双金属有机骨架Cu_(1/6)-MOF-5的制备及其低温CO-SCR脱硝性能

Preparation and low-temperature CO-SCR denitration properties of bimetallic organic framework Cu_(1/6)-MOF-5

低温催化剂是CO选择性催化还原(CO-SCR)的关键。本文通过一步溶剂热法成功合成Cu_(1/6)-MOF-5催化剂,利用X射线衍射仪(XRD)、扫描电子显微镜(SEM)、傅里叶红外光谱(FTIR)、拉曼光谱(Raman)、X射线光电子能谱(XPS)对催化剂的结构进行表征。结果表明:掺杂的Cu元素具有Cu^(+)、Cu^(2+)两种价态,且部分取代了MOF-5中的Zn位形成双金属有机骨架Cu_(1/6)-MOF-5。同时,Cu的掺杂增加了氧空位的浓度,从而使得催化剂拥有更高的催化活性,Cu_(1/6)-MOF-5的脱硝率在160℃时达到89%,在200℃时达到95%,分别比相应温度下MOF-5的脱硝率高57%和25%;即使在含硫环境中,其在200℃时的脱硝率仍大于87%。

Low-temperature catalyst is the key to CO-selective catalytic reduction(CO-SCR).Cu_(1/6)-MOF-5catalyst was successfully synthesized by one-step solvothermal method.X-ray diffractometer(XRD),scanning electron microscope(SEM),Fourier transform infrared spectroscopy(FTIR),Raman spectroscopy(Raman)and X-ray photoelectron spectroscopy(XPS)were used to characterize the structure of the catalysts.The results show that the doped Cu exists in+1 and+2 valence states and partially replaces the Zn site in MOF-5 to form the bimetallic organic framework Cu_(1/6)-MOF-5.At the same time,the Cu doping increases the concentration of oxygen vacancies,so that the catalyst has higher catalytic activity.Specifically,the denitrification rate of Cu_(1/6)-mof-5 catalyst increases from 32%to 89%at 160℃and from 70%to 95%at 200℃.Even in the sulfurcontaining environment,the NO conversion rate can still reach 87%at 200℃.