Mitigating Green Oil Deactivation in Acetylene Hydrogenation Using Carbon-Supported Pd Catalysts

Abstract

This study investigates the mitigation of green oil deactivation in acetylene hydrogenation using carbon-supported Pd catalysts. Various carbon supports including CMK-3, short CMK-3, activated carbon, graphite, mesoporous carbon, graphite nanofiber, and carbon nanotube, are compared. Catalyst performance, including deactivation rates and product selectivity, is evaluated under high acetylene concentration conditions. Comprehensive characterization of catalyst properties is conducted using techniques such as scanning electron microscope, Ar physisorption, X-ray photoelectron spectroscopy, Raman spectroscopy, CO chemisorption, and thermogravimetric analysis. The study reveals that carbon-supported catalysts generally exhibit slower deactivation rates compared to alumina-supported catalysts. Among carbon supports, carbon nanotube demonstrates exceptional stability, while graphite shows rapid deactivation. The catalyst surface area shows the strongest correlation with the deactivation rate, suggesting that the larger the surface area, the easier it is for the generated green oil to escape without covering the active Pd sites. These findings highlight the importance of textural properties in designing stable catalysts for acetylene hydrogenation and emphasize the need for a holistic approach to catalyst design.