Researchers in China develop new process for direct synthesis of drop-in jet-fuel-range blendstock from lignocellulose
Researchers in China have developed an integrated two-bed continuous flow reactor process for the direct synthesis with high carbon yields (~70%) of dodecanol (C12H26O) or 2,4,8- trimethylnonane (C12H26O2)—a jet-fuel-range C12 branched alkane—from methyl isobutyl ketone (MIBK), which can be derived from lignocellulose.
The dodecanol as obtained can be used as the feedstocks in the production of sodium dodecylsulphate (SDS) and sodium dodecyl benzene sulfonate (SDBS)—widely used as surfactants or detergents. The 2,4,8-trimethylnonane as obtained can be blended into conventional jet fuel without hydroisomerization. A paper on their work is published in the journal ChemSusChem.
MIBK is an important chemical which has been produced in industrial scale from acetone, which in turn is a by-product of the manufacture of bio-butanol and bio-ethanol by the acetone-butanol-ethanol (ABE) fermentation of lignocellulose.
The process developed by the team from the Chinese Academy of Sciences first selectively converts MIBK to a mixture of C12 alcohol and ketone over a Pd modified magnesium-aluminium hydrotalcite (Pd-MgAl-HT) catalyst. They obtained a high total carbon yield (73.0%) of C12 oxygenates under mild conditions: 553 K (280 ˚C) and 0.6 MPa.
In the second bed, the C12 oxygenates generated from the first bed were either hydrogenated to dodecanol over the Ru/C catalyst or hydrodeoxygenated to 2,4,8-trimethylnonane over a Cu/SiO2 catalyst.
|Strategy for the direct production of dodecanol and 2,4,8- trimethylnonane using MIBK and hydrogen over a dual-bed catalyst systems. Sheng et al. Click to enlarge.|
During 24-hour continuous tests, the team found no evident deactivation of the catalysts. In the future, they suggested, it is also possible to synthesize renewable dodecanol and jet fuel range alkanes with hexanol or butanol which can be selectively obtained from the hydrogenolysis of cellulose or 1,4-anhydroerythritol.
This work paves a new way for the synthesis of renewable surfactants and jet fuel range branched alkane with lignocellulosic platform compounds.—Sheng et al.
Sheng, X., Li, N., Li, G., Wang, W., Wang, A., Cong, Y., Wang, X. and Zhang, T. (2016) “Direct Synthesis of Renewable Dodecanol and Dodecane with Methyl Isobutyl Ketone over Dual-Bed Catalyst Systems,” ChemSusChem doi: 10.1002/cssc.201601563