Zhao Shunzheng, Yi Honghong, Tang Xiaolong, Gao Fengyu, Yu Qingjun, Zhou Yuansong, Wang Jiangen, Huang Yonghai, Yang Zhongyu
Department of Environmental Engineering, College of Civil and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, PR China.
Department of Environmental Engineering, College of Civil and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, PR China; Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, Beijing 100083, PR China.
Ultrason Sonochem. 2016 Sep;32:336-342. doi: 10.1016/j.ultsonch.2016.04.001. Epub 2016 Apr 2.
Ultrasonic effect in the synthesis of catalysts of NiAl oxides prepared starting from the coprecipitation method of a hydrotalcite structure was evaluated in this work. Removal of carbonyl sulfide (COS) at low temperature over the hydrotalcite-derived oxides was studied. The samples were characterized by X-ray Diffraction (XRD), scanning electron microscope (SEM), N2 adsorption/desorption techniques, Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and CO2 temperature-programmed desorption (TPD). It is found that hydrotalcite treated with ultrasonic has smaller average crystallite size and higher particle dispersion compared to hydrotalcite without ultrasonic treatment. As a result, mixed oxides derived from hydrotalcite treated with ultrasonic show more developed pore structure which is good for the physical adsorption of gaseous pollutant. The result of desulfuration test showed that removal efficiency of COS on the NiAl mixed oxides prepared by ultrasonic method (30min) is greater than that on the catalyst prepared without the ultrasonic irradiation assistance with the same aging time. One important reason for the high activity is that when the ultrasonic is used the number of weak basic sites (OH(-) groups) and moderate basic sites (M-O) was increased, whereas the number of strong basic sites (O(2-)) was decreased. Therefore, ultrasonic treatment promoted the COS hydrolysis and suppress the poisoning of the catalyst.
本工作评估了水滑石结构共沉淀法制备的NiAl氧化物催化剂合成过程中的超声效应。研究了水滑石衍生氧化物在低温下去除羰基硫（COS）的性能。通过X射线衍射（XRD）、扫描电子显微镜（SEM）、N2吸附/脱附技术、傅里叶变换红外光谱（FTIR）、X射线光电子能谱（XPS）和CO2程序升温脱附（TPD）对样品进行了表征。结果表明，与未经过超声处理的水滑石相比，经过超声处理的水滑石平均晶粒尺寸更小，颗粒分散性更高。因此，由经过超声处理的水滑石衍生的混合氧化物具有更发达的孔结构，有利于气态污染物的物理吸附。脱硫试验结果表明，超声法（30分钟）制备的NiAl混合氧化物对COS的去除效率高于相同老化时间下未经过超声辐照辅助制备的催化剂。活性高的一个重要原因是，使用超声时，弱碱性位点（OH(-)基团）和中等碱性位点（M-O）的数量增加，而强碱性位点（O(2-)）的数量减少。因此，超声处理促进了COS水解并抑制了催化剂中毒。
