饮用水氟砷对公众健康造成的危害是一个全球性的环境问题, 对于无集中供水的高氟砷地区显得尤为突出。 与其他技术相比, 固体表面吸附方法是一种操作简单、 经济通用且效果可靠的除氟除砷的方法。 尽管传统多孔吸附剂稳定廉价, 但普遍吸附量不高, 难以满足实际需要, 因此亟待研发廉价高效和操作流程简单的多孔吸附剂。 使用最为广泛的γ-Al2O3表面存在较多—OH, 接触液体具有电性, 主要依靠表面吸附点位除氟除砷, 导致其吸附效果有限。 经过改性, 吸附材料吸附过程复杂化, 使其具有表面物理吸附和孔扩散等优点。 稀土元素(Ce)是稀土中最多的元素, 普遍用于催化剂和合金添加剂, 其氧化物具有较高的吸附能力, 但制备颗粒稀土氧化物工艺繁杂, 并且使用过程中可能会产生脱落和金属溶出等问题。 为了能够减少工艺程序并提高颗粒材料的吸附量, 使用稀有金属盐浸渍法, 避免复杂工艺流程带来的成本高、 量产低等问题。 故此创新性采用浸渍法制备铈盐Ce(SO4)2负载γ-Al2O3的多孔吸附材料, 开展水溶液吸附特征试验, 通过数据拟合得出吸附动力学模型和等温线模型, 获得吸附过程及最大吸附量, 给出Ce/γ-Al2O3吸附机理依据, 通过测试SEM, XRD和FTIR, 定性分析Ce/γ-Al2O3除氟除砷的吸附作用力, 为Ce/γ-Al2O3提供可靠的吸附机理证据。 结果表明: Ce/γ-Al2O3除氟除砷较符合拟二级动力学和Langmuir模型, 除氟除砷最大吸附量分别可达47.842和18.518 mg·g-1。 Ce/γ-Al2O3表面光滑, 负载良好, 结合稳定。 Ce(Ⅳ)被还原成Ce(Ⅲ), 形成Ce-O-Al复合物, Ce/γ-Al2O3主体为非定型结构, 有少量发育不完整晶粒结构存在, 表面羟基健型稳定。 XRD与FTIR相结合, 反映出Ce/γ-Al2O3的物相结构及官能团种类, 可用于Ce/γ-Al2O3的鉴定与分析, 进一步验证吸附试验过程, 体现吸附试验现象。 γ-Al2O3经铈盐Ce(SO4)2浸渍法改进, 造成Al—O健和Ce—O健、 不完整晶粒的存在、 表面孔径结构晶型结构的变化是Ce/γ-Al2O3吸附量提高的主控因素。

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.