Selective transformation of bioethanol into acetaldehyde over highly efficient metallic nanoparticles (Pt, Ru) supported on basic KL zeolite

Abstract

Bioethanol obtained from agriculture products (corn, sugarcane, etc) is largely used as additive in transportation fuels. However, the upgrading of ethanol to produce valuable chemicals, either for application as direct fuel or as chemical intermediates (i.e. butanol, acetone) is an interesting subject of research [1]. The more feasible transformations of ethanol by heterogeneous catalysis are those yielding ethylene or acetaldehyde. It can be used as a raw material for the production of acetic acid, acetic anhydride, ethyl acetate, butyl aldehyde, crotonaldehyde, pyridine, peracetic acid, vinylacetate and many other products [2]. In this communication we present the catalytic properties of two noble metals, Pt and Ru, supported over one KL zeolite and its derivative Ba impregnated sample (BaKL). Also for comparative purposes a high surface area graphite (HSAG) was used as support. The two metals were introduced by incipient wetness impregnation using Pt(NH3)4(OH)2¿xH2O and Ru(NH3)4(OH)2¿xH2O in the case of KL and HSAG supported. The catalysts were characterized by HRTEM in order to determine the metallic sizes and particle distributions, after reduction under H2 at 673K. The tests of catalytic behavior were conducted in a fixed bed flow reactor feeding ethanol (either pure or containing water at 10%) in an inert gas carrier He. The analysis of the reaction products was performed using an on-line gas chromatograph apparatus.