• Spectroscopy and Spectral Analysis
  • Vol. 40, Issue 9, 2869 (2020)
ZHANG Hai-yang1, GAO Bai1、2、*, FAN Hua3, SHEN Wei1, and LIN Cong-ye1
Author Affiliations
  • 1[in Chinese]
  • 2[in Chinese]
  • 3[in Chinese]
  • show less
    DOI: 10.3964/j.issn.1000-0593(2020)09-2869-06 Cite this Article
    ZHANG Hai-yang, GAO Bai, FAN Hua, SHEN Wei, LIN Cong-ye. Mechanism of Fluoride and Arsenic Removal by Ce/γ-Al2O3 Based on XRD and FTIR[J]. Spectroscopy and Spectral Analysis, 2020, 40(9): 2869 Copy Citation Text show less

    Abstract

    The harm caused by fluoride and arsenic in drinking water to public health is a global environmental problem, especially for the high fluorine and arsenic areas without centralized water supply. Compared to other technologies, adsorption to a solid surface is a simple, economical and reliable method for removing arsenic from fluoride. Although the conventional porous adsorbent is stable and inexpensive, the general adsorption amount is not high, and it is difficult to meet the actual needs. Therefore, it is urgent to develop a porous adsorbent which is inexpensive, high-efficiency, and simple in operation flow. The most widely used γ-Al2O3 surface has more -OH, the contact liquid has electrical properties, mainly relying on the surface adsorption site to remove fluorine and arsenic, resulting in limited adsorption effect. After modification, the adsorption process of the adsorbent material is complicated, which has the advantages of surface physical adsorption and pore diffusion. Rare earth element (Ce) is the most abundant element in rare earth. It is widely used in catalysts and alloy additives. Its oxide has high adsorption capacity, but the process of preparing granular rare earth oxide is complicated, and it may cause shedding and metal dissolution during use. And other issues. In order to reduce the process and increase the adsorption capacity of the particulate material, the rare metal salt impregnation method is used to avoid the problems of high cost and low mass production caused by complicated process flow. In this study, the porous adsorption material of y-salt Ce(SO4)2 loaded γ-Al2O3 was prepared by the impregnation method, and the adsorption characteristics of aqueous solution were tested. The adsorption kinetic model and isotherm model were obtained by data fitting to obtain the adsorption process and maximum. The amount of adsorption provides the basis for the adsorption mechanism of Ce/γ-Al2O3. The SEM, XRD and FTIR of the adsorption sorbent performance characterization test qualitatively analyze the adsorption force of Ce/γ-Al2O3 in addition to fluorine and arsenic, providing Ce/γ-Al2O3 Reliable evidence of adsorption mechanism. The results show that the removal of arsenic by fluorine and arsenic in Ce/γ-Al2O3 is in line with the pseudo-secondary kinetics and the Langmuir model. The maximum adsorption capacity of arsenic removal by fluoride can reach 47.842 and 18.518 mg·g-1, respectively. The surface of Ce/γ-Al2O3 is smooth, the load is good, and the combination is stable. Ce(Ⅳ) is reduced to Ce(Ⅲ) to form a Ce—O—Al composite. The main body of Ce/γ-Al2O3 is amorphous, with a small amount of incompletely developed grain structure and stable surface hydroxyl groups. The combination of XRD and FTIR reflects the phase structure and functional group of Ce/γ-Al2O3, which can be used for the identification and analysis of Ce/γ-Al2O3, further verifying the adsorption test process and reflecting the adsorption test phenomenon. γ-Al2O3 is improved by cerium salt Ce(SO4)2 impregnation method, The existence of Al—O and Ce—O, the existence of incomplete grains and the change of crystal structure of surface pore structure are the main controlling factors for the increase of Ce/γ-Al2O3 adsorption.
    ZHANG Hai-yang, GAO Bai, FAN Hua, SHEN Wei, LIN Cong-ye. Mechanism of Fluoride and Arsenic Removal by Ce/γ-Al2O3 Based on XRD and FTIR[J]. Spectroscopy and Spectral Analysis, 2020, 40(9): 2869
    Download Citation