GTS-UAB Research Group, Department of Chemistry, Facultat de Ciències, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain.
GTS-UAB Research Group, Department of Chemistry, Facultat de Ciències, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain.
J Environ Sci (China). 2022 Nov;121:1-12. doi: 10.1016/j.jes.2021.09.001. Epub 2022 Jan 31.
In this study, a commercial cube-shaped open-celled cellulose sponge adsorbent was modified by in-situ co-precipitation of superparamagnetic iron oxide nanoparticles (SPION) and used to remove As(V) from aqueous solutions. Fe K-edge X-ray absorption spectroscopy (XAS) and TEM identified maghemite as the main iron phase of the SPION nanoparticles with an average size 13 nm. Batch adsorption experiments at 800 mg/L showed a 63% increase of adsorption capacity when loading 2.6 wt.% mass fraction of SPION in the cube-sponge. Experimental determination of the adsorption thermodynamic parameters indicated that the As(V) adsorption on the composite material is a spontaneous and exothermic process. As K-edge XAS results confirmed that the adsorption enhancement on the composite can be attributed to the nanoparticles loaded. In addition, adsorbed As(V) did not get reduced to more toxic As(III) and formed a binuclear corner-sharing complex with SPION. The advantageous cube-shape of the sponge-loaded SPION composite together with its high affinity and good adsorption capacity for As(V), good regeneration capability and the enhanced-diffusion attributed to its open-celled structure make this adsorbent a good candidate for industrial applications.
在这项研究中，采用原位共沉淀法制备了超顺磁性氧化铁纳米粒子（SPION）对商用的立方体形开孔纤维素海绵吸附剂进行了改性，并将其用于从水溶液中去除 As(V)。Fe K 边 X 射线吸收光谱（XAS）和 TEM 鉴定出磁铁矿是 SPION 纳米粒子的主要铁相，平均粒径为 13nm。在 800mg/L 的浓度下进行的批量吸附实验表明，当立方海绵中负载 2.6wt.%的 SPION 时，吸附容量增加了 63%。吸附热力学参数的实验测定表明，复合材料对 As(V)的吸附是自发的放热过程。As K 边 XAS 结果证实，吸附增强归因于负载的纳米粒子。此外，吸附的 As(V)没有被还原为更具毒性的 As(III)，而是与 SPION 形成双核角共享配合物。负载 SPION 的海绵的有利的立方形状，对 As(V)的高亲和力和好的吸附容量，良好的再生能力以及由于其开孔结构而增强的扩散，使这种吸附剂成为工业应用的良好候选材料。
