Adsorption removal and reuse of phosphate from wastewater using a novel adsorbent of lanthanum-modified platanus biochar

In this study, a novel adsorbent of lanthanum-modified platanus ball fiber biochar (La-TC) was developed for efficient adsorption and reuse of phosphate from actual wastewater. La-TC adsorbing phosphate could be used as agricultural fertilizer. The saturated adsorption capacity of phosphate on La-TC was 148.11 mg/g at dosage of 0.4 g/L, initial solution pH of 6.0, contact time of 20 min, and temperature of 35 degrees C, which was much higher than most phosphate biochar adsorbents. Simultaneously, La-TC had a wide pH (3-9) adsorption stability, a strong ability to resist interference of anti-competitive anion (SO42- and NO3-), and an outstanding regeneration ability. Fourier transform infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopy (XPS) were used to reveal the adsorption mechanism of La-TC to phosphate, including electrostatic adsorption, ligand exchange, and complexation mechanisms. In the fixed bed column experiment of phosphorus removal from real wastewater, the maximum treated bed volume was 420, 440 and 480 (BV) under the bed flow of 1 mL/min and La-TC of 0.5, 0.75 and 1.0 g, respectively. Outcomes suggested that La-TC had a broad prospect of engineering application for removal and reuse of phosphate from wastewater, also realizing the resource utilization of wasted platanus ball. (C) 2020 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.