Catalytic acetylene hydration over the Zn/Zr-MCM catalyst: Effect of preparation methods for doping zirconia on catalytic performance

Abstract

The ordered mesoporous Zr-modified MCM-41 materials were synthesized by using four different preparation methods including impregnation method, precipitation method, ultrasound method and trituration method, respectively; active zinc species were immobilized on the modified materials with different methods for introducing zirconia species as effective catalysts for the acetylene hydration. All the synthesized materials were characterized by various techniques including BET, FTIR, XRD, TGA, TEM, XPS, NH3-TPD, H2-TPR, and solid-stated UV–vis. The correlation between structural properties of zirconia modified support and catalytic performance of the Zn catalysts was evaluated in detailed in the acetylene hydration. It is demonstrate that the Zr-modified materials showed the excellent thermostability, and zirconia species addition could enhance the interactions between active metal and support, as well as control the metal particles size with better dispersion. In addition, the substantial enhancement of acid sites and total acid quantity for the modified materials were contributed to the zirconia species addition. Besides, activity evaluation confirms that the Zn/ZM-P catalyst showed more optimistic catalytic performance above 92% C2H2 conversion and 85% selectivity to acetaldehyde in the acetylene hydration due to the stronger metal-support interactions and more acid sites. The study would provide scientific basis for the design of metal catalysts.