TY - JOUR
T1 - Influence of support for ru and water role on product selectivity in the vapor-phase hydrogenation of levulinic acid to γ-valerolactone: Investigation by probe-adsorbed fourier transform infrared spectroscopy
AU - Velisoju, Vijay Kumar
AU - Peddakasu, Ganga Bhavani
AU - Gutta, Naresh
AU - Boosa, Venu
AU - Kandula, Manasa
AU - Chary, Komandur V.R.
AU - Akula, Venugopal
N1 - Generated from Scopus record by KAUST IRTS on 2023-10-23
PY - 2018/8/30
Y1 - 2018/8/30
N2 - Ru supported on activated carbon, Al2O3, and MgO was assessed for the hydrogenation of levulinic acid (LA) to γ-valerolactone (GVL). Role of H2O on the hydrogenation activity of Ru was studied by probe-adsorbed diffuse-reflectance infrared Fourier transform (DRIFT) spectroscopy. Ru supported on activated carbon showed a maximum productivity of 1.18 kgGVL kgcatalyst -1 h-1 with an insignificant loss in the activity after 72 h of continuous operation in the presence of H2O. Using pure LA, GVL rate was decreased by an order of magnitude (0.12 kgGVL kgcatalyst -1 h-1) within 6 h of reaction time. The physicochemical characteristics of the catalysts were examined by temperature-programmed desorption of NH3, CO pulse chemisorption, H2-temperature-programmed reduction, and X-ray photoelectron spectroscopy techniques. H2O-adsorbed DRIFT spectroscopic data revealed the reversible generation of surface -OH groups when aqueous LA was used as the substrate; consequently, Ru/C catalyst stability was also improved. Finally, on the basis of the kinetic and in situ spectroscopic data, a plausible surface-reaction mechanism is proposed for the vapor-phase LA hydrogenation to GVL in the presence of H2O over the carbon-supported Ru catalyst.
AB - Ru supported on activated carbon, Al2O3, and MgO was assessed for the hydrogenation of levulinic acid (LA) to γ-valerolactone (GVL). Role of H2O on the hydrogenation activity of Ru was studied by probe-adsorbed diffuse-reflectance infrared Fourier transform (DRIFT) spectroscopy. Ru supported on activated carbon showed a maximum productivity of 1.18 kgGVL kgcatalyst -1 h-1 with an insignificant loss in the activity after 72 h of continuous operation in the presence of H2O. Using pure LA, GVL rate was decreased by an order of magnitude (0.12 kgGVL kgcatalyst -1 h-1) within 6 h of reaction time. The physicochemical characteristics of the catalysts were examined by temperature-programmed desorption of NH3, CO pulse chemisorption, H2-temperature-programmed reduction, and X-ray photoelectron spectroscopy techniques. H2O-adsorbed DRIFT spectroscopic data revealed the reversible generation of surface -OH groups when aqueous LA was used as the substrate; consequently, Ru/C catalyst stability was also improved. Finally, on the basis of the kinetic and in situ spectroscopic data, a plausible surface-reaction mechanism is proposed for the vapor-phase LA hydrogenation to GVL in the presence of H2O over the carbon-supported Ru catalyst.
UR - https://pubs.acs.org/doi/10.1021/acs.jpcc.8b06003
UR - http://www.scopus.com/inward/record.url?scp=85052369799&partnerID=8YFLogxK
U2 - 10.1021/acs.jpcc.8b06003
DO - 10.1021/acs.jpcc.8b06003
M3 - Article
SN - 1932-7455
VL - 122
SP - 19670
EP - 19677
JO - JOURNAL OF PHYSICAL CHEMISTRY C
JF - JOURNAL OF PHYSICAL CHEMISTRY C
IS - 34
ER -