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[Display omitted] • A novel magnetic NaCe(CO 3) 2 /Fe 3 O 4 (NCF) nanocomposite was synthesized easily. • NCF shows excellent adsorption performance (qm = 86.69 mg P g−1) for phosphate. • NCF shows exceptional selectivity for phosphate. • Effective and rapid uptake in low concentrations of phosphate. Phosphorus (P) contamination has become a worldwide issue due to its adverse impacts on water security and human health. Additional research is required because the selectivity and adsorption capacity of P adsorbents continue to impede their practical application. Herein, a novel NaCe(CO 3) 2 /Fe 3 O 4 nanocomposite (NCF) with good magnetic properties were synthesized through a modified hydrothermal method for P removal from water. With an adsorption capacity of 86.69 mg P g−1, the NCF demonstrates outstanding phosphate uptake efficiency. At low P concentrations, the removal rate exceeded 90.0%, and the residual P concentration was below 0.1 mg P L−1. Notably, NCF demonstrated exceptional P selectivity in actual water containing multiple substances, with negligible interference from competing ions and humic acid (HA). The adsorption processes of NCF were well described by the pseudo-second-order kinetic model (PSO) and Langmuir isotherm model, corresponding to its kinetics and thermodynamics, respectively. The exhausted NCF can be regenerated and retain an effective phosphorus removal capability even after regeneration. Characterization results demonstrated that electrostatic attraction and ligand exchange were responsible for P adsorption, forming stable CePO 4 crystals with low solubility. Moreover, the NCF demonstrated some efficacy in removing typical organic and inorganic phosphorus. [ABSTRACT FROM AUTHOR]

[Display omitted] • Calcite-biochar was prepared through a facile pyrolysis process from biomass waste. • CAB displayed excellent removal capacities for Cu(II) and CIP. • The adsorption-flocculation were involved in the removal of CIP. • Concentrations of Cu(II) had different effects on CIP removal. • The co-removal of Cu(II) and CIP included various interactions. The discharge of metals and antibiotics pose a serious risk to public health and environment. Gaining insight into the removal process is an imperative implication for comprehending environmental transformation of contaminants. In this study, a low-cost calcite-biochar (CAB) composite was prepared through a facial pyrolyzed process from shell waste for the removal of Cu(II) and ciprofloxacin (CIP) in single and mixed systems. CAB exhibited superior removal performance toward these two pollutants. In single system, CIP removal was adsorption coupled with flocculation and Cu(II) removal was adsorption combined with precipitation. The CIP removal followed the PSO kinetic and Freundlich isotherm model, while Cu(II) removal were better described by PSO kinetic and Langmuir isotherm model. In binary system, Cu(II) had an promotional and inhibitory effect on the removal of CIP, which depended on the concentration of Cu(II). But the adsorption capacity of Cu(II) removal was reduced with the existence of CIP. The microstructure analysis indicated that the cation bridging, hydrogen bonding, surface complexation and π-π interaction were attributed to the CIP removal and Cu(II) could act as a bridge or competitor. While the Cu(II) removal was inhibited by competing with the active sites or suppressing the formation of posnjakite in the coexistence of CIP. These results provided valuable information for the co-removal of CIP and heavy metal. [ABSTRACT FROM AUTHOR]

• MOFs are incorporated in chitosan beads uniformly and stably. • The MOFs are synthesized from metal hydroxide(or metal oxide) in situ. • The MOF loading can be controlled by changing the metal amount in the precursor. • ZIF-8-chitosan beads exhibit the adsorption capacity of 495.04 mg/g for tetracycline. • The beads can treat ~887 bed volumes of tetracycline solution in real water sample. Metal-organic frameworks (MOFs) have been attractive adsorbents for the treatment of antibiotic wastewater. However, in their powder form, the adsorbents suffer from the disadvantage of poor recyclability and complex operational process. Herein, we incorporated typical MOFs (ZIF-8, ZIF-67, HKUST-1, and Fe-BTC) into low-cost chitosan matrix for the tetracycline removal. Metal hydroxide(or metal oxide)/chitosan composite beads from the metal salt/chitosan solution were used as MOF precursor, which lead to the uniform and stable MOF loading into chitosan. This composition could not only shape MOFs into beads but also improve the adsorption capacity of the chitosan. As a result, ZIF-8-chitosan composite beads exhibited good adsorption performance toward antibiotic tetracycline. The adsorption processes followed pseudo-second-order model and Langmuir isotherm model. The maximum adsorption capacity could reach 495.04 mg/g, which is higher than most of the MOF-based or natural polymer-based tetracycline adsorbents. Moreover, the removal efficiency of ZIF-8-chitosan composite beads toward tetracycline was still above 90% after ten adsorption-desorption cycles. In the fixed-bed experiment, ZIF-8-chitosan column could treat ~887 bed volumes (BV) of tetracycline solution in real water sample. Both experimental characterizations and DFT calculations indicated that the adsorption mechanism involves in the electrostatic interaction, π-π stacking interaction and hydrogen-bonding interaction. This study provides a promising strategy for uniform MOF loading into the matrix and potential adsorbents for pharmaceutical wastewater treatment. [ABSTRACT FROM AUTHOR]