Upgrading of Lignin-Derived Compounds: Reactions of Eugenol Catalyzed by HY Zeolite and by Pt/γ-Al2O3

Abstract

The conversion of eugenol (4-allyl-2-methoxyphenol), a compound derived from the lignin in woody biomass, was catalyzed by HY zeolite at 573 K and atmospheric pressure. The main products were isoeugenol and guaiacol, formed by isomerization and by deallylation, respectively. Substituted guaiacols with saturated sidechains (4-methylguaiacol, 4-ethylguaiacol, and 4-propylguaiacol) were also formed, by hydrogen transfer and alkylation reactions. The pseudo-first-order rate constant for the overall disappearance of eugenol was found to be 12.4 L (g of catalyst)/h. When the catalyst was Pt/c-Al 2 O 3 used in the presence of H 2 , significant hydrogenation of the propenyl side-chain took place, accompanied by isomerization, and hydrodeoxygenation. Under similar operating conditions, the reaction catalyzed by Pt/c-Al 2 O 3 in the presence of H 2 gave a higher eugenol conversion (X = 0.70) than the reaction catalyzed by HY zeolite (X = 0.11), primarily because of the dominant hydrogenation observed with the former catalyst. In the absence of H 2 as a co-reactant, the acidic c-Al 2 O 3 support in Pt/c-Al 2 O 3 evidently catalyzed all the classes of reactions catalyzed by HY zeolite.

Hydrodeoxygenation of lignin-derived phenolic compounds over bi-functional Ru/H-Beta under mild conditions

“…At temperature of 413 K and with bi-functional 0.5%Ru/H-Beta catalyst, the performance in hydrodeoxygenation of diphenyl ether is better or comparable with literature reports at much higher temperature, e.g. 473 K, and with other catalyst systems [3,[13][14][15][16][17][18][19][20][21][22][23][24][25][26][27], demonstrating the great advantage of our catalyst system. Moreover, no Ru could be detected in the water phase after reaction, indicating no Ru leaching during reaction or the leached Ru below the detection limit.…”

“…Noble metals with high aromatic hydrogenation activity are alternative choices of hydrodeoxygenation catalysts. Palladium [3,[13][14][15][16], platinum [17][18][19], rhodium [20] and ruthenium [21][22] on different supports, e.g. active carbon, metal oxides and zeolites, have been evaluated in the hydrodeoxygenation process.…”

Synthesis of Palladium Nanoparticles Supported on Mesoporous N-Doped Carbon and Their Catalytic Ability for Biofuel Upgrade

“…28,29 Accordingly, the deoxygenation of lignin-derived pyrolysis oil is more challenging than cellulose-derived pyrolysis oil. 12,[30][31][32] Here, we took vanillin (4-hydroxy-3-methoxy benzaldehyde), a common component of pyrolysis oil derived from the lignin fraction, as substrate to explore the principal hydrogenation and deoxygenation routes (Scheme S2). Transformation of carbonyl group to methyl group theoretically proceeds via three ways: i) hydrogenationdehydration mechanism, ii) hydrogenation-hydrogenolytic mechanism and iii) direct hydrogenolysis of C=O bond.…”

Pathways for biomass‐derived lignin to hydrocarbon fuels

“…Nimmanwudipong et al . reported on the catalytic conversion of eugenol over HY zeolite at 300 °C and atmospheric pressure.…”

“…Nimmanwudipong et al 160 reported on the catalytic conversion of eugenol over HY zeolite at 300 o C and atmospheric pressure. Th e main reaction products were isoeugenol and guaiacol, formed by isomerization and dealkylation, respectively.…”