Engineered $\mathrm{Ru}$ on $\mathrm{HY}$ zeolite catalyst for continuous and selective hydrodeoxygenation of lignin phenolics to cycloalkanes under moderate conditions

• Published in: Applied catalysis. A, General Vol. 676
• Main Authors: Adarsh Kumar, Fnu, Kumar, Abhishek, Santosa, Daniel M., Wang, Huamin, Zuo, Peng, Wang, Chongmin, Mittal, Ashutosh, Gieleciak, Rafal, Klein, Darryl P., Manto, Michael, Yang, Bin
• Format: Journal Article
• Language: English
• Published: United States Elsevier 01.03.2024
• Subjects: continuous hydrodeoxygenation; cycloalkanes; engineered catalyst; INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; lignin bio-oil; moderate conditions; sustainable biorefinery
• ISSN: 0926-860X

Here we report a continuous selective hydrodeoxygenation (HDO) process of guaiacol conversion to cycloalkanes under 180 °C/1 MPa, which results in improved HDO chemistry for lignin-based jet fuel production. The incipient wetness impregnation method was modified to prepare an HY zeolite-supported Ru catalyst with better metal dispersion and acid site uniformity, which overcomes the low conversion and selectivity of previous literature. The modified catalyst (Ru-HY-60-MI) was tested in a continuous fixed bed reactor, resulting in increased HDO conversion of guaiacol to cycloalkanes compared to the unmodified catalyst. Pressure, temperature, and weight hourly space velocity-dependent tests validate guaiacol HDO over Ru-HY-60-MI catalyzed ring hydrogenation of guaiacol to 2-methoxycyclohexanol, acid-catalyzed demethoxylation and dehydration to cyclohexene, and further hydrogenation of cyclohexene to cyclohexane. These experiments enable exploring a continuous HDO process, demonstrate effectiveness for other ß-ß and a-O-4 lignin representatives and real lignin bio-oil, and pave the way towards commercialization of lignin-based jet fuel