Departamento de Ecología, Facultad de Ciencias, Universidad de Granada, 18071, Spain; Instituto del Agua, Universidad de Granada, 18071, Spain.
Departamento de Física Aplicada, Facultad de Ciencias, Universidad de Granada, 18071, Spain.
Chemosphere. 2017 Mar;171:571-579. doi: 10.1016/j.chemosphere.2016.12.101. Epub 2016 Dec 21.
We propose a novel magnetic adsorbent for optimal Phosphorus (P) removal from the upper sediment layers. For this aim, magnetic chitosan microparticles were prepared using a reverse-phase suspension cross-linking technique. The resulting particles and suspensions were characterized using scanning electron microscopy, X-ray powder diffraction, Fourier transform infrared spectroscopy, magnetometry, thermogravimetric analysis, electrophoretic mobility and turbidity measurements. The hybrids are multicore particles consisting of well dispersed magnetite nanoparticles (approx. 10% w/w) homogeneously distributed within the biopolymer matrix. These microparticles can be easily separated from the water column and sediment using magnetic field gradients. Their P adsorption capacity is evaluated in batch conditions resulting in a maximum P adsorption capacity of M = 4.84 mg g at pH = 7. We demonstrate that these particles are excellent candidates to remove P from water column and also P mobile from the upper sediment layers due to two main reasons: they sediment slower and present lower potential toxicity (due to a their larger size) than conventional iron/iron oxide microparticles previously proposed for lake restoration.
我们提出了一种新颖的磁性吸附剂，用于从上层沉积物中最佳去除磷 (P)。为此，使用反相悬浮交联技术制备了磁性壳聚糖微球。使用扫描电子显微镜、X 射线粉末衍射、傅里叶变换红外光谱、磁强计、热重分析、电泳迁移率和浊度测量对所得颗粒和悬浮液进行了表征。这些混合物是多核心颗粒，由分散良好的磁铁矿纳米颗粒（约 10%w/w）均匀分布在生物聚合物基质中组成。这些微球可以使用磁场梯度轻松地从水柱和沉积物中分离出来。在批处理条件下评估它们的磷吸附能力，结果表明在 pH=7 时最大磷吸附容量为 M=4.84mg/g。我们证明，由于两个主要原因，这些颗粒是从水柱中去除 P 以及从上层沉积物中去除移动 P 的优秀候选物：它们的沉降速度较慢，并且由于其较大的尺寸，潜在毒性较低（与之前用于湖泊修复的常规铁/氧化铁微球相比）。
