Biochar supported Fe-Cu bimetal composites prepared with waste materials for removal of tetrachloropicolinic acid from high salinity wastewater

In this work, we used coffee ground, iron ore and copper salts as raw materials to prepare Fe0 and Cu0 bimetal nanoparticles loaded biochar composites (CG\Fe-Cu). The composite can efficiently remove refractory tetrachloropicolinic acid (TCPA) from high saline organic wastewater (HSOW) due to the dual role of direct reduction by Fe-Cu bimetals and oxidation by in-situ generated reactive oxygen species. Nearly 95% of TCPA (10 mg L−1) was eliminated by 10 g L−1 of CG\Fe-Cu within 6 h in a NaCl solution of 3 g L−1, suggesting the good application potential in treatment of HSOW.