Title
One-pot production of dioctyl ether from 1,2-octanediol over rutile-titania-supported palladium-tungsten catalyst
Author
Yoshinao Nakagawa, Hiroki Hayasaka, Takehiro Asano, Masazumi Tamura, Kazu Okumura, Keiichi Tomishige
Year
2020
Journal
Molecular Catalysis
Abstract
Direct synthesis of dioctyl ether by catalytic reduction of 1,2-octanediol (1,2-OcD) was investigated with various supported catalysts containing W and noble metals. The combination of rutile TiO2 support and Pd with W showed the highest yield of dioctyl ether, up to ca. 45 % (carbon-based). The catalytic activity much depended on the W loading amount, and the amount corresponded to monolayer coverage or more was necessary to obtain good yield. The data at low conversion levels showed that the reaction started with WOx/TiO2-catalyzed dehydration of 1,2-OcD to octanal, which then reacted with 1,2-OcD to give acetal. The stepwise hydrogenolysis of the acetal gave dioctyl ether. The WOx-Pd/TiO2 was significantly deactivated during uses, and the deactivated catalyst even lost the activity in 1,2-OcD dehydration. The characterization results of the used catalyst were not much different from the fresh one with XRD, Raman, NH3-TPD, IR of adsorbed pyridine and XAFS techniques. Metastable minor site on WOx/TiO2 was probably responsible to the catalytic activity.
Instrument
NRS-5100
Keywords
EtherTungsten, Rutile titania, Dehydration, Hydrodeoxygenation