reduction treatments are energy-intensive and inefficient in acidic environments.

Purpose of the Study:

• To develop an energy-neutral, efficient method for uranium remediation.
• To engineer a material capable of concurrent adsorption and catalytic reduction of U(VI).

Main Methods:

• Fabrication of a self-assembled phytate-Fe-polyaniline (PA-Fe-PANI) composite.
• Utilizing an intrinsic Fe2+/Fe3+ redox cycle for autonomous U(VI) reduction.
• Testing the composite's performance in simulated and actual rare-earth tailings wastewater.

Main Results:

• The PA-Fe-PANI composite demonstrated high uranium adsorption capacity (130.70 mg/g at pH 1.0).
• It effectively reduced U(VI) to immobile U(IV) without external energy input.
• Achieved 96.8% uranium removal from complex industrial wastewater.

Conclusions:

• The PA-Fe-PANI composite functions as an autonomous microscale redox reactor for uranium remediation.
• This approach offers a scalable, chemically stable, and energy-neutral solution for immobilizing uranium in acidic industrial wastewater.