除氟载锆生物复合吸附剂的制备及应用

Preparation and Application of Zirconium Loaded Biological Composite Adsorbent for Defluorination

摘要: 通过表面沉降技术将氧化锆固载到用丰年虫卵壳孔道内表面，制备载氧化锆生物复合材料(LC-Zr)。扫描电镜(SEM)、能谱分析(EDS)、透射电镜(TEM)及X衍射(XRD)观察结果显示孔道只是在原有大小的基础上缩小，无颗粒团聚及孔道堵塞现象，氧化锆颗粒粒径未超过50 nm，以涂布的方式固载到卵壳孔道内表面，证明孔道呈现递进式阶梯分布的丰年虫卵壳和常规载体材料相比，具有大孔强化传质效应双重作用机制，较之传统载体材料表现出明显优势。通过吸附性能研究，发现在常规阴离子SO₄^2- 、Cl-和NO₃^- 存在下，100 mL的含氟污水(F− = 10.00 mg/L)仅用0.8 g的LC-Zr投加30 min，除氟率可达91.73%；且LC-Zr对氟离子的吸附性基本上不受pH值的影响。动力学实验也表明LC-Zr的吸附容量大，具有良好的除氟效果。研究初步证明了丰年虫卵壳作为生物载体材料在载锆复合吸附剂的制备中起到的独特作用，为含氟废水的净化及环境友好型复合吸附剂的研制提供理论基础。

Abstract: Zirconia was immobilized on the inner surface of the foramen of the eggshell of Artemiasalina by surface settling technology to prepare zirconia loaded biological composite (LC-Zr). The results of scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), transmission electron microscopy (TEM) and X-ray diffraction (XRD) show that the pore canal is only reduced on the basis of the original size, and there is no particle agglomeration and pore blockage phenomenon. The particle size of zirconia is not more than 50 nm, and it is loaded onto the inner surface of the egg-shell pore by coating. It is proved that the pore presents progressive ladder distribution of the eggshell and conventional distribution of the eggshell compared with the traditional carrier material; the carrier material has the double action mechanism of large pore enhanced mass transfer effect, and has obvious advantages. Through the study of adsorption performance, it was found that in the presence of conventional anions SO₄^2- , Cl− and NO₃^- 100 mL of fluorine-containing sewage (F− = 10.00 mg/L) was only added with 0.8 g of LC-Zr for 30 min with a fluorine removal rate of 91.73%, and the adsorption of LC-Zr on fluorine ions was basically not affected by pH value. The kinetic experiments also showed that LC-Zr had a large adsorption capacity and a good defluorination effect. The research preliminarily proved that the eggshell of the foraminifera played a unique role in the preparation of zirconium loaded composite adsorbent, which provided a theoretical basis for the purification of fluorine-containing wastewater and the development of environment-friendly composite adsorbent.