Article pubs.acs.org/est
Fast and Selective Preconcentration of Europium from Wastewater and Coal Soil by Graphene Oxide/Silane@Fe3O4 Dendritic Nanostructure Santanu Patra,† Ekta Roy,† Rashmi Madhuri,*,† and Prashant K. Sharma‡ †
Department of Applied Chemistry, Indian School of Mines, Dhanbad, Jharkhand 826 004, India Functional Nanomaterials Research Laboratory, Department of Applied Physics, Indian School of Mines, Dhanbad, Jharkhand 826 004, India
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S Supporting Information *
ABSTRACT: In this study, nanocomposite of graphene oxide and silane modified magnetic nanoparticles (silane@Fe3O4) were synthesized in a form of dendritic structure. For this, silane@Fe3O4 nanoparticle gets sandwiched between two layers of graphene oxide by chemical synthesis route. The synthesized dendritic structure was used as a monomer for synthesis of europium ion imprinted polymer. The synthesis of imprinted polymer was contemplated onto the surface of the vinyl group modified silica fiber by activated generated free radical atom-transfer radical polymerization, that is, AGET-ATRP technique. The synthesized dendritic monomer was characterized by XRD, FT-IR, VSM, FE-SEM, and TEM analyses. The imprinted polymer modified silica fiber was first validated in the aqueous and blood samples for successful extraction and detection of europium ion with limit of detection = 0.050 pg mL−1 (signal/noise = 3). The imprinted polymer modified silica fiber was also used for preconcentration and separation of europium metal ion from various soil samples of coal mine areas. However, the same silica fiber was also used for wastewater treatment and shows 100% performance for europium removal. The findings herein suggested that dendritic nanocomposite could be potentially used as a highly effective material for the enrichment and preconcentration of europium or other trivalent lanthanides/actinides in nuclear waste management.
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INTRODUCTION Any type of activity that uses or produces radioactive materials generates radioactive waste. Various processes in industry, defense, medicine, scientific research, nuclear power generation and mining produce byproducts that include radioactive waste. Radioactive waste can be in any physical state like gas, liquid, or solid form and their level of radioactivity may vary from sample to sample. The waste can remain radioactive for a few hours or several months or even hundreds of thousands of years. Because it can be so hazardous and can remain radioactive for so long, finding suitable disposal facilities for radioactive waste is difficult. Therefore, proper disposal and removal is essential to ensure protection of the health and safety of the public and quality of the environment including air, soil, and water supplies. As an important goal in radioactive waste treatment, efficient immobilization of radioactive actinides and lanthanides in groundwater, wastewater, soil, etc. attract intense research interest. Europium [Eu (III)] is usually chosen as a chemical analogue of trivalent lanthanides [Ln (III)] and actinides [An (III)] in nuclear waste.1 Because investigation of Eu (III) adsorption behavior on the solid−liquid interface between the adsorbent and adsorbate can help predict the effectiveness of adsorbents for radionuclides without the risks of radioactive © XXXX American Chemical Society
exposure. Not only this, with a content of 0.000106% in earth, Eu (III) is one of the most expensive rare earth elements and an important element in various fields (like industrial, material science, electronics and life science).2 The conflict between increasing demand in the various industries and the limited amount of Eu (III) highlights the need for the efficient recovery of the Eu (III). On the darker side of Eu, it is a toxic element and can cause various diseases in the human body after contamination in the human body fluid. A threshold value of 6 mg L−1 has been reported for Eu in the literature.3 However, exposure at its low concentrations (
