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This study presents the synthesis of a novel composite catalyst, ZIF-67, doped on sodium bicarbonate-modified biochar derived from kumquat peels (ZIF-67@KSB3), for the enhanced activation of peracetic acid (PAA) in the degradation of acetaminophen (APAP) in aqueous solutions. The composite demonstrated a high degradation efficiency, achieving 94.3% elimination of APAP at an optimal condition of 200 mg L−1 catalyst dosage and 0.4 mM PAA concentration at pH 7. The degradation mechanism was elucidated, revealing that superoxide anion (O 2 •−) played a dominant role, while singlet oxygen (1O 2) and alkoxyl radicals (R–O•) also contributed significantly. The degradation pathways of APAP were proposed based on LC-MS analyses and molecular electrostatic potential calculations, identifying three primary routes of transformation. Stability tests confirmed that the ZIF-67@KSB3 catalyst retained an 86% efficiency in APAP removal after five successive cycles, underscoring its durability and potential for application in pharmaceutical wastewater treatment. [Display omitted] • ZIF-67 loaded on kumquat peel-derived biochar actived peracetic acid effectively. • Acetaminophen (APAP) degradation efficiency exceeeded 90% across various pH. • The composite promoted O 2.•−, 1O 2 , R–O•, and HO• generation in APAP degradation. • The composite showed high environmental safety and recycling effectiveness. [ABSTRACT FROM AUTHOR]

[Display omitted] • NiCo 2 O 4 and biochar composite was used for PMS activation to degrade TC. • The combination could synergistically enhanced the PMS activation for TC degradation. • The composite possessed excellent durability. • Radical and non-radical activation occurred for TC degradation. In this study, biochar produced from sunflower seeds husk was activated through ZnCl 2 to support the NiCo 2 O 4 nanoparticles (NiCo 2 O 4 @ZSF) in catalytic activation of peroxymonosulfate (PMS) toward tetracycline (TC) removal from aqueous solution. The good dispersion of NiCo 2 O 4 NPs on the ZSF surface provided sufficient active sites and abundant functional groups for the adsorption and catalytic reaction. The NiCo 2 O 4 @ZSF activating PMS showed high removal efficiency up to 99% after 30 min under optimal condition ([NiCo 2 O 4 @ZSF] = 25 mg L-1, [PMS] = 0.04 mM, [TC] = 0.02 mM and pH = 7). The catalyst also exhibited good adsorption performance with a maximum adsorption capacity of 322.58 mg g−1. Sulfate radicals (SO 4 •−), superoxide radical (O 2 •−), and singlet oxygen (1O 2) played a decisive role in the NiCo 2 O 4 @ZSF/PMS system. In conclusion, our research elucidated the production of highly efficient carbon-based catalysts for environmental remediation, and also emphasized the potential application of NiCo 2 O 4 doped biochar. [ABSTRACT FROM AUTHOR]

[Display omitted] • Hydrothermal treatment created good precursor for production of biochar. • Pore formation and enlarged surface area of biochar were obtained with ZnCl 2. • The biochar showed superior tetracycline adsorption capacity (673.0 mg·g−1). In this study, sunflower seed husk biochar prepared by ZnCl 2 -activated and hydrothermal carbonization (HZSF) was studied for its effectiveness in removing tetracycline (TC) from an aqueous solution. The physical and chemical properties of materials were characterized by different methods of surface analysis. The specific surface area of HZSF is significantly enhanced over 1200 times compared with non-modified biochar (HZSF: 1578.3 m2·g−1, SF-700: 1.3 m2·g−1), which has an enhancement effect on the TC adsorption capacity. The HZSF showed that the Langmuir isotherm and pseudo-second-order kinetic models could properly characterize the adsorption processes. In the Langmuir isotherm model, HZSF exhibited effective adsorption performance with q max of 673.0 mg·g−1 at 298 K for 24 h. The possible mechanisms for the adsorption process were the monolayer, chemical adsorption, and the participation of strong intermolecular forces. In general, HZSF has the potential to be a useful adsorbent for the elimination of antibiotics from water-based solutions. [ABSTRACT FROM AUTHOR]

[Display omitted] • Biochar (PSF) was synthesized by pyrolysis of H 3 PO 4 -treated sunflower seeds husk. • The PSF exhibited higher adsorption performance compared to untreated biochar. • Antibiotics (TC, CIP, SMX, and IBP) were effectively adsorbed by the PSF. • Multiple mechanisms governed the adsorption mechanism of antibiotics onto PSF. In recent years, the unnecessary overuse of antibiotics has increased globally, resulting in antibiotic contamination of water, which has become a significant environmental concern. This study aims to examine the adsorption behavior of antibiotics (Tetracycline TC, Ciprofloxacin CIP, Ibuprofen IBP, and Sulfamethoxazole SMX) onto H 3 PO 4 -activated sunflower seed husk biochar (PSF). The results demonstrated that H 3 PO 4 could enhance the specific surface area (378.8 m2/g) and create a mesoporous structure of biochar. The adsorption mechanism was investigated using kinetic models, isotherms, and thermodynamics. The maximum adsorption capacities (q max) of TC, CIP, SMX, and IBP are 429.3, 361.6, 251.3, and 251.1 mg g−1, respectively. The adsorption mechanism of antibiotics on PSF was governed by complex mechanisms, including chemisorption, external diffusion, and intraparticle diffusion. This research provides an environmentally friendly method for utilizing one of the agricultural wastes for the removal of a variety of antibiotics from the aquatic environment. [ABSTRACT FROM AUTHOR]