TY - JOUR
T1 - Demethoxylation of guaiacol and methoxybenzenes over carbon-supported Ru-Mn catalyst
AU - Ishikawa, Momoko
AU - Tamura, Masazumi
AU - Nakagawa, Yoshinao
AU - Tomishige, Keiichi
N1 - Funding Information:
This study is supported by JSPS KAKENHI grant number 26249121 and 15K06564 . We also acknowledge the Technical Division in the School of Engineering in Tohoku University for TEM measurements.
PY - 2016/3/1
Y1 - 2016/3/1
N2 - Hydrodeoxygenation of methoxybenzenes such as guaiacol over Ru catalyst was studied. Guaiacol was demethoxylated and then hydrogenated over carbon black supported Ru-MnOx catalyst (Ru-MnOx/C) forming cyclohexanol and methanol in good yield (81% and 86%, respectively) under relatively mild conditions (433K, H2 1.5MPa). Over Ru-MnOx/C, yield of demethoxylated products (cyclohexanol and cyclohexane) was almost the same as that of methanol, suggesting that the methoxy group is eliminated by demethoxylation to form methanol. Other methoxybenzenes such as 2,6-dimethoxyphenol and anisole were also converted to demethoxylated saturated compounds such as cyclohexanol and cyclohexane. The reaction scheme was proposed where demethoxylation and total hydrogenation of aromatic ring from partially-hydrogenated adsorbed guaiacol proceeded in parallel. Lower H2 pressure and higher reaction temperature were advantageous to demethoxylation. Addition of MnOx species slowed down the reaction rate of total hydrogenation of aromatic ring, which increased the relative rate of the elimination of methoxy group to that of total hydrogenation before the elimination. The catalyst can be reused without significant loss of activity. The nanoparticles of Ru and Mn were highly dispersed, and the state of Mn species on Ru-MnOx/C during the reaction was weakly basic MnO.
AB - Hydrodeoxygenation of methoxybenzenes such as guaiacol over Ru catalyst was studied. Guaiacol was demethoxylated and then hydrogenated over carbon black supported Ru-MnOx catalyst (Ru-MnOx/C) forming cyclohexanol and methanol in good yield (81% and 86%, respectively) under relatively mild conditions (433K, H2 1.5MPa). Over Ru-MnOx/C, yield of demethoxylated products (cyclohexanol and cyclohexane) was almost the same as that of methanol, suggesting that the methoxy group is eliminated by demethoxylation to form methanol. Other methoxybenzenes such as 2,6-dimethoxyphenol and anisole were also converted to demethoxylated saturated compounds such as cyclohexanol and cyclohexane. The reaction scheme was proposed where demethoxylation and total hydrogenation of aromatic ring from partially-hydrogenated adsorbed guaiacol proceeded in parallel. Lower H2 pressure and higher reaction temperature were advantageous to demethoxylation. Addition of MnOx species slowed down the reaction rate of total hydrogenation of aromatic ring, which increased the relative rate of the elimination of methoxy group to that of total hydrogenation before the elimination. The catalyst can be reused without significant loss of activity. The nanoparticles of Ru and Mn were highly dispersed, and the state of Mn species on Ru-MnOx/C during the reaction was weakly basic MnO.
KW - Demethoxylation
KW - Guaiacol
KW - Hydrodeoxygenation
KW - Manganese oxide
KW - Ruthenium
UR - http://www.scopus.com/inward/record.url?scp=84942288204&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84942288204&partnerID=8YFLogxK
U2 - 10.1016/j.apcatb.2015.09.021
DO - 10.1016/j.apcatb.2015.09.021
M3 - Article
AN - SCOPUS:84942288204
VL - 182
SP - 193
EP - 203
JO - Applied Catalysis B: Environmental
JF - Applied Catalysis B: Environmental
SN - 0926-3373
ER -