Large heat duty for amine regeneration in absorptionbased CO 2 capture is one of the major drawbacks of this process. Along with a highly endothermic carbamate breakdown reaction in the stripper, the difficulty of proton transfer from protonated amines to water in the amine regeneration process is also considered a basic reason for high heat duty. Transition metal oxide catalysts can play a vital role in decreasing the required thermal energy for amine regeneration in the stripper by providing Bronsted acids and Lewis acids that would help break down the carbamate by direct attack. MEA saturated with CO 2 at 35 °C, with initial loading of 0.56 mole CO 2 /mole amine, was used in this study. The performance of five different transition metal oxide catalysts, V 2 O 5 , MoO 3 , WO 3 , TiO 2 , and Cr 2 O 3 , was studied separately to investigate the effects of these catalysts on amine regeneration in the temperature range of 35−86 °C. It has been observed that MoO 3 performance is much better as it regenerated almost double of the MEA solvent than noncatalytic amine regeneration systems, whereas other catalysts also showed considerable differences in amine regeneration in this temperature range. The amine regeneration performance trend was MoO 3 > V 2 O 5 > Cr 2 O 3 > TiO 2 > WO 3 > blank test. The application of this work would mean that metal oxide catalysts could be used in strippers for a faster CO 2 desorption rate at lower temperature, which would cause a significant reduction of the heat duty.

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In the present study, bimetallic Cu–Mg-supported silica catalysts were prepared by a chemisorption–hydrolysis method with different loadings of copper/magnesium and used for glycerol hydrogenolysis for 1,2-propanediol (1,2-PDO). The Cu catalyst with the base as a promoter showed the highest activity for glycerol hydrogenolysis reaction (glycerol conversion 89.5% and 1,2-PDO selectivity 92.1%). The copper seemed to significantly affect the C–C cleavage and C–O cleavage of glycerol for 1,2-PDO formation. The synthesized catalysts were characterized by N2 sorption, X-ray diffraction (XRD), temperature-programmed desorption of NH3 (TPD-NH3), temperature-programmed reduction of H2 (TPR-H2), X-ray photoelectron spectra (XPS), scanning electron microscopy (SEM), inductively coupled plasma optical emission spectroscopy (ICP-OES), CO chemisorption, Fourier transform infrared (FTIR), and IR analyses of absorbed pyridine. It was found that MgO content influenced the activity of the Cu-supported catalyst. Glycerol hydrogenolysis was found to be highly dependent upon the acidity and reducing property of Cu–Mg-supported silica catalysts. The high catalytic performance of the Cu–Mg-supported/silica catalyst was attributed to the copper dispersion and the existence of Cu+ species and acidic sites. The 1,2-PDO selectivity and glycerol conversion may be easily tuned by the Cu/Mg molar ratio.