Dalia R. Abd El-Hafiz, Mohamed A. Ebiad
Abstract
Ultra-fine Ce–Co and Cox/Ce–La (x = 4 and 10%) solid solutions (SS) were prepared for the first time by spray freezing technology, and evaluated in bio-ethanol steam reforming reaction for H2 production. The catalysts were characterized by DLS, XRD, BET and TEM, in order to reveal the structure activity relationship. It was shown that, the addition of La3+ cation to Ce–Co catalyst lead to 100% ethanol conversion at lower reaction temperature (300 °C). Hydrogen selectivity was higher on Ce–Co catalyst than on Cox/Ce–La and increase by increase Co content. Moreover, Cox/Ce–La catalysts provided highest deactivation resistant during 15 h. Characterization of spent catalysts revealed that, the addition of La as a promoter to Ce–Co catalyst preventing sintering at high temperatures. TGA analysis indicates the formation of very small amounts of amorphous carbon on Co10/Ce–La catalyst, while CNT was formed on Ce–Co which responsible for deactivation processes. Both oxygen vacancy and La2O2CO3 acted as carbon scavengers during ESR reaction over Cox/Ce–La.
Keywords
Cobalt; Ceria; Lanthanum; Nano-structures; Spray freeze drying; Hydrogen production