Hydrodeoxygenation
Hydrodeoxygenation (HDO) is a hydrogenolysis process for removing oxygen from oxygen-containing compounds. Typical HDO catalysts commonly are sulfided nickel-molybdenum or cobalt-molybdenum on gamma alumina. An idealized reaction is:[1]
- R2O + 2 H2 → H2O + 2 RH
The first review on HDO was published in 1983.[2] HDO is of interest in producing biofuels, which are derived from oxygen-rich precursors like sugars or lipids. An example of a biomass refining process employing hydrodeoxygenation is the NEXBTL process.
HDO of biomass fast pyrolysis vapors under low hydrogen pressures have recently attracted a lot of attention. Bulk molybdenum trioxide (MoO3) was used as catalyst and found to completely deoxygenate cellulose, corn stover, and lignin pyrolysis vapors and produce a stream of hydrocarbons including aromatics, alkenes, and alkanes.[3][4] From an economic viewpoint, only aromatics and alkenes should ideally be produced to enable product incorporation into the existing infrastructure.
References
- Henrik Topsøe, Bjerne S. Clausen, Franklin E. Massoth "Hydrotreating Catalysis" Springer, 1996. ISBN 3540603808.
- Furimsky, Edward (2000-06-12). "Catalytic hydrodeoxygenation". Applied Catalysis A: General. 199 (2): 147–190. doi:10.1016/S0926-860X(99)00555-4.
- Shanks, Brent H.; Zhang, Jing; Nolte, Michael W. (2015-12-21). "Ex situ hydrodeoxygenation in biomass pyrolysis using molybdenum oxide and low pressure hydrogen". Green Chemistry. 18 (1): 134–138. doi:10.1039/C5GC01614B. ISSN 1463-9270.
- Shanks, Brent H.; Saraeian, Alireza; Nolte, Michael W. (2017-07-31). "Hydrodeoxygenation of cellulose pyrolysis model compounds using molybdenum oxide and low pressure hydrogen". Green Chemistry. 19 (15): 3654–3664. doi:10.1039/C7GC01477E. ISSN 1463-9270.