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[Display omitted] • This is the first review on the application of modified hollow glass microspheres as adsorbents in wastewater treatment. • The modification of adsorbent by various functional groups and the potential mechanisms for pollutant removal are reviewed. • The regeneration performance of self-floating adsorbents is reviewed. • The adsorption performance and related influencing factors of self-floating adsorbents are summarized. The adsorption method is widely used in wastewater treatment because of its advantages of simple operation, high efficiency, no secondary pollution, and reusability. In the process of adsorption, the recovery of adsorbents determines their economic feasibility and suitability for large-scale practical applications, so it is of great significance to develop new functional adsorbents with self-floating separation characteristics to replace traditional adsorbents. Hollow glass microsphere (HGM) is a kind of hollow closed sphere, which has the advantages of low density, stable chemical properties, reusable, excellent compression resistance, etc. Due to the unique structure and chemical properties of HGM, it has extremely high potential value in the field of wastewater treatment, and is an ideal carrier for preparing adsorbents with self-floating adsorbents. In this paper, the modification of HGM, the regeneration of adsorbents, the factors affecting the adsorption performance and challenges are reviewed. It is found that most of the existing modification methods of HGM are surface chemical modification, and the adsorption effect and regeneration are significant, but the adsorption effect is greatly affected by the change of pH. This review aims to provide a theoretical basis for the application of HGM in wastewater treatment, and for relevant researchers to develop adsorbent with HGM as the main body, clarify ideas, and explore the potential of developing HGM into practice for large-scale wastewater treatment. [ABSTRACT FROM AUTHOR]

Despite the rapid advances in treatment technologies for per-fluoroalkyl and poly-fluoroalkyl substances (PFAS) removal, the efficiency and practicality of these technologies would be either questionable or not cost-competitive sometimes. Several studies have successfully removed or destroyed PFAS from aqueous solutions but only to a limited level. Nevertheless, the treatment technologies are still evolving, and thus, long-term strategies should be implemented with caution. In this study, the physical and chemical properties of PFAS were provided. The emerging treatment technologies for PFAS removal, such as ion exchange resins, adsorption, advanced oxidation process, and membrane-based separation, are briefly reviewed in this paper. The treatment's mechanisms and future research trends are covered to provide insight into the technologies above. The study covered the treatment technologies for PFAS removal systematically and hierarchically and delivered a guideline for creating efficient and robust treatment technology for PFAS treatment. [Display omitted] • Ion exchange Resins is more efficient than adsorption processes for short-chain PFAS removal. • Zwitterionic PFASs received lower attention than anionic, cationic, and non-ionic PFASs. • Integrating treatment technologies would be a viable option for a sustainable solution. • Membrane rejection to PFOS increases with increasing the ionic solution of feed solution. [ABSTRACT FROM AUTHOR]

Layered double hydroxides (LDHs) are often used as adsorbents and catalysts in pollutant treatment because of their unique layered structure and chemical properties. The control of gaseous pollutants is an important step in environmental pollution control. In this paper, the research status of LDHs in the capture and transformation of typical gaseous pollutants (SO 2 , NO x , VOCs, CO 2) is reviewed, especially the purification mechanism and application advantages of these materials are expounded, and the future development direction of this material is predicted and analyzed. [Display omitted] [ABSTRACT FROM AUTHOR]

Cellulose-based materials are a sustainable alternative to polymers derived from petroleum. Cellulose nanocrystal (CNC) is a biopolymer belonging to this family; it is commonly known for its important physical and chemical properties and ability to form a film. Modifying CNC via electrostatic interaction provided by cationic polymers is a facile and promising technique to enlarge the application of CNC. Herein, we report the preparation of films, from blends of negatively charged CNC and positively charged poly (trimethyl aminoethyl methacrylate) (PTMAEMA). The interaction between CNC and PTMAEMA was verified by using a quartz crystal microbalance with dissipation monitoring (QCM-D), as well as by measuring the particle size and ζ-potential of the casting mixture. To favor the application of the nanocomposite film in water treatment, the film was supported on Whatman™ paper, and adsorption tests were conducted using perfluorooctanoic acid (PFOA) as a model compound for the family of persistent fluorinated pollutants known as PFAS (per - and polyfluoroalkyl substances). [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • FPFMs are based on the conjunction of both γ-Fe 2 O 3 and PDA onto fungal mycelia. • FPFMs fabricated via immobilization exhibit excellent Th(IV) adsorption performance. • The chelation, coordination and ion-exchange play an important role in adsorption. • FPFMs could be used for repairing multiple types of nuclide-polluted aqueous system. Abstract In this paper, a facile immobilization method was applied to load alginate, ferric oxide and dopamine onto fungal mycelium to prepare a series of spherical composites as potential adsorbents for the separation and removal of thorium from aqueous solution. The structure and chemical properties of the as-prepared adsorbents were characterized in detail via scanning electron microscopy-energy-dispersive X-ray spectroscopy (SEM-EDX), Fourier transform infrared spectrometry (FT-IR), X-ray photoelectron spectroscopy (XPS), pH value at the point of zero charge (pH PZC) and thermogravimetric (TG) analysis. Based on the adsorption studies, the magnetic gamma-ferric oxide (γ-Fe 2 O 3) and polydopamine (PDA) cofunctionalized fungal microspheres (FPFMs) exhibited excellent adsorption performance for thorium and could represent convenient agents for the removal and recovery of thorium. The equilibrium adsorption data for the FPFMs were well fitted by the Langmuir model, and a high maximum thorium adsorption capacity of 326.346 mg·g−1 was obtained. The thermodynamic parameter values (Δ H 0 > 0, Δ S 0 > 0, Δ G 0 < 0) demonstrated that the thorium adsorption process was feasible, endothermic and spontaneous in nature. This work indicated that FPFMs have great potential to be employed as effective adsorbents for practical industrial water pollution treatment. Importantly, the possible mechanism of thorium adsorption on the homogeneous surface of FPFMs represented a combination of chelation interactions, coordination and ion exchange. [ABSTRACT FROM AUTHOR]

Unique electrical properties and chemical modifiability make fullerenes convenient for the fabrication of various measurement devices. In this paper, the fullerene derivative, C 60 -Lys, with abundant –OH,-NH 2 , and -COONa, has been creatively used to obtain a humidity sensor with high response (ΔI/I ≈ 2000) and low hysteresis (ΔH≈2.9% RH). The response time and recovery time of the C 60 -Lys sensor reach 24s and 29s respectively in the range of 11–97% relative humidity (RH). Hydrogen bonding and van der Waals forces between fullerene derivatives and water molecules play an important role in the adsorption and desorption of water molecules while the formation of ions causes rapid changes in the impedance of the C 60 -Lys sensor. It is worth noting that the device has excellent reproducibility and stability. These indicate it is a very good strategy to synthesize new humidity sensing materials by modifying groups on fullerenes to change the hydrophilicity of the surface. • A fullerene derivative, C 60 -Lys, has been applied tothe humidity sensor. • The C 60 -Lys sensor has a rapid response, less hysteresis, and good non-contact response performance. [ABSTRACT FROM AUTHOR]

The activated carbon has been extensively studied for various applications especially the wastewater treatment. In this paper, we reported a new two-step method for the green preparation of the novel mesoporous carbon that relied on the synthesis of adsorbents by hydrothermal method and the surface modification by freeze-drying process. The freeze-dried carbon microsphere (FCMS) was then studied by a series of characterization techniques to elucidate their physico chemical properties. Batch experiments were conducted to evaluate the adsorption behaviors for the removal of rhodamine B (RhB) and methylene blue (MB) with contact time, pH, and initial concentration from the wastewater. The results demonstrated that the organic dyes RhB and MB could be rapidly adsorbed on FCMS within 20 min without any assistance and exhibited excellent adsorption capacity (170.461 and 216.606 mg g−1) toward RhB and MB. In addition, the results of adsorption/desorption cycle showed that the retention rate of adsorption capacity for MB and RhB can reach 77.7 % and 85.2 %, respectively. Finally, it can be concluded that FCMS should be an efficient and promising candidate for the removal of organic pollutants from wastewater. [Display omitted] [ABSTRACT FROM AUTHOR]

In this paper, computer simulation was used to assist in the rapid preparation of Myclobutanil (MYC) molecularly imprinted nanoparticles (MYC-MINs), which involved screening the best functional monomers and solvents, determining the optimal polymerization ratio, and estimating the MYC-2-(Trifluoromethyl)acrylic acid (MYC-TFMAA) self-assembly process and its infrared spectrum. Thermodynamic analysis showed that MYC-TFMAA self-assembly was an endothermic non-spontaneous process, and the pre-polymerization temperature was planned to be 30 °C. The MYC-MINs, prepared by solution polymerization, had a uniform particle size (the average diameter of 134.26 nm, pore volume of 2.45 mL/g, specific surface area of 143.26 m2/g, and porosity of 78.27%). The polymer got to its dynamic adsorption equilibrium in 90min, and the saturated adsorption capacity was 4.78 mg/g. Repeated adsorption experiments proved that the MYC-MINs had stable physical and chemical properties, and a high specific adsorption capacity for MYC and its structural analogs as well. The separation imprinting factors of the polymer for MYC could reach to 2.31, and it was used as a filler in the solid phase extraction tube to purify the tobacco samples spiked with six triazole fungicide, and finally the extracts were analyzed by UHPLC-MS/MS. The average recovery range of spiked tobacco samples were 77.86%–100.52%, and relative standard deviation was 1.90%–10.60% (n = 3), which realized simultaneous detection of multiple triazole fungicides in tobacco. Image 1 • The Myclobutanil Molecularly Imprinted Nanoparticles was simulated by Gaussian. • The MYC-MINs had good adsorption recovery rates for four triazole fungicides. • The MYC-MINs had stable physicochemical properties and could be recycled 5 times. • The MYC-MINs SPE-UHPLC-MS/MS could simultaneously detect multi-triazole residues. [ABSTRACT FROM AUTHOR]

• Novel sodium alginate-based gel spheres were prepared by droplet polymerization. • The prepared GA (SA-Al/Ca) gel sphere showed good adsorption performance for S-OFX. • The adsorption equilibrium of two prepared gel spheres could be reached in 10 min. • The stabilities could be greatly improved by ion and covalent crosslinking. The extensive use of fluoroquinolones antibiotics (FQs) makes great contributions to human society, but it also brings serious threats due to its stable chemical properties and difficulty in natural degradation. Since FQs can form stable chelates with polyvalent metal cations, the new adsorbents based on this chelating agent can not only remove FQs effectively, but also have the characteristics of selective identification on target pollutants. In this paper, novel sodium alginate-based gel spheres were prepared by droplet polymerization with sodium alginate (SA) as functional monomer, AlCl 3 /CaCl 2 solutions and glutaraldehyde (GA) as crosslinking agents. The SA-Al/Ca gel spheres and GA (SA-Al/Ca) gel spheres were successively prepared for adsorption of levofloxacin (S-OFX) from aqueous solution. The results showed that after ion crosslinking with AlCl 3 /CaCl 2 solutions and covalent crosslinking with GA, the prepared SA-Al/Ca and GA (SA-Al/Ca) gel spheres showed high adsorption capacity and good reusability, respectively. The equilibrium adsorption capacity of SA-Al/Ca gel spheres reached up to 176.26 mg∙L−1 with the initial concentration of S-OFX as 100 mg∙L−1. The maximum removal rate of S-OFX was 92.10%. The GA (SA-Al/Ca) gel spheres had a certain degree of tolerance in temperature, pH, and ionic strength. The adsorption of S-OFX by both SA-Al/Ca and GA (SA-Al/Ca) gel spheres had fast kinetics. Moreover, the prepared GA (SA-Al/Ca) gel spheres also showed good reusability and stability. [ABSTRACT FROM AUTHOR]