Catalytic performance of palladium/degraded chitosan for acetylene selective hydrogenation Scientific paper

Abstract

The aim of this paper was to investigate the catalytic properties of palladium supported on chitosan catalysts. The effect of primitive chitosan and degraded chitosan on catalytic performance was compared. The structure, mor­phology, metal content and properties of the catalysts were characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), inductively coupled plasma spectrometry (ICP), X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET) method and X-ray photoelectron spectroscopy (XPS). The results showed that the catalytic performance of Pd/degraded chitosan was better than that of Pd/chitosan at a certain Pd load. Pd/degraded chitosan (degradation 4 h) catalyst exhibited excellent catalytic performance and stability. The acetylene conversion and ethylene selectivity, respectively, achieved 100 and 91 %. During 13.5 h, the acetylene conversion maintained 100 % and the ethylene selectivity decreased slightly from 88 to 71 %. Based on this study, it was demonstrated that Pd was successfully coordinated with chitosan; after degradation, the chitosan particles became smaller and had larger surface areas; these were conducive to improve the catalytic performance of Pd/degraded chitosan. Pd/degraded chitosan also had high selectivity at high conversion, greatly improving the characteristics of low selectivity at high con­version of traditional Pd-based catalysts.