This technology develops a graphene/layered double hydroxide (LDH) composite material with highly selective phosphate adsorption capability and excellent desorption performance. By controlling the applied voltage, phosphate can be electrically desorbed and recovered, enabling rapid, effective, and low-energy removal and recovery of phosphate from electroplating wastewater, with an adsorption capacity of up to 244.1 mg-PO₄ g⁻¹. Moreover, the electrode material can be regenerated and reused.

We have developed a graphene/LDH composite material with highly selective phosphate adsorption capability, featuring the following innovations:
  
  1. Unique ion-exchange behavior enables efficient phosphate recovery. 
  
  2. Calcination-driven regeneration allows the material to be restored and reused. 
  
  3. Valence-state tuning of metal oxides increases charge density, thereby enhancing phosphate selectivity. 
  
  4. Smart electro-regulation enables controllable phosphate adsorption and release.

To ensure a stable supply of phosphorus resources, the government will enforce phosphate discharge limits. A recent survey indicates that 352 companies in science parks exceed the regulatory threshold. In response, we have developed a 10 L-scale prototype system, with a collaborative MoU with AUO to leverage patent-protected electrodes integrated with a CDI module. We will further develop a 500 L-scale on-site pilot unit for practical validation, operation, and testing at AUO wastewater plant.