Porous polyvinyl fluoride coated cellulose beads for efficient removal of Cd(II) from phosphoric acid

Recent trends in the phytoremediation of radionuclide contamination of soil by cesium and strontium: Sources, mechanisms and methods: A comprehensive review

This comprehensive review examines recent trends in phytoremediation strategies to address soil radionuclide contamination by cesium (Cs) and strontium (Sr). Radionuclide contamination, resulting from natural processes and nuclear-related activities such as accidents and the operation of nuclear facilities, poses significant risks to the environment and human health. Cs and Sr, prominent radionuclides involved in nuclear accidents, exhibit chemical properties that contribute to their toxicity, including easy uptake, high solubility, and long half-lives. Phytoremediation is emerging as a promising and environmentally friendly approach to mitigate radionuclide contamination by exploiting the ability of plants to extract toxic elements from soil and water. This review focuses specifically on the removal of 90Sr and 137Cs, addressing their health risks and environmental implications. Understanding the mechanisms governing plant uptake of radionuclides is critical and is influenced by factors such as plant species, soil texture, and physicochemical properties. Phytoremediation not only addresses immediate contamination challenges but also provides long-term benefits for ecosystem restoration and sustainable development. By improving soil health, biodiversity, and ecosystem resilience, phytoremediation is in line with global sustainability goals and environmental protection initiatives. This review aims to provide insights into effective strategies for mitigating environmental hazards associated with radionuclide contamination and to highlight the importance of phytoremediation in environmental remediation efforts.

Design of Bismuth Tungstate Bi2WO6 Photocatalyst for Enhanced and Environmentally Friendly Organic Pollutant Degradation

In this study, a chemical precipitation approach was adopted to produce a photocatalyst based on bismuth tungstate Bi2WO6 for enhanced and environmentally friendly organic pollutant degradation. Various tools such as X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM), optical spectroscopy and X-ray photoelectron spectroscopy, were employed to assess the structural and morphological properties. Hence, the XRD profiles showed a well crystallized Bi2WO6 orthorhombic phase. The photocatalytic performance of the resulting photocatalyst was assessed by the decomposition of Rhodamine B (RhB) and methyl orange (MO) with a decomposition efficiency of 97 and 92%, along with the highest chemical oxygen demand of 82 and 79% during 120 min of illumination, respectively. The principal novelty of the present work is to focus on the changes in the crystalline structure, the morphology, and the optical and the photoelectrochemical characteristics of the Bi2WO6, by tuning the annealing temperature of the designed photocatalyst. Such physicochemical property changes in the as-prepared photocatalyst will affect in turn its photocatalytic activity toward the organic pollutant decomposition. The photocatalytic mechanism was elaborated based on electrochemical impedance spectroscopy, photocurrent analysis, photoluminescence spectroscopy, and radical trapping measurements. The overall data indicate that the superoxide O2•- and holes h+ are the principal species responsible for the pollutant photodegradation.

Cellulose beads supported CoFe2O4: A novel heterogeneous catalyst for efficient rhodamine B degradation via advanced oxidation processes

In this study, a novel mechanical process was used to produce cellulose beads (CB). These beads were then doped with cobalt ferrite nanoparticles (CoFe2O4 NPs) to serve as catalysts for the degradation of rhodamine B (RhB) through peroxymonosulfate (PMS) activation. The physical and chemical properties of CoFe2O4 and CoFe2O4@CB catalysts were characterized using X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) combined with energy dispersive X-ray spectrometer (EDX), scanning transmission electron microscopy (STEM) techniques, and thermogravimetric analysis (TGA). To optimize RhB degradation efficiency, Response Surface Methodology (RSM) was employed, utilizing the Box-Behnken design (BBD). Under the optimized conditions of a catalyst dosage of 0.40 g/L, PMS dosage of 0.98 mM, RhB concentration of 40 mg/L, pH of 5.27, and reaction time of 60 min, a remarkable degradation efficiency of 98.51 % was achieved at a temperature of 25 °C. In quenching experiments, 1O2, SO4•-, and HO• species are produced in the CoFe2O4@CB/PMS system, with 1O2, and SO4•- species dominating RhB degradation. Remarkably, the new CoFe2O4@CB catalyst has demonstrated exceptional stability and reusability, validated by recycling tests (up to 78 % of RhB degradation efficiency after a 5-cycle experiment) and subsequent characterizations (FTIR, SEM, and EDX) emphasizing unchanged bands, uniform distribution, and consistent composition after reuse cycles. These results demonstrate the effectiveness of mechanically produced CoFe2O4@CB catalysts for advanced oxidation processes (AOPs), with promising applications in wastewater treatment.