Hydrogen transfer between hydrocarbons and oxygenated compounds in co-processing bio-oils in FCC

R. PUJRO; M. PANERO; M. BERTERO; U. SEDRAN; M. FALCO

ENERGY & FUELS (PRINT)

AMER CHEMICAL SOC

Lugar: Washington; Año: 2019 vol. 33 p. 6473 - 6482

0887-0624

Oxygenated model compounds representing typical components of bio-oilsand a hydrocarbon hydrogen donor agent were used to study hydrogen transferreactions between hydrocarbons and oxygenated compounds when co-processed overacidic commercial FCC catalysts. Phenol, syringol, and trimethoxybenzene wereeach mixed with tetralin at 5 wt%. individually in benzene as an inert solvent.The mixtures were reacted in a fluidized bed, batch CREC Riser Simulatorlaboratory reactor during 10 s contact time with catalyst to oil relationshipof 3 at 500 ºC over a commercial equilibrium FCC catalyst, conditions beingselected in order to simulate FCC bio-oil ? VGO co-processing. Tetralin wasalso reacted alone at 5 wt%. in benzene to gather background information. Whentetralin was the only reactant, its conversion was 87 %, most importantreactions being hydrogen transfer, as shown by the yield of naphthalene, andcracking. Alkylation and disproportionation were also observed to a lowerextent. In the experiments with the mixtures, the oxygenated compoundsconverted completely and tetralin converted to less than half the conversionwhen pure. In these experiments, as compared to pure tetralin, the yield ofgases and C11+ hydrocarbons increased and the yield of cokedecreased, showing the interaction between the hydrocarbon and the modeloxygenated compounds reactants. The index SHT,which shows the selectivity to hydrogen transfer reactions from tetralin, increasedsignificantly, to about two times, in the experiments with the mixtures.Moreover, coke from pure tetralin showed to be qualitatively different fromthat in the experiments with the mixtures, where it was more condensed, thusconfirming that the reaction pathways are dissimilar.