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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]

Highly efficient removal of bilirubin from blood by hemoperfusion for liver failure therapy remains a challenge in the clinical field due to the low adsorption capacity and slow adsorption kinetics of currently used bilirubin adsorbents (e.g., activated carbon and ion‐exchange resin). Recently, porous aromatic frameworks (PAFs) with high surface areas, tunable structures, and remarkable stability provide numerous possibilities to obtain satisfying adsorbents. Here, a cationic PAF with more mesopores, named iPAF‐6, is successfully constructed via a de novo synthetic strategy for bilirubin removal. The prepared iPAF‐6 exhibits a record‐high adsorption capacity of 1249 mg g−1 and can adsorb bilirubin from 150 mg L−1 to normal concentration in just 5 min. Moreover, iPAF‐6 shows a removal efficiency of 96% toward bilirubin in the presence of 50 g L−1 bovine serum albumin. It is demonstrated that positively charged aromatic frameworks and large pore size make a significant contribution to its excellent adsorption ability. More notably, iPAF‐6/polyethersulfone composite fibers or beads are fabricated for practical hemoperfusion adsorption, which also show better removal performance than commercial adsorbents. This work can offer a new possibility for designing PAF‐based bilirubin adsorbents with an appealing application prospect. [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]

[Display omitted] • A new magnetic composite of FSNCS/SDBS was synthesized at low temperature. • FSNCS/SDBS shows excellent adsorption performance for CIP. • FSNCS/SDBS shows wide pH adaptability. • SDBS enhances CIP's adsorption by improving the surface charge of FSNCS. In this study, a novel magnetic nickel cobalt sulfide/sodium dodecyl benzene sulfonate (FSNCS/SDBS) adsorbent was synthesized successfully by a facile protocol and was developed to remove ciprofloxacin (CIP) for water purification. The FSNCS/SDBS adsorbent is featured with excellent CIP adsorption capacity of 625 mg·g−1 (much higher than reported most adsorbents), wide pH adaptability (little changed CIP adsorption capacity in pH 6–11), and good magnetic property. The effects of pH and ionic strength on CIP adsorption were investigated. The calculative thermodynamic parameters indicated that CIP adsorption by FSNCS/SDBS was spontaneous and exothermic. CIP adsorption followed pseudo-second-order kinetics and an isotherm best fit with the Langmuir adsorption mode. The adsorption mechanism of CIP onto FSNCS/SDBS was proposed and demonstrated, which included the electrostatic interaction, π–π interaction, coordination with metal and hydrogen bonding. [ABSTRACT FROM AUTHOR]

With the rapidly increased discharges of various complex dyeing wastewaters, adsorbents are required to own more properties such as cost-effectiveness, amphoteric ability, and rapid solid-liquid separation ability, to treat dyeing wastewaters. A multi-functional adsorbent was synthesized by co-grafting m-phenylenediamine and sodium allyl sulfonate on the surface of a low-cost base-material: hollow glass microsphere (HGM). Characterization results indicated the surface roughness and –Si–OH groups of HGM were increased by NaOH corrosion; functional groups such as aromatic-rings, –NH 2 , and –HSO 3 − were grafted on the surface of HGM. The synthesized adsorbent showed amphoteric attraction abilities for anionic acid green 25 and cationic basic fuchsin dyes. Kinetics and isotherms studies suggested the PSO model and Langmuir model were most satisfactory for adsorption processes, the theoretical maximum adsorption capacities for acid green 25 and basic fuchsin reached 454.55 and 588.24 mg g−1, respectively. The mechanism investigations indicated the electrostatic attraction, π-π stacking, and hydrogen bonds were the potential interaction forces between dyes and adsorbents. The synthesized material owns self-floating ability due to the hollow structure of HGM, over 95.7% of adsorbents were collected at water surface via the self-floating process in 12 min, which was beneficial to the solid-liquid separation process and the reuse of adsorbents. The technologies developed by these research efforts can serve as templates for synthesizing multi-functional adsorbents for complex wastewaters decontaminations. [Display omitted] • First demonstration of an amphoteric self-floating adsorbent. • The adsorption capacities of anionic/cationic dyes reached 454.55/588.24 mg g−1. • Electrostatic force, π-π stacking, hydrogen bond were dominant adsorption mechanisms. • Over 95.7% of adsorbents were collected at the water surface within 12 min. • The multi-functional adsorbent is beneficial for cleaner production of dyeing goods. [ABSTRACT FROM AUTHOR]

• Multifunctional magnetic composite nanoparticles were facilely prepared. • The as-prepared FS@CS-PAA showed excellent adsorption capacities for cationic dyes. • FS@CS-PAA exhibited satisfactory removal rates for metal ions in a wide pH range. • The good adsorption ability was attributed to abundant active sites from CS-PAA. • FS@CS-PAA's good stability and reusability facilitated its practical application. Wastewater containing highly toxic, non-biodegradable and carcinogenic organic dyes and metal ions has been regarded as a severe threat to ecological environment and human health. Thus, it is of great significance to develop an effective approach to purify this kind of wastewater. Herein, novel magnetic adsorbent FS@CS-PAA was facilely prepared by coating anionic polyacrylamide-modified chitosan (CS-PAA) on the surface of silica-combined Fe 3 O 4 (FS). The morphology, structure, physic-chemical and magnetic properties of as-prepared FS@CS-PAA were fully characterized by various characterization techniques. Its adsorption behaviors towards cationic dyes and metal ions were systematically investigated in single systems, binary systems, and model wastewater. FS@CS-PAA was proved to have superior adsorption capacities of 2330.17 and 1044.06 mg g−1 respectively for crystal violet and methylene blue at 318.15 K, much higher than other reported adsorbents. Besides, FS@CS-PAA exhibited a pH-independent adsorption capability for metal ions, as demonstrated in single systems and in metal ion-dye binary systems, thus it could be used to treat a variety of metal ion wastewaters with different pH values. Moreover, FS@CS-PAA could be effectively and easily regenerated by HCl solution after the treatments of both synthetic wastewater and model wastewater. As revealed in FTIR and XPS analyses, the adsorption mechanism was mainly attributed to the electrostatic interaction, hydrogen bonding, cation exchange and chelating effect. With its excellent adsorption capacity for cationic dyes, pH-independent adsorption capability for metal ions, easy separation ability, satisfactory stability and good reusability, FS@CS-PAA can become an ideal candidate for wastewater treatment. [ABSTRACT FROM AUTHOR]

Wastewater containing dyes poses a severe threat to human health and to environmental safety. Hence, finding an effective way to treat this wastewater has attracted wide attentions. In this study, quaternary ammonium group-rich magnetic nanoparticles (MNPs), Fe 3 O 4 @SiO 2 -MPS-g-DAC (FSMD), were facilely prepared by grafting polymerization and served as a cationic adsorbent to remove anionic dye Orange G from aqueous solutions. Being compared with Fe 3 O 4 @SiO 2 -MPS MNPs, the adsorption capacity of FSMD MNPs was notably enhanced and it could be maintained in a high level under a wide solution pH range. The dependency on pH and the sensitivity to ionic strength indicated that the main adsorption mechanism was the electrostatic interaction. The adsorption kinetics followed the pseudo-second-order model, and the adsorption isotherms were well described with the Langmuir model. According to the thermodynamic analysis, the adsorption process was spontaneous and endothermic. FSMD MNPs were proved to have advantages of fast adsorption rate, high adsorption capacity, easy separation ability under external magnetic field, and satisfactory reusability, therefore they can be applied in the removal of anionic dyes from wastewater. [ABSTRACT FROM AUTHOR]