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Dye effluent discharged into the environment can cause serious pollution and damage to the environment. It is crucial to develop adsorbents with excellent adsorption capacity and stable regeneration to meet practical application requirements for the treatment of dye-bearing wastewater. Herein, MoS2 nanoparticles were confined inside a cellulose aerogel to prepare a larger nanocomposite adsorbent (denoted as CAM) for efficient Congo Red (CR) removal from water. Chemical and morphological features of the CAM were examined using XPS, FTIR, XRD, SEM, and HRTEM, while CR adsorption on the nanocomposite was systematically investigated through batch experiments. The CR adsorption process was well described using the Langmuir model, with the maximum adsorption capacity calculated as 334.92 mg/g. The kinetic study illustrated that CR adsorption onto the CAM followed the pseudo-first-order model, and the dye diffusion process into the aerogel was the rate-limiting factor. The hybrid material exhibited excellent CR adsorption selectivity and maintained stable adsorption capacity even in the presence of a high concentration of competitive ions. Importantly, the hybrid aerogel was efficiently regenerated with ethanol and reused for dye adsorption in subsequent batches. Based on all of these results, CAM shows promise for the treatment of dye pollutants. [ABSTRACT FROM AUTHOR]

Excess phosphate in water can cause eutrophication, which must be addressed. Despite many efforts devoted to the adsorptive removal of phosphate from water, the development of new adsorbents with high adsorption capacity is highly desirable. Herein, a novel nanocomposite was proposed for phosphate removal by confining hydrated ferric oxide (HFO) nanoparticles into a cellulose aerogel (CA) network named as HFO@CA. Benefiting from the characteristics of the low density and porous structure of CA, the internal surface of the nanocomposite is more accessible and thus improves the utilization of the HFO nanoparticles. Batch adsorption experiments were carried out to evaluate the phosphate uptake by the prepared adsorbent. The maximum adsorption capacity of HFO@CA occurs at near-acidic pH. With increasing temperature, the composite adsorbent is more favorable for phosphate adsorption. Moreover, the hybrid aerogel exhibited fast kinetic behavior for phosphate removal, which could be accurately depicted by pseudo-second-order model. HFO@CA shows excellent adsorption selectivity in solutions containing competitive anions at higher levels. In addition, five cycles of the phosphate adsorption experiments without obvious capacity loss indicated that HFO@CA has great regenerability. These results demonstrate that HFO@CA has a wide field of application with good prospects in phosphate removal from wastewater, which also provides a new strategy to prepare adsorbents with excellent performance using renewable cellulose resources. [ABSTRACT FROM AUTHOR]

[Display omitted] • LDH nanosheets were confined to prepare a new millimeter-sized nanocomposite. • It exhibits high thermal, mechanical, and chemical stability. • It shows high adsorption capacity and preferable uptake toward phosphate. • The exhausted nanocomposite could be effectively regenerated and used repeatedly. • Satisfactory treatment volume and hydraulic characteristics were observed in fixed-bed. The efficient removal of phosphate from waters is critical to mitigating eutrophication. Recently, layered double hydroxides (LDHs) have been believed to be promising adsorbents for phosphate removal. Nevertheless, the scaled-up application of LDHs is limited by the difficulties of separation, excessive pressure drops, and potential metal leaching. In this study, a millimeter-sized nanocomposite, MgAl-201, was fabricated by impregnating Mg/Al LDH nanosheets into a polystyrene anion exchanger D201. The resulting MgAl-201 combines the inherent affinity of Mg/Al LDH toward phosphate and the excellent hydrodynamic performance of the support material. Benefiting from the shielding effect from the cross-linked polymeric host, MgAl-201 exhibits satisfactory chemical stability in the range of pH 3–11 with a negligible metal release. Adsorption experiments show that MgAl-201 has superb applicability to neutral phosphate-contaminated waters. It reaches adsorption equilibrium within 270 min, and the maximum adsorption capacity calculated by the double Langmuir model is 52.0 mg/g. Meanwhile, MgAl-201 exhibits more preferable adsorption toward phosphate than D201 when coexisting anions are at relatively high levels. FTIR and XPS surveys revealed that two distinct adsorption interactions were involved in phosphate removal, that is, electrostatic interactions from the quaternary ammonium groups bonded on the host and the interlayer exchangeable anions in the encapsulated Mg/Al LDH, and specific inner-sphere complexation from the −OH groups in the Mg/Al LDH layers. For wastewater application, a satisfactory treatable volume of 580 BV was achieved to reduce the effluents from 2.0 mg/L to 0.5 mg/L, which was up to 8 times that of the traditional anion exchanger D201. Furthermore, MgAl-201 could be easily regenerated using the Na 2 CO 3 -NaCl binary solution and maintained good reusability without significant capacity loss after 5 adsorption-desorption cycles. The results suggest that MgAl-201 is of great application capability for preferable phosphate sequestration in advanced wastewater treatment. [ABSTRACT FROM AUTHOR]

Phosphate removal plays a key role in alleviating the eutrophication of water bodies. Herein, a new bimetallic nanocomposite (La-Zr-D201) was prepared for enhanced phosphate removal by confining binary metal oxide (La-Zr) nanoparticles into the pores of a polymeric anion exchanger (D201). The encapsulated La-Zr oxides retain the specific sorption toward phosphate through ligand exchange. The host D201 provides satisfactory hydraulic properties and mechanical strength, and its macropores covalently bound positively charged ammonium groups could enhance nanoparticles dispersion and phosphate diffusion kinetics. Compared with the monometallic samples (La-D201, Zr-D201) and La-Zr loaded active carbon (La-Zr-AC), La-Zr-D201 possesses a higher adsorption capacity for its special structure and a stronger adsorption affinity toward phosphate. Phosphate removal on La-Zr-D201 was examined as a function of solution pH, reaction time, temperature, and competing anions, and the experiment results showed that the nanocomposite possessed superior phosphate adsorption capacity and selectivity. The underlying mechanism for the specific sorption and the stronger affinity of bimetallic adsorbents toward phosphate than monometallic ones were proved by XPS. Besides, column adsorption demonstrated 1350 BV of synthetic water (2 mg P-PO 4 3−/L) could be treated efficiently by La-Zr-D201, while only 160 BV for the host D201. The binary NaOH-NaCl solution could effectively regenerate the spent adsorbents for repeated use. As a result, La-Zr-D201 possesses great potential in the application of enhanced phosphate removal from wastewater. [ABSTRACT FROM AUTHOR]

A p‐type TiO2 with Ti vacancies (D‐TiO2) was synthesized by a facile solvothermal treatment, and Ag/TiO2 with different Ag loading amount was prepared through a photo‐reduction deposition method. The samples were characterized through scanning electron microscopy, transmission electron microscopy, X‐ray diffraction, and X‐ray photoelectron spectroscopy. The adsorption and photocatalytic characteristics of tetrabromobisphenol A (TBBPA) on D‐TiO2 and Ag/TiO2 were investigated. The adsorption of TBBPA on Ag/TiO2 was significantly enhanced and was five times greater than that of pure TiO2. The increase in pH significantly inhibited the adsorption of TBBPA. The 2%‐Ag/TiO2 nearly completely degraded TBBPA in 10 min under UV–Vis light (λ > 360 nm), and the apparent reaction rate constant (kapp) reached 0.63 min−1. The significantly enhanced UV–Vis light catalytic properties of the Ag/TiO2 in comparison with that of TiO2 were attributed to the increased adsorption capacity and electron transfer ability of the Ag/TiO2. Free radical trap experiments results showed that holes and superoxide radicals play a major role in the catalytic degradation of TBBPA by Ag/TiO2. Moreover, the Ag/TiO2 catalyst exhibits high stability during TBBPA degradation even after three cycles. Practitioner points: Ti‐defected TiO2 and Ag/TiO2 were synthesized using a solvothermal and photo‐reduction deposition, respectively.Ag/TiO2 exhibited outstanding adsorption and photocatalytic activity for TBBPA removal under UV–Vis light.Holes and superoxide radicals play a major role in the photocatalytic degradation of TBBPA. [ABSTRACT FROM AUTHOR]

[Display omitted] • PDA-mediated MoS 2 nanocomposite with enhanced stability and Pb(II) removal performance was prepared. • It showed fast adsorption kinetics, excellent adsorption capacity and selectivity to Pb(II). • Pb(II) adsorption attributing to the synergistic effect of the host and MoS 2 nanoparticle. • A considerable working capacity was observed in fixed-bed column tests. • It can be used repeatedly without significant capacity loss. The engineering of macroscopic architectures by loading MoS 2 nanosheets onto larger framework materials is an efficient strategy to overcome the limitations preventing the application of nanosized MoS 2 -based adsorbents for Pb(II) removal. However, the large-scale utilization of these nanocomposites still faces several challenges as a result of their poor stability, slow adsorption kinetics, and low MoS 2 utilization. Herein, a practical and efficient nanocomposite (MoS 2 /PDA/MPS) was prepared by coating MoS 2 nanoflowers onto micron-sized polystyrene beads (MPS) via the construction of a strong adhesive polydopamine (PDA) interlayer. The PDA interface can adhere to the MPS surface and immobilize the MoS 2 nanopartices, thus facilitating the application of MoS 2 /PDA/MPS in flow-through systems. Further, the flower-like structure of the MoS 2 on the outer surface of the host exposes active sites and facilitates mass transfer compared to those of traditional nanocomposites. Meanwhile, the R-SO 3 - groups of MPS can enhance permeation and preconcentrate the Pb(II) ions via the Donnan membrane effect, resulting in improved adsorption kinetics and capacity. Batch adsorption experiments revealed that MoS 2 /PDA/MPS shows fast adsorption kinetics (<45 min), exceptional adsorption capacity (371.7 mg/g, calculated from the Langmuir model at 298 K), and high adsorption selectivity for Pb(II) uptake. The excellent stabilities and reusability of the nanocomposite were tested over 10 adsorption–desorption cycles. In addition, a considerable working capacity (approximately 2000 BV) in synthetic wastewater was observed in fixed-bed column tests, and the used adsorbent could be readily regenerated with a binary NaCl–EDTANa 2 solution for reuse without significant capacity loss. Thus, MoS 2 /PDA/MPS has great applications for the remediation of lead-containing wastewater, and our findings provide new insights into the preparation of efficient MoS 2 -based adsorbents having practical applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel 3D nanocomposite was prepared by the simple mixing method. • It confines MoS 2 in the network with large‐sized and porous characteristics. • It exhibits high selective and efficient lead(II) removal from water. • Fixed-bed column exhibits superior applicability in the flow-system. • It could be effectively regenerated for sustainably utilized. The development of highly efficient and practical adsorbents for selective lead(II) capture remains an urgent challenge to be overcome. Herein, a new nanocomposite (W-MoS 2 @CA) was prepared by confining MoS 2 nanosheets with widened interlayer spacing in the cross-linked cellulose aerogels. W-MoS 2 @CA combines the excellent handling, flow characteristics, and porous structure of aerogels with the specific affinity and accessible interior spaces of MoS 2 toward lead cation. The adsorbent shows outstanding adsorption capacity and fast kinetics for lead removal. Benefiting from the high affinity between MoS 2 and lead, W-MoS 2 @CA exhibits excellent adsorption selectivity even in the solution containing multiple coexisting heavy metal ions and high concentrations of competing mineral cations. The centimeter/millimeter-sized of the 3D cellulose mesh skeleton significantly improves the hydraulics property of nanocomposite, enabling it to be conveniently used in the flow system. The considerable treatment volume in fixed-bed indicated that W-MoS 2 @CA is of great potential for lead removal in practice. In addition, W-MoS 2 @CA can be readily regenerated with negligible adsorption capacity loss after 5 adsorption − desorption cycles. These results confirm that W-MoS 2 @CA has a great prospect in the water remediation of lead-removing, and this work may provide a new avenue for the application of MoS 2 as an effective adsorbent in practical water/wastewater treatment. [ABSTRACT FROM AUTHOR]