(512c) Gasification of a Lignin Surrogate Using Ru Promoted Ni/gAl2O3 Fluidized Catalysts in CREC – Riser Simulator Reactor.

Due the announced depletion of oil, it is necessary to look for alternative energy sources. Biomass energy is one of the most promising technologies to produce syngas. However, the amounts of produced tars and coke must be minimized. Fluidizable catalysts 5%Ni/gAl₂O₃ with low loads of Ru (0.25%, 0.5% and 1% wt) were synthesized using incipient Ni and Ru co-impregnation, characterized using XRD, BET, TPR, TPD and H₂ chemisorption and tested in the gasification of a lignin surrogate in a CREC Riser Simulator reactor, in order to quantify the products (H₂, CO, CO₂ and CH₄) and the amount of coke deposited on the catalyst. Experiments took place at 550°C, 600°C and 650°C using 0.5, 1.0 and 1.5, steam/biomass ratios. The best load of ruthenium was 0.25% and additional increases did not improve the hydrogen molar fraction, but enhanced the partial oxidation. According to TPR, peaks corresponding to Ni and Ru were close each other indicating big interaction between them and great interaction of Ni on the support due its low Ru load (0.25%). The characterizations showed that when Ru is used as a promoter there are decreases in the size of the crystal and the acid site density of the catalyst and the amount of coke deposited on the catalyst is reduced by 60%, when comparing with and without Ru as promoter. These facts indicate that Ni with Ru promote the char gasification and Boudouard reactions. The effect of temperature is qualitatively the same to that at 550°C, obtaining high fractions of CO₂, while as the temperature increases the CO₂ fraction decreases, favoring methane reforming reactions, increasing the CO fraction. Using Aspen Plus, the yields of H₂, CO₂ and CO for all catalysts were very close to equilibrium levels.