删除或更新信息,请邮件至freekaoyan#163.com(#换成@)

纳米磁性磷酸二氢钙对Cd的吸附、回收与再生

本站小编 Free考研考试/2021-12-31

中文关键词磁性磷酸二氢钙纳米Cd2+吸附 英文关键词magneticcalcium dihydrogen phosphatenanoparticlesCd2+adsorption
作者单位E-mail
李玉娇西南大学资源环境学院, 农村清洁工程重庆市工程研究中心, 重庆 4007161170742896@qq.com
杨志敏西南大学资源环境学院, 农村清洁工程重庆市工程研究中心, 重庆 400716bear@swu.edu.cn
陈玉成西南大学资源环境学院, 农村清洁工程重庆市工程研究中心, 重庆 400716
黄磊西南大学资源环境学院, 农村清洁工程重庆市工程研究中心, 重庆 400716
唐海燕西南大学资源环境学院, 农村清洁工程重庆市工程研究中心, 重庆 400716
中文摘要 以Ca(H2PO42、铁盐与亚铁盐为原料,采用共沉淀法制备成纳米磁性材料Ca(H2PO42@Fe3O4(NMCDP),研究其对Cd2+的吸附、回收与再生效果.透射电镜(TEM)、红外光谱(FTIR)、X射线衍射(XRD)显示,NMCDP粒径约60 nm,稳定性良好,饱和磁化强度为30.9 emu·g-1.吸附动力学表明,NMCDP对Cd2+的吸附1 h之内即可达到平衡,符合准二级动力学模型.吸附热力学表明,NMCDP对Cd2+的吸附符合Langmuir与Freundlich等温吸附模型,最大吸附量为142.50 mg·g-1.在pH值由2增加到3时,吸附量随溶液初始pH值的升高而增加,当pH值大于3后,逐渐保持稳定;溶液中共存离子Na+、Mg2+、Cu2+对材料吸附Cd2+均有一定的影响,影响程度Cu2+ > Mg2+ > Na+.采用0.01 mol·L-1 HCl与EDTA-Na2均可解吸出部分吸附的Cd2+,以EDTA-Na2解吸率较高,达到68%,从而实现NMCDP的再生. 英文摘要 In order to improve the adsorption-separation of Cd2+ in water treatment, magnetic Fe3O4 coated Ca(H2PO4)2 nanoparticles (NMCDP) were developed by coprecipitation. The properties of these nanoparticles were characterized by transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and magnetization curves. Experiments were carried out to investigate the effect of adsorption, reclaiming, and regeneration. The results showed that NMCDP was a stable material with a particle size of 60 nm and a saturation magnetization of 30.9 emu·g-1. The adsorption rate of Cd2+ by NMCDP was fast, and adsorption equilibrium could be achieved within 1 hour. The kinetic data were well fitted by a pseudo-second-order model, and the isotherm adsorption data agreed with the Langmuir and Freundlich model, with a maximum adsorption capacity of 142.50 mg·g-1. The adsorption capacity of Cd2+ was affected by the pH and increased when the pH was increased from 2 to 3, while with continued increase of the pH of the solution, the adsorption capacity gradually became stable. The coexisting ions in the solution had an effect on the adsorption of Cd2+, especially the divalent cation Cu2+. The NMCDP could be regenerated by using 0.01 mol·L-1 HCl and EDTA-Na2, and the results indicated that it could be recycled with a desorption rate of 68% by EDTA-Na2 solution.

PDF全文下载地址:

https://www.hjkx.ac.cn/hjkx/ch/reader/create_pdf.aspx?file_no=20190438&flag=1&journal_id=hjkx&year_id=2019

相关话题/工程 农村 重庆 西南大学 资源