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Abstract: Batch sorption experiments were conducted using macroreticular poly(vinyl alcohol) (MR-PVA) beads as a adsorbent to adsorb Pb(II) from both single component system and multi-metal solution in which experimental parameters were studied including solution pH, contact time, adsorbent dose, initial concentration of metal ions and ionic strength. The equilibrium isotherms were determined at pH 6 under constant ionic strength and at different temperatures. The results showed that the maximum adsorption capacity of Pb(II) (213.98mgg−1) with 1gL−1 of adsorbent was observed at 300mgL−1 at an initial pH value of 6.0 under temperature of 288K. Removals of about 60% occurred in 30min, and equilibrium was attained at around 150min. The equilibrium data for the adsorption of Pb(II) on MR-PVA beads was tested with various adsorption isotherm models among which three models were found to be suitable for the Pb(II) adsorption. In addition, the kinetic adsorption fitted well to the pseudo-second-order model and the corresponding rate constants were obtained. Thermodynamic aspects of the adsorption process were also investigated. [Copyright &y& Elsevier]

Radioactive nuclides and highly toxic organophosphates are typical deadly threats. Materials with the function of radioactive substances adsorption and organophosphates degradation provide double protection. Herein, dual-functional polyamide (PA)/polyethyleneimine (PEI)@Zr-MOF fiber composite membranes, fabricated by in-situ solvothermal growth of Zr-MOF on PA/PEI electrospun fiber membranes, are designed for protection against two typical model compounds of iodine and dimethyl 4-nitrophenyl phosphate (DMNP). Benefiting from the unique core-sheath structure composed of inner nitrogen-rich fibers and outer porous Zr-MOF, the composite membranes rapidly enrich iodine through abundant active sites of the outer sheath and form complexes with the amine of inner PEI, exhibiting a highly competitive adsorption capacity of 609 mg g -1 . Moreover, it can adsorb and degrade DMNP with the synergy of PEI component and Zr-MOF, achieving an 80 % removal of DMNP within 7 min without any additional co-catalyst. This work provides a feasible strategy to fabricate dual-functional materials that protect against radioactive and organophosphorus contaminants., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Dongzhi Yang reports financial support was provided by Beijing Municipal Science and Technology Commission. Dongzhi Yang reports financial support was provided by National Natural Science Foundation of China. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

This work illustrates a simple polymer thermal treatment strategy to develop high-dispersed Fe 2 O 3 /Fe nanoparticles residing in honeycomb-like N-doped graphitic carbon (Fe 2 O 3 /Fe@N-GC). The as-prepared Fe 2 O 3 /Fe@N-GC composites consist of three-dimensional (3D) strutted interconnective graphitic carbon frame, which would not only refrain from restacking and facilitate the charge transfer, but also provide more reaction interface between gas molecules and materials. Benefiting from the synergistic merits of Fe 2 O 3 /Fe, N-doping graphitic carbon, high surface area and unique 3D architectures, the optimal Fe 2 O 3 /Fe@N-GC presents impressive sensitivity and selectivity for NO 2 gas detection at room temperature with the response of 25.48-100 ppm, response time of 2.13 s, recovery time of 11.73 s, detection limit of 10 ppb and as long as 60 days of stability. As a result, the present Fe 2 O 3 /Fe@N-GC composite with an easy fabrication method and high sensitivity, selectivity, stabitliy towards NO 2 at RT would inspire various designs based on the 3D honeycomb structure for more real applications in gas sensors., (Copyright © 2020 Elsevier B.V. All rights reserved.)

In this study, a novel TiO 2-x /rGO-PS-Vis process was developed, which utilizes the TiO 2-x /rGO (Ti 3+ and oxygen vacancies self-doped TiO 2 coupled with reduced graphene oxide) nanocomposite as a promising and efficient activator of persulfate (PS) for the enhanced oxidation of micropollutants under visible -light irradiation. TiO 2-x /rGO exhibited a significantly high activity for PS activation to produce more sulfate radicals (SO 4 - ) and hydroxyl radicals (OH). Therefore, almost 100% BPA (10 mg/L) and 80% TOC can be removed just within 12 min with 1.0 g/L TiO 2-x /rGO and 2 mM PS under visible light. Moreover, it was found that many other typical micropollutants, such as phenol, acetaminophen and sulfamethoxazole can also be effectively degraded by this process. Electron paramagnetic resonance (EPR) and radical quenching experiments indicated that both SO 4 - and OH contribute to the degradation of organics, and the radical process was the main degradation pathway. In addition, the effects of PS concentration, catalyst dosage, initial solution pH and inorganic anions were investigated systematically. Experiments carried out in the real background of water matrix with low-concentration of BPA indicated that the proposed TiO 2-x /rGO-PS-Vis process has strong non-selective photo-oxidative ability for the removal of micropollutants in water., (Copyright © 2018 Elsevier B.V. All rights reserved.)