Jiang Zhao, Cao Bo, Su Guangxia, Lu Yan, Zhao Jiaying, Shan Dexin, Zhang Xiuyuan, Wang Ziyi, Zhang Ying
School of Resource and Environment, Northeast Agricultural University, Harbin 150030, China.
Biomed Res Int. 2016;2016:7183951. doi: 10.1155/2016/7183951. Epub 2016 Nov 30.
This study selected solid wastes, such as rice husk ash (RHA), inactive powder (ISP), and rice husk (RH), as the potential adsorbents for the removal of Fe(II) and Mn(II) in aqueous solution. The structural characteristics, functional groups, and elemental compositions were determined by scanning electron microscope (SEM) and Fourier translation infrared spectrum (FT-IR) analyses, respectively. Then the influence on the Fe(II) and Mn(II) removing efficiency by the factors, such as pH, adsorbent dosage, initial Fe(II) and Mn(II) concentration, and contact time, was investigated by the static batch test. The adsorption isotherm study results show that Langmuir equation can better fit the Fe(II) and Mn(II) adsorption process by the three adsorbents. The maximum adsorption amounts for Fe(II) were 6.211 mg/g, 4.464 mg/g, and 4.049 mg/g by RHA, ISP, and RH and for Mn(II) were 3.016 mg/g, 2.229 mg/g, and 1.889 mg/g, respectively. The adsorption kinetics results show that the pseudo-second-order kinetic model can better fit the Fe(II) and Mn(II) adsorption process. D-R model and thermodynamic parameters hint that the adsorption processes of Fe(II) and Mn(II) on the three adsorbents took place physically and the processes were feasible, spontaneous, and exothermic.
本研究选取了稻壳灰（RHA）、惰性粉末（ISP）和稻壳（RH）等固体废物作为去除水溶液中Fe(II)和Mn(II)的潜在吸附剂。分别通过扫描电子显微镜（SEM）和傅里叶变换红外光谱（FT-IR）分析确定了其结构特征、官能团和元素组成。然后通过静态批量试验研究了pH值、吸附剂用量、初始Fe(II)和Mn(II)浓度以及接触时间等因素对Fe(II)和Mn(II)去除效率的影响。吸附等温线研究结果表明，Langmuir方程能更好地拟合三种吸附剂对Fe(II)和Mn(II)的吸附过程。RHA、ISP和RH对Fe(II)的最大吸附量分别为6.211 mg/g、4.464 mg/g和4.049 mg/g，对Mn(II)的最大吸附量分别为3.016 mg/g、2.229 mg/g和1.889 mg/g。吸附动力学结果表明，准二级动力学模型能更好地拟合Fe(II)和Mn(II)的吸附过程。D-R模型和热力学参数表明，Fe(II)和Mn(II)在三种吸附剂上的吸附过程为物理吸附，且该过程可行、自发且放热。
