Remediation of nitrate contaminated groundwater using a simulated PRB system with an La–CTAC–modified biochar filler

In the present study, Erigeron canadensis L., a typical invasive plant in Southwest China, was utilized as raw material to prepare original biochar (ECL), rare earth element La–modified (La–ECL), and La coupling cationic surfactant [cetyltrimethylammonium chloride (CTAC)]–modified (La/CTAC–ECL). These materials were then added simulated permeable reactive barriers (PRBs) their nitrate (NO 3 − ) contaminant remediation performances evaluated groundwater. The results show that breakthrough time for NO PRB column increases concentration of influent flow rate decreases, whereas with filler particle size height initially increases, decreases. Considering an initial 50 mg L −1 , range 0.8–1.2 mm, maximum adsorption capacity La/CTAC–ECL is 18.99 g 10 cm 15 ml min . quantity adsorbed 372.80 obtained using Thomas Yoon–Nelson models accurately predict groundwater under different conditions, are consistent those from dynamic experiments. TEM, XRD, FTIR, XPS analyses demonstrate modification CTAC improves surface structure, porosity, permeability, configuration functional groups biochar. mechanisms removal include pore filling, adsorption, ion exchange, electrostatic adsorption. composite exhibits superior potential contaminated