Pb2+ removal performance by cotton-based and magnetic modified cotton-based biochar prepared from agricultural waste biomass
Yan-ling Zou, F. Z. Xu, Qiang Kong, Dawei Shang, Yujia Zhang, Wenhan Guo, Qian Wang, Congcong Zhao, Yuanda Du
Abstract
ABSTRACT This study aimed to investigate the Pb 2+ removal performance of cotton-based biochar (CB) and magnetic modified cotton-based biochar (MCB). The scanning electron microscopy revealed that MCB exhibiting a porous honeycomb structure with a specific surface area of 613.69 m 2 /g which bigger than that of CB (356.68 m 2 /g). The Fourier transform infrared spectrum analysis indicated the presence of metal oxides and hydroxides in MCB and the functional groups of O–H, C=O, and C≡C in both MCB and CB. The signal of Fe 3 O 4 and Fe 3 C was observed in X-ray diffraction analysis of MCB, which indicated the success of magnetic modification of MCB. The maximum monolayer adsorption capacities (Q m ) of MCB and CB on Pb 2+ were 208.33 and 156.25 mg/g, respectively. The adsorption kinetics of MCB and CB were both best fitted with the pseudo-second-order model (R 2 > 0.99), and the adsorption isotherms of the two biochar were well-described by the Langmuir adsorption model (R 2 > 0.99). The results of this study revealed the significant physicochemical difference of two biochar and indicated that magnetic modification can enhance the Pb 2+ adsorption capacity of biochar, suggesting that MCB is a potential adsorbent for wastewater treatment.