通过SEM、XRD、FT-IR表征及多孔陶瓷对废水中镍的去除能力,确定多孔陶瓷的制备条件:原料中田菁粉掺杂质量分数为4%,焙烧温度为800℃. SEM和孔结构表征说明,焙烧使多孔陶瓷形貌、结构发生变化;随着焙烧温度的升高,多孔陶瓷的比表面积和孔容呈现降低的趋势,而孔径呈现增大的趋势;EDS分析能表明,原废瓷粉和多孔陶瓷的主要元素组成均为Si、Al、O. SEM、XRD和FT-IR分析表明,多孔陶瓷吸附前后结构稳定. 吸附Ni2+的系列实验表明,多孔陶瓷用量为10 g·L-1,吸附时间为60 min,进水pH值为6.32,进水Ni2+浓度在100 mg·L-1以内.在此条件下废水的Ni2+去除率可达89.7%,多孔陶瓷对废水中镍有较好的去除效果.以制备的多孔陶瓷处理含镍废水,考察多孔陶瓷对废水中Ni2+的吸附动力学和吸附等温线,结果表明,多孔陶瓷对Ni2+的吸附过程符合准二阶动力学模型(R2=0.9999),Qe为9.09 mg·g-1;吸附过程可用Freundlich方程和Langmuir方程来描述,温度由20℃ 升高至40℃,最大吸附量Qm由14.49 mg·g-1上升至15.38 mg·g-1.
The preparation conditions of porous ceramics were determined by SEM, XRD and FT-IR characterizations as well as the nickel removal ability of porous ceramics to be: the mass fraction w of sesbania powder doped was 4%, and the calcination temperature was 800℃. SEM and pore structure characterization illustrated that calcination caused changes in the structure and morphology of waste ceramics. With the increase of calcination temperature, the specific surface area and pore volume decreased, while the aperture increased. EDS analyses showed that the main elements of both the original waste porcelain powder and the porous ceramics were Si, Al and O. The SEM, XRD and FT-IR characterization of porous ceramics illustrated that the structure of porous ceramics was stable before and after adsorption. The series of experiments of Ni2+ adsorption using these porous ceramics showed that when the dosage of porous ceramics was 10 g·L-1, the adsorption time was 60 min, the pH value was 6.32, and the concentration of nickel-containing wastewater was below 100 mg·L-1, the Ni2+ removal of wastewater reached 89.7%. Besides, the porous ceramics showed higher removal efficiency on nickel in the wastewater. The Ni2+-containing wastewater was processed by the porous ceramics prepared, and the adsorption dynamics and adsorption isotherms of Ni2+ in wastewater by porous ceramics were investigated. The research results showed that the Ni2+ adsorption process of porous ceramics was in accordance with the quasi second-order kinetic model (R2=0.9999), with Qe of 9.09 mg·g-1. The adsorption process can be described by the Freundlich equation and Langmuir equation, and when the temperature increased from 20℃ to 40℃, the maximum adsorption capacity Qm increased from 14.49 mg·g-1 to 15.38 mg·g-1.