中空磁性氧化石墨烯的制备及其对亚甲基蓝吸附性能

用共沉淀法将Fe₃O₄沉淀在PS微球上并用甲苯去除PS制备出Fe₃O₄@PS，再用超声将用Hummers法制备的氧化石墨烯包裹在Fe₃O₄@PS表面制备出中空磁性氧化石墨烯，研究了这种复合材料对模拟亚甲基蓝废水的吸附。结果表明：在55℃，用中空磁性氧化石墨烯对亚甲基蓝染料吸附60 min达到平衡，最大吸附量为349.85 mg·g^-1。吸附剂循环8次，吸附效率仍高于80%。用准二级动力学模型可很好地拟合中空磁性氧化石墨烯对亚甲基蓝的吸附。结果表明，吸附速率对亚甲基蓝染料的初始浓度较为敏感，主要为化学吸附。吸附过程符合Langmuir等温吸附模型，说明这种吸附为单层表面吸附。

Preparation of Hollow Magnetic Graphene Oxide and Its Adsorption Performance for Methylene Blue

The Fe₃O₄ coated polystyrene microsphere (PS), namely Fe₃O₄@PS_{was firstly fabricated by co-precipitation method with FeCl2·6H2O and FeCl3 as raw material, and PS microsphere as tempelate. Then Fe3O4@PS was immersed in toluene solution for removing the PS template. Next, the hollow Fe3O4 microsphere was coated with graphene oxide sheets under sonication to produce the hollow magnetic graphene oxide (HMGO). Subsequently, the absorption performance of the HMGO for methylene blue (MB) was assessed in an artificial waste MB solution. Results verified that the adsorption process reach to equilibrium at 55℃ after 60 min. The maximum adsorption capacity of MB on HMGO is 349.85 mg·g^-1. The adsorbent shows good stability and reusability, after 8 times recycling the adsorption rate is still higher than 80%. The adsorption process of MB on HMGO can be well fitted by Pseudo-second-order kinetic model and the adsorption rate is sensitive to the initial concentration. The adsorption isotherm conforms to the Langmuir isotherm model, and the adsorption process is a single-layer surface adsorption.}