Sorption characteristics of bismuth tungstate nanostructure for removal of some radionuclides from aqueous solutions

Cesium adsorption from an aqueous medium for environmental remediation: A comprehensive analysis of adsorbents, sources, factors, models, challenges, and opportunities

Considering the widespread and indispensable nature of nuclear energy for future power generation, there is a concurrent increase in the discharge of radioactive Cs into water streams. Recent studies have demonstrated that adsorption is crucial in removing Cs from wastewater for environmental remediation. However, the existing literature lacks comprehensive studies on various adsorption methods, the capacities or efficiencies of adsorbents, influencing factors, isotherm and kinetic models of the Cs adsorption process. A bibliometric and comprehensive analysis was conducted using 1179 publications from the Web of Science Core Collection spanning from 2014 to 2023. It reviews and summarizes current publication trends, active countries, adsorption methods, adsorption capacities or efficiencies of adsorbents, tested water sources, influencing factors, isotherm, and kinetic models of Cs adsorption. The selection of suitable adsorbents and operating parameters is identified as a crucial factor. Over the past decade, due to their notable capacity for Cs adsorption, considerable research has focused on novel adsorbents, such as Prussian blue, graphene oxide, hydrogel, and nanoadsorbents (NA). However, there remains a need for further development of application-oriented laboratory-scale experiments. Future research directions should encompass exploring adsorption mechanisms, developing new adsorbents or their combinations, practical applications of lab-scale studies, and recycling radioactive Cs from wastewater. Drawing upon this literature review, we present the most recent research patterns concerning adsorbents to remove Cs, outline potential avenues for future research, and delineate the obstacles hindering effective adsorption. This comprehensive bibliometric review provides valuable insights into prevalent research focal points and emerging trends, serving as a helpful resource for researchers and policymakers seeking to understand the dynamics of adsorbents for Cs removal from water.

A review on bismuth-based materials for the removal of organic and inorganic pollutants

Modernized lifestyle and increased industrialization threaten living organisms because of the pollutants released from industries and household wastes. The presence of even small amounts of pollutants (organic pollutants (OPs) and inorganic pollutants-heavy metals (HMs)) shows significant effects. Thus wastewater treatment is urgently needed before being subjected to use. Many methods and materials have been developed and reported for the removal of pollutants from wastewater. This review focused on the removal of both OPs and HMs using bismuth-based (Bi-based) materials because of their low toxicity and excellent properties compared to other metals. Bi-based materials as a photocatalyst for photodegradation of OPs are discussed in detail with synthesis methods. Further, since few reviews are available on the Bi-based material for the removal and sensing of HMs, this topic was intentionally summarized. About 200 published articles and reviews have been reviewed here. Additionally, the key point that needs to be focused on the development of Bi-based photocatalysts for the removal of OPs and for upgrading the Bi-based materials as adsorbents for HMs are conferred in the outlook. This will help many researchers in their upcoming work.

Engineered magnetic oxides nanoparticles as efficient sorbents for wastewater remediation: a review

The rapid urbanization and industrialization is causing worldwide water pollution, calling for advanced cleaning methods. For instance, pollutant adsorption on magnetic oxides is efficient and very practical due to the easy separation from solutions by an magnetic field. Here we review the synthesis and performance of magnetic oxides such as iron oxides, spinel ferrites, and perovskite oxides for water remediation. We present structural, optical, and magnetic properties. Magnetic oxides are also promising photocatalysts for the degradation of organic pollutants. Antimicrobial activities and adsorption of heavy metals and radionucleides are also discussed.

Novel adsorbent based on carbon-modified zirconia/spinel ferrite nanostructures: Evaluation for the removal of cobalt and europium radionuclides from aqueous solutions

Herein, a novel adsorbent based on carbon-modified zirconia/spinel ferrite (C@ ZrO₂/Mn_0.5Mg_0.25Zn_0.25Fe₂O₄) nanostructures were chemically prepared to remove ⁶⁰Co and ^152+154Eu radionuclides from liquid media using batch experiments. The XRD pattern confirms the successful preparation of the C@ZrO₂/MnMgZnFe₂O₄ composite. Also, SEM and TEM images confirmed that the composite owns a heterogeneous morphology in the nanoscale range. The optical band gap value of Mn_0.5Mg_0.25Zn_0.25Fe₂O₄, ZrO₂, and the composite samples was 1.45, 2.38, and 1.54 eV, respectively. Many parameters have been studied as the effect of time, solution pH, and initial ion concentration. The kinetics models for the removal process of ^152+154Eu and ⁶⁰Co radionuclides were studied. The second-order kinetic equation could describe the sorption kinetics for both radionuclides. The Langmuir monolayer capacity for ⁶⁰Co was 82.51 mg/g and for ^152+154Eu was 136.98 mg/g. The thermodynamic parameters such as free energy ΔG^o, the enthalpy ΔH^o, and the entropy ΔS^o were calculated. The results indicated that the sorption process has endothermic nature for both two radionuclides onto C@ZrO₂/MnMgZnFe₂O₄ composite.