Hydrogenolysis of biomass-derived
furfural (FFA) to 1,2-pentanediol
(1,2-PeD) was investigated using a bifunctional catalyst with basic
and metallic sites, which was synthesized by the hydrothermal method.
The synthesized catalyst consisting of rhodium (Rh) supported on an
octahedral molecular sieve (OMS-2) of different loadings, such as
0.5, 1, and 1.5% w/w, was studied, and 1% (w/w) loading gave the best
results. This 1% w/w Rh/OMS-2 catalyst showed excellent catalytic
activity and selectivity for the hydrogenolysis reaction because of
better dispersion of rhodium, later revealed by characterization.
Furthermore, 1% Rh/OMS-2 catalyst was well characterized in virgin
and reused states using various techniques such as Fourier-transform
infrared spectroscopy, NH
3
-temperature-programmed desorption
(TPD), CO
2
-TPD, temperature-programmed reduction, H
2
pulse chemisorption, scanning electron microscopy, high-resolution
transmission electron microscopy, X-ray diffraction, Brunauer–Emmett–Teller
surface area, X-ray photoelectron spectroscopy, Raman spectroscopy,
and differential scanning calorimetry–thermogravimetry analysis.
The catalyst showed a higher surface area of 72 m
2
/g and
the average size of the highly dispersed Rh metal of ∼2 nm.
The studies were performed in a batch reactor; the catalyst offered
almost 100% conversion of FFA with 87% selectivity to 1,2-PeD at 160
°C and 30 atm hydrogen pressure in 8 h. The reaction mechanism
and kinetic model have been developed using a dual-site Langmuir–Hinshelwood–Hougen–Watson
mechanism. The activation energies were 12.3 and 27.6 kcal/mol, correspondingly.
The catalyst was found to be active, selective, and reusable.