Interface-Constrained Layered Double Hydroxides for Stable Uranium Capture in Highly Acidic Industrial Wastewater

Area of Science:

• Materials Science
• Environmental Chemistry
• Nanotechnology

Background:

• Layered double hydroxides (LDHs) exhibit limited acid endurance, hindering uranium(VI) [U(VI)] adsorption from acidic industrial wastewater.
• Developing robust adsorbents is crucial for effective uranium remediation in harsh environments.

Purpose of the Study:

• To engineer magnesium-cobalt LDHs (Mg-Co LDHs) anchored onto dendritic fibrous nanosilica (DFNS) for improved U(VI) adsorption.
• To enhance the stability and adsorption capacity of LDHs under acidic conditions through an interface-constrained strategy.

Main Methods:

• An interface-constrained strategy was employed to anchor Mg-Co LDHs *in situ* within the pore channels of DFNS.
• The synthesized DFNS@Mg-Co LDH composite was characterized for its structural and adsorption properties.

Main Results:

• The DFNS@Mg-Co LDH composite exhibited a high U(VI) uptake capacity of 1143 mg g^-1 at pH 3.
• The composite demonstrated a 4.8-fold increase in U(VI) uptake compared to pristine DFNS, attributed to enhanced acid endurance and increased active sites.
• Excellent U(VI) removal was observed across various water conditions due to the material's selectivity and stability.

Conclusions:

• The interface-constrained strategy successfully enhanced the acid endurance and U(VI) adsorption capacity of Mg-Co LDHs.
• DFNS@Mg-Co LDH presents a promising and durable solution for uranium capture from diverse water sources, particularly in challenging acidic conditions.