Modification of Ni/ZrO2 catalyst by selected rare earth metals as a promising way for increase in the efficiency of thermocatalytic conversion of lignocellulosic biomass to hydrogen-rich gas

Abstract

The main goal of this work was the evaluation of the effect of modification of zirconia by selected rare earth metals (praseodymium, yttrium and gadolinium) on the activity of nickel catalyst in the high temperature conversion of lignocellulosic biomass to hydrogen-rich gas. An influence of type of dopant, its content and introduction method was studied. The obtained results revealed that the modification of catalysts allowed for noticeable increase the efficiency of hydrogen-rich gas production in the high temperature conversion of lignocellulosic feedstock. The highest activity among studied catalysts was observed for nickel supported on zirconium oxide modified by praseodumium via sol-gel method. The performed experiments (XRD, XPS, TEM, TPR, TPD-NH3, TG-DTA-MS and BET) indicated that an increase in the activity of investigated catalysts can be not only related with larger surface area, pore volume and higher acidity, but also size and location of active phase crystallites, susceptibility of nickel oxide to the reduction and contribution of Pr3+ ions in zirconia lattice.