| Abstrakt: |
There is an increasing demand for practical adsorbents with low cost, high availability, and sustainability, to adsorb and remove radioactive technetium materials. It is imperative to develop high-performance substances that are widely available in nature. In the present study, we used three different natural claystone samples collected from three different areas in the Eastern Desert, Egypt. Cetyltrimethylammonium bromide (CTAB) was mixed with the raw clay samples to prepare modified organoclay, which was used in the removal of technetium. Raw and modified samples were investigated by X-ray diffraction (XRD) analysis, scanning electron microscopy (SEM), and Fourier-transform infrared (FT-IR) spectroscopy. The prepared organoclay samples were then used to remove radioactive technetium materials, applied for healthcare and provided by the Upper Egypt Cancer Institute. In the adsorption processes, three parameters were studied (catalyst weight, contact time, and initial concentration of technetium). Also, kinetic and isothermal models were studied to describe how the adsorption process occurs. The obtained data revealed a maximum removal of 59.4%, 83.6%, and 87.2% for catalyst weight of 0.5 g, 0.4 g, and 0.4 g when using O-Uh2, O-H25, and O-Sy4, respectively. Moreover, the adsorption process followed the pseudo-second-order and intraparticle diffusion kinetic models, while in isothermal studies the adsorption process followed the Freundlich model but not the Langmuir model. This indicates a monolayer with chemical sharing and/or ion exchange formed during the adsorption process. |
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