Peking U, SINOPEC team develops method for direct conversion of isopropanol to C6+ high-octane blendstock

Researchers from Peking University and SINOPEC have developed a one-post method for the synthesis of C₆₊ branched compounds from isopropanol condenstation on Ni/MoC catalysts. The branched-chain selectivity in C₆₊ and nonnecessity of H₂ give this route advantage in high-octane gasoline blendstock production. Isopropanol can be derived from lignocellulose, making it a potential biomass platform molecule.

An open-access paper on their work appears in the RSC journal Green Chemistry.

The highest C₆₊ production rate reaches 7.5g ∙ g_cat^-1∙ h^-1 over 1.2Ni/MoC with a 100% selectivity of branched carbon chain.

Isopropanol condensation over Ni/MoC catalysts with different Ni loadings. Reaction conditions: isopropanol 1 g, cyclohexane 39 g, catalyst 50 mg (catalyst/isopropanol mass ratio: 0.05), N₂ 1 MPa, 250 °C, 500 rpm, 6 h. Zhou et al.

Additional hydrogen sources or noble metal catalysts are not needed, which shows advantage over the reported ethanol, I/ABE, or acetone condensation routes.

The reaction follows the traditional Guerbet coupling mechanism with the steps of aldol condensation and transfer hydrogenation. The high efficiency of 1.2Ni/MoC catalyst derives from the synergistic effect of Ni metal site and acid site on MoC surface. This study also proposes a strategy to the production of branched carbon chain compounds via the condensation of biomass platform substrates.

—Zhou et al.

Resources

• Wei Zhou, Zirui Gao, Meng Wang, Genghuang Wu, Junfeng Rong and Ding Ma (2022) “Direct conversion of isopropanol to C₆₊ branched compounds as high-octane gasoline blendstock” Green Chemistry doi: 10.1039/D2GC01200F