Investigation of hydrogenation reactions of glucose

Sorbitol is one of the top 12 target chemicals according to the U.S. Department of Energy's Biomass Program classification. This versatile substance is obtained by the catalytic hydrogenation method, which is carried out in the presence of chemical catalysts, which stand out among many production methods and whose properties and advantages vary depending on their type. In this study, nickel and copper catalysts prepared according to the sol-gel method were used to examine the sorbitol production process from glucose. ZrO2 and SiO2 were preferred as supporting materials. Catalyst composition, particularly the proportions of nickel and copper, has played a key role in determining the outcomes of hydrogenation reactions. The study was carried out under various reaction conditions (different temperature, pressure, time and catalyst amount). While the temperature values varied between 125 and 200 oC, the pressure was taken between 2.5 and 4 MPa. Time variables were made between half an hour and six hours. A series of experiments were carried out to determine the ideal Ni-Cu ratio as well as suitable reaction conditions to reduce undesirable byproducts and increase sorbitol efficiency and selectivity. High Pressure Liquid Chromatography device was used to determine the reaction products. BET surface analysis to characterize the 15Ni15Cu/SiO2 catalyst, which was determined to be the most effective catalyst. X-Ray Diffraction (XRD), X-Ray Photoelectron Spectroscopy (XPS), Transmission Electron Microscopy (TEM) and Scanning electron microscopy (SEM) analyzes were performed. Sorbitol efficiency varied from 0% to 100%. 100% sorbitol was obtained using 15Ni15Cu/SiO2 catalyst; In this case, the reaction conditions are; The temperature was determined as 175°C, the duration as 5 hours, the amount of 0.3 g catalyst and the H2 pressure as 3.5MPa. In addition, the experiments conducted for the reusability of the ideal catalyst (15Ni15Cu/SiO2) in our study also revealed extremely satisfactory results.