Study of Deactivation and Regeneration of ZSM-5 Supported Manganese Nano Catalysts in Combustion of Ethyl Acetate and 2-Propanol

摘要

The deactivation and regeneration of Mn (1 and 2 wt.%)/ZSM-5 nano catalysts during catalytic combustion of ethyl acetate were studied in a fixed bed catalytic reactor at different temperatures. Regeneration of coked catalysts was carried out by thermal (550°C) and oxidative treatment showed a good regeneration performance. The catalyst's activities in fresh and regenerated forms were investigated for combustion of ethyl acetate under an 80 min on stream. During the oxidation process, as the catalytic activity decreases, some of the catalyst pores are blocked and the acid centers are partly covered by coke deposition. The higher performance of Mn/ZSM-5 catalysts was observed at temperature of 350 °C and Mn loading of 2 wt.% where their activities did not considerably change during a run (80 min). The catalysts in fresh and deactivated states were characterized by FTTR and SEM techniques. The nano structure of zeolite ZSM-5 was determined using XRD, SEM and TEM. Furthermore, the effect of reactivity and structure of O-VOCs (ethyl acetate and 2-propanol) were studied on the catalyst deactivation. The 2-propanol was more reactive than ethyl acetate. More coke was formed during ethyl acetate combustion than 2-propanol.