Partial oxidation of propene to acrylaldehyde with an electrochemical membrane reactor coated with yttria-stabilized zirconia

An electrochemical reactor, constructed from a Sm-doped ceria solid electro lyte (SDC) coated with yttria-stabilized zirconia (YSZ) has been employed f or the partial oxidation of propene at 623-723 K. Upon application of a dir ect current to the reactor, acrylaldehyde is formed at the gold anode, its formation rate linearly increasing with increasing direct current. Selectiv ities to acrylaldehyde, carbon monoxide, and carbon dioxide, based on the c onverted propene, were 36.1, 11.9, and 52%, respectively, at 723 K. The sel ectivity to acrylaldehyde obtained was about 4.2 times higher than that obt ained using SDC alone as a solid electrolyte at 723 K. This result indicate s that the YSZ coating on the anode side of SDC reduces the complete oxidat ion of propene at the cerium oxide surface. In addition, the investigation of the stacked membrane reactor makes it possible to decrease the reaction temperature from 723 to 623 K. (C) 1998 The Electrochemical Society. S1099- 0062(98)07-017-5. All rights reserved.