Hydrogen-rich gas production by steam and oxidative steam reforming of crude glycerol over Ni-La-Me mixed oxide catalysts (Me= Ce and/or Zr)

ROMERO, MARIANO; DUARTE, HERNÁN; VEIGA, SANTIAGO; SEGOBIA, DARÍO; BUSSI, JUAN; FACCIO, RICARDO; APESTEGUÍA, CARLOS

CATALYSIS TODAY

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2018

0920-5861

The production of H2-rich gaseous mixtures from steam and oxidative steam reforming of crude glycerol was investigated on catalysts with general formula Ni(12wt.%)-La2(Ce1-xZrx)2O7 (x= 0, 0.5, 1). The catalysts were prepared by the polymerized complex method based on the Pechini-type reaction route and characterized by a variety of physical and spectroscopic techniques. Samples were calcined in air at 850 ºC for 4 h. All catalysts showed a well-defined NiO phase and a mixed oxide with a general formula A2B2O7 (A: La; B: Ce and/or Zr). NiO was completely reduced to metallic Ni on all catalysts under pure H2 at 650 °C. Ni reducibility is favored by the presence of Ce. Redox properties of Ce can also explain a synergetic effect leading to the higher basicity of the catalyst containing Ce and Zr (x=0.5). Catalytic tests were performed at 650 ºC by feeding the fixed-bed tubular reactor with a crude glycerol:water solution containing 30 wt% glycerol. The best results were achieved on the catalyst displaying the highest basicity (Ni-La2(Ce0.5Zr0.5)2O7 both under steam and oxidative reforming conditions. Removal of carbon and alkali metals by simple procedures allows to recover the initial catalytic activity without no changes in their chemical and phase structure.