Impacts of preparation method on catalytic properties and activity of Shell@Core structure of CuO@ZrO2/FeMgAl-LDO catalyst for ethanol dehydrogenation

Abstract

Core-shell particles is a type of materials that consist of an inner core structure and an outer shell made from different components. They have been employed as a catalyst due to their unique properties, arising from the combination of the core and shell materials. In addtion, the properties of the core-shell particles can be designed using several suface modification techniques in order to improve the activity and stability of the catalyst. Chemical grafting is a surface modification method that involves the reaction between a metal alkoxide precursor and the surface hydroxyl group of a support. This technique has been reported to be one of the most interesting surface modification techniques that provide a well-dispersed metal oxide on the surface of a support. Micro-emulsion is also considered as one of the simplest and effective methods for the preparation of nano-sized particles with a narrow size distribution, which can be immobilized on the surface of a support. In this work, the impact of preparation methods on the physical and chemical properties of the CuO@ZrO 2 /FeMgAl-LDO shell@core catalyst and 1,3-butadiene production were investigated. The catalyst samples were characterized using several techniques, including XRD, XRF, BET, NH 3 -TPD, CO 2 -TPD, TEM-EDX, and SEM-EDX. The activity of catalyst samples on ethanol conversion was performed in a continuous U-tube fixed-bed reactor at 400 ​°C and atmospheric pressure. It was found that the conversion of ethanol to 1,3-butadiene was a surface sensitive reaction. Therefore, the specific catalyst preparation method was required in order to achieve a high 1,3-butadiene yield. Particularly, in this case, the catalyst that provided the highest yield of 1,3-butadiene was in the form of ZrO 2 -grafted granular catalyst (CuO@gf-ZrO 2 /g-FeMgAl-LDO one). Based on the characterization results, the grafted granular core-shell catalyst was the one that had the highest ratio of total base/acid sites. • Impact of preparation methods on the properties of shell@core catalyst and 1,3-butadiene production. • Core-shell catalysts with a CuO shell and grafted and micro-emulsioned ZrO 2 /powder and granule FeMgAl-LDO cores. • It was found that transformation of ethanol to 1,3-butadiene was a surface sensitive reaction. • A specific catalyst preparation method was required in order to achieve a high 1,3-butadiene yield. • The catalyst with grafted granular core provided the highest 1,3-butadiene yield, owing to the highest base/acid ratio.