Ji Ying-Xue, Wang Feng-He, Zhang Fan, Zhang Yan-Hong, Wang Guo-Xiang, Gu Zhong-Zhu
School of Energy and Mechanical Engineering, Nanjing Normal University, Nanjing 210042, China.
Environmental Science and Engineering, Nanjing Normal University, Nanjing 210023, China.
Huan Jing Ke Xue. 2013 Oct;34(10):3912-20.
Under different conditions of initial rice husk ash (RHA) dosage, oscillating temperature, oscillating frequency and solution pH, the adsorption characteristics of sulfanilamide on RHA with the change of time and its adsorption kinetics were investigated. RHA was characterized by SEM and FTIR before and after sulfanilamide adsorption. The results indicated that the adsorption characteristics of sulfanilamide on RHA was influenced by RHA dosage, oscillating temperature, oscillating frequency and solution pH. Within the RHA dosing range (0. 1-2.0 g.L-1) in this experiment, the optimal temperature for the adsorption was 25C , and with the increase of RHA dosage, the removal efficiency of sulfanilamide increased, the time required to reach adsorption equilibrium was shortened and the adsorptive quantity of sulfanilamide by per unit mass of RHA decreased. A high oscillating frequency was used to ensure the adsorption effect when the RHA concentration was high. Strong acidic and strong alkaline conditions were conducive to the adsorption of sulfanilamide. The analysis of adsorption dynamics showed that for the adsorption process with high RHA dosage ( >or= 1.0 g.L-1), the pseudo-second-order model fitted the adsorption behavior well, and the process was controlled by physical and chemical adsorption. Intraparticle diffusion model showed that the adsorption process was controlled by both membrane diffusion and internal diffusion, and the influence of the former became more obvious with the increase of the adsorbent concentration. Both the SEM and FTIR spectra proved the effective adsorption of sulfanilamide by RHA.
在不同的初始稻壳灰（RHA）投加量、振荡温度、振荡频率和溶液pH值条件下，研究了磺胺在RHA上的吸附特性随时间的变化及其吸附动力学。在磺胺吸附前后，通过扫描电子显微镜（SEM）和傅里叶变换红外光谱（FTIR）对RHA进行了表征。结果表明，磺胺在RHA上的吸附特性受RHA投加量、振荡温度、振荡频率和溶液pH值的影响。在本实验的RHA投加量范围（0.1 - 2.0 g·L-1）内，吸附的最佳温度为25℃，随着RHA投加量的增加，磺胺的去除效率提高，达到吸附平衡所需的时间缩短，单位质量RHA对磺胺的吸附量降低。当RHA浓度较高时，采用较高的振荡频率以确保吸附效果。强酸性和强碱性条件有利于磺胺的吸附。吸附动力学分析表明，对于高RHA投加量（≥1.0 g·L-1）的吸附过程，准二级模型能很好地拟合吸附行为，该过程受物理和化学吸附控制。颗粒内扩散模型表明，吸附过程受膜扩散和内扩散共同控制，且随着吸附剂浓度的增加，前者的影响变得更加明显。SEM和FTIR光谱均证明了RHA对磺胺的有效吸附。
