To remove cesium ions from water and soil, a novel adsorbent was synthesized by following a one-step co-precipitation method and using non-toxic raw materials. By combining ammonium-pillared montmorillonite （MMT） an...To remove cesium ions from water and soil, a novel adsorbent was synthesized by following a one-step co-precipitation method and using non-toxic raw materials. By combining ammonium-pillared montmorillonite （MMT） and magnetic nanoparticles （Fe304）, an MMT/ Fe304 composite was prepared and characterized. The adsorbent exhibited high selectivity of Cs＊ and could be rapidly separated from the mixed solution under an external magnetic field. Above all, the adsorbent had high removal efficiency in cesium-contaminated samples （water and soil） and also showed good recycling performance, indicating that the MMT/Fe304 composite could be widely applied to the remediation of cesium-contaminated environments. It was observed that the pH, solid/liquid ratio and initial concentration affected adsorption capacity. In the presence of coexisting ions, the adsorption capacity decreased in the order of Ca2 〉 M 〉 IC 〉 Na＋, which is consistent with our theoretical prediction. The adsorption behavior of this new adsorbent could be expressed by the pseudo-second-order model and Freundlich isotherm. In addition, the adsorption mecha- nism of Cs was NH4 ion exchange and surface hydroxyl group coordination, with the former being more predominant.展开更多
基金supported by the Special Scientific Research Fund of Public Welfare Profession (Environmental Protection) of China (no.201509074)
文摘To remove cesium ions from water and soil, a novel adsorbent was synthesized by following a one-step co-precipitation method and using non-toxic raw materials. By combining ammonium-pillared montmorillonite （MMT） and magnetic nanoparticles （Fe304）, an MMT/ Fe304 composite was prepared and characterized. The adsorbent exhibited high selectivity of Cs＊ and could be rapidly separated from the mixed solution under an external magnetic field. Above all, the adsorbent had high removal efficiency in cesium-contaminated samples （water and soil） and also showed good recycling performance, indicating that the MMT/Fe304 composite could be widely applied to the remediation of cesium-contaminated environments. It was observed that the pH, solid/liquid ratio and initial concentration affected adsorption capacity. In the presence of coexisting ions, the adsorption capacity decreased in the order of Ca2 〉 M 〉 IC 〉 Na＋, which is consistent with our theoretical prediction. The adsorption behavior of this new adsorbent could be expressed by the pseudo-second-order model and Freundlich isotherm. In addition, the adsorption mecha- nism of Cs was NH4 ion exchange and surface hydroxyl group coordination, with the former being more predominant.
