Fe_3O_4@SJC固定床吸附去除亚甲蓝及其再生

Removal of methylene blue by Fe_3O_4 @SJC fixed-bed adsorption and regeneration of Fe_3O_4 @SJC adsorbents

通过热裂解法经一步合成了Fe3O4@SJC复合吸附剂,并对其进行了XRD、SEM结构表征和磁性检测。结果表明,沙棘枝炭(SJC)呈无定形态,Fe3O4晶型为面心立方型。微观负载Fe3O4纳米颗粒使得Fe3O4@SJC复合吸附剂展示出了宏观磁性。运用BBD型响应面法建立了Fe3O4@SJC固定床吸附去除亚甲蓝固定床反应器的吸附模型,对其响应面进行了分析。结果表明,响应面法建立的模型可准确描述吸附过程,且随着流速、浓度的降低和p H的升高,去除率增大。再生实验表明,该铁系非均相Fenton氧化可有效实现吸附剂的再生重复利用。

Fe3O4 @ SJC composite adsorbents are prepared through a one-step thermal cracking method. XRD and SEM are used to characterize the structure. The magnetism is also detected. The results show that seabuekthorn branches carbon （SJC） belongs to amorphous structure, whereas Fe3O4 nanopartieles are face-centered cubic crystalline. The maeroscopically magnetic property of Fe3O4 @ SJC composite adsorbents have been endowed due to the attachment of Fe3O4 nanoparticles. Then,the adsorption model of methylene blue through Fe3O4@ SJC composite adsorbents within the fixed bed reactor are established by using the BBD type of response surface method, and their response surface are analyzed as well. It has been verified that the mode presented above can accurately describe the process of adsorption. With the decrease of the flow rate and concentration, and the increase of the bed height, the removal rate can be enhanced. The regeneration experiments of Fe3O4 @ SJC composite adsorbents show that the heterogeneous Fenton oxidation can effectively realize the regeneration and recycle, and the regeneration mechanism is also discussed.