Efficient Adsorption of a Sulfonamide Antibiotic in Aqueous Solutions with N-doped Magnetic Biochar: Performance, Mechanism, and Reusability

Abstract

Conventional biochar has limited effectiveness in the adsorption of sulfonamide antibiotics, while modified biochar exhibits greater adsorption potential. Residues of sulfamethoxazole (SMX) in the aquatic environment can threaten the safety of microbial populations as well as humans. In this study, iron–nitrogen co-doped modified biochar (Fe-N-BC) was prepared from palm fibers and doped with Fe and urea via synthesis at 500 °C. Fe-N-BC has a richer surface functional group based on elemental content, X-ray photoelectron spectroscopy, X-ray diffraction, and Fourier transform infrared spectroscopy. The Brunauer–Emmett–Teller (BET) specific surface area test exhibited Fe-N-BC, which possessed a greater surface area (318.203 m2/g) and a better developed pore structure (0.149 cm3/g). The results of the hysteresis loop and the Raman spectrum show that Fe-N-BC has a higher degree of magnetization and graphitization. Fe-N-BC showed a remarkable adsorption capacity for SMX (42.9 mg/g), which could maintain 93.4% adsorption effect after four cycles, and 82.8% adsorption capacity in simulated piggery wastewater. The adsorption mechanism involves pore filling, surface complexation, electrostatic interactions, hydrogen bonding, and π–π EDA interactions. The results of this study show that Fe-N-BC prepared from palm fibers can be a stable, excellent adsorbent for SMX removal from wastewater and has promise in terms of practical applications.

Significant Differences in the Effects of Nitrogen Doping on Pristine Biochar and Graphene-like Biochar for the Adsorption of Tetracycline

“…Obviously, those results consistently demonstrated that the N-doping process significantly decreased the adsorption sphere of PBC but significantly increased the adsorption sphere of N-GBC. Similar results were also obtained in the study of Diao et al [39], which can be explained by the breaking down of carbon framework due to the gas produced by urea during pyrolysis [40].…”

Catalytic degradation of tetracycline hydrochloride using surface nitrogen-rich activated carbon based on polyaniline

“…All patterns display a strong D-band (∼1342 cm −1 ) and G-band (∼1595 cm −1 ), which generally represent the disorder or defects of the carbon structure and the graphitized structure, respectively. 27 The peak intensity ratio of the D band to G band ( I D / I G ) for 3.0PANI@AC900 (1.55) and 3.0PANI–AC900 (1.47) was higher than AC900 (1.03) and PANI900 (1.31), indicating that more defects were formed in the carbon structure due to the introduction of polyaniline precursors. 28 In particular, the maximum I D / I G value of 3.0PANI@AC900 demonstrates the lower degree of graphitization and the presence of more defects than 3.0PANI–AC900, which indicates that in situ nitrogen doping is better than physical blending nitrogen doping.…”

Biochar Derived from Palm Waste Supported Greenly Synthesized MnO2 Nanoparticles as a Novel Adsorbent for Wastewater Treatment

“…The nitrogen adsorption-desorption isotherm of the palm fronds, biochar, and MnO 2 /PF biochar is presented in Figure 4. This figure shows that the palm fronds and biochar possessed type II and IV isotherms with an H3 hysteresis loop [43], indicating the presence of macroporous and mesopores structures, while the MnO 2 /PF biochar adsorbent possessed a type IV isotherm with an H3 hysteresis loop, which is characteristic of a solid with a mesoporous structure [43]. On the other hand, the textural properties of the adsorbents are tabulated in Table 1.…”