Rational design of the nanocomposite by in-situ sub-10 nm La(OH)3 formation for selective phosphorus removal in waters

Abstract

Phosphate removal by nanocomposite is a promising approach in water remediation. But it is still challenged by the small size nanoparticles formation and kinetic diffusion under the nanopore confinement. Herein, we report a different strategy, which relies on the deposition of nano-La(OH)3 particles inside the porous biomass Artemia Cyst-shells matrix. The charged amino acid components of matrix drivers for the in-situ growth of rod-like nano-La(OH)3 with size below 10 nm, while the broad-porous skeleton structures enable and accelerate the accessibility of trace phosphate to nano-La(OH)3 sorption sites available, resulting in the efficient and fast phosphate removal performance. This nanocomposite exhibited excellent adsorption capacity as high as 180.5 mg/g, which is beyond of most adsorbents by recent-ten-year survey. It also revealed superior selectivity against various competing ions with a distribution coefficient (Kd) up to ∼ 34000 mL/g, exceeding commercial ion-exchange resin by 15 times and outdoing 10 times the performance of well-known Fe based nanocomposites Lewatit FO36. An outstanding treatment capacity of 10980 L/kg under the continuous operation and the satisfactory regeneration property (> 95 %) further proves its applicability. This technology provides a new perspective approach for nanocomposite design and wastewater determination. It is also promising alleviating problems of trace phosphate deep purification in drinking water and wastewater medium.