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The one-pot direct conversion of levulinic acid (LA) to 1,4-pentanediol (1,4-PDO) was investigated over a trimetallic Zn-promoted Cu–Ni alloy on a H-ZSM-5 (Cu–Ni–Zn/H-ZSM-5) catalyst. Under mild reaction conditions at 130 °C and a H2 pressure of 2.5 MPa for 6 h in an aqueous medium, almost complete conversion of LA to high-yield 1,4-PDO (93.4%) was achieved. The presence of the Zn promoter effectively suppressed the growth of the Cu–Ni alloy nanoparticles (NPs) on the surface of H-ZSM-5. Consequently, the reducibility of the Cu–Ni–Zn alloy was much higher than that of the Cu–Ni alloy. The numerous Lewis acid sites of the Cu–Ni–Zn/H-ZSM-5 catalyst enhanced the adsorption of LA, and the adsorbed LA was converted to γ-valerolactone (GVL) at the Brønsted acid sites of H-ZSM-5 followed by hydrogenation at the Cu–Ni alloy sites. Subsequently, the readsorption of GVL was activated at the Lewis acid sites and GVL underwent ring opening, followed by hydrogenation to form 1,4-PDO at the Cu–Ni alloy sites. The H2 spillover on the Zn-promoted Cu–Ni alloy NPs enhanced the hydrogenation of LA to 1,4-PDO. Because of the mild reaction conditions, the formation of coke and active site sintering was highly suppressed. In addition, metal leaching did not occur over the trimetallic Cu–Ni–Zn/H-ZSM-5 catalyst. Consequently, the Cu–Ni–Zn/H-ZSM-5 catalyst could be used for up to five cycles with minimal activity loss.

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Hydroconversion of dicyclopentadiene (DCPD) into high energy density jet propellant JP-10 has been successfully achieved with a greener single-step route over supported gold catalyst. The physicochemical properties of the catalysts were studied with XRD, SEM, TEM, N 2 -adsorption, NH 3 -TPD. The influence of reaction conditions like temperature, pressure, time etc. were studied in detail. The studies reveal that pressure and temperature play crucial roles in the reaction. Moderate acid sites in the catalysts are chiefly involved in isomerization and gold catalyzes hydrogenation of the intermediates. Analysis of the product stream at different intervals indicates a dissociation-recombination mechanism for the reaction. Reusability of the catalyst was tested by conducting five runs with the same catalyst. Even after the fifth run, the catalyst retains relatively high conversion and selectivity to exo-tetrahydrodicyclopentadiene (exo-THDCPD). † Electronic supplementary information (ESI) available. See

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