CATALYTIC TRANSFER HYDROGENATION OF GLUCOSE TO SORBITOL OVER RANEY NICKEL

• Main Author: RAHMI NIM:20515010, HIJRATUR
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/27862
• Institution: Institut Teknologi Bandung

<p align="justify">Conversion of biomass to renewable fuels and fine chemicals has attracted attention of researchers. Cellulose is a major component in biomass and may produce glucose by a hydrolysis process. Hydrogenation of glucose results in sorbitol. Sorbitol is one of sugar alcohols with various applications in beverages, pharmacy, cosmetics, and personal care. The hydrogenation of glucose into sorbitol is of high importance because this synthetic route is an efficient and economical way in producing sorbitol. However, such a process requires high pressure of hydrogen gas as a source of hydrogen and employs precious metals as catalyst (i.e., ruthenium, rhodium, palladium, and platinum). The low abundance availability and good activity in hydrogenation process. Nickel is one of the metals that may be used as a catalyst in the hydrogenation process. In this study, a porous nickel was employed as a catalyst in hydrogenation reaction of glucose into sorbitol in the absence of hydrogen gas. RaNi was prepared in two steps. First step was a preparation of nickel aluminium alloy from Ni(II) and Al(III). Second step was a leaching process of Al(0) from the alloy to produce porous Ni, commonly called as Raney Ni (RaNi). RaNi was characterized using XRD and N2 physisorption. The results of x-ray diffraction showed typical patterns of nickel(0) at 44.51(rumus) (111), 51.85(rumus) (200), and 76.37(rumus) (220). Characterization of the alloy with N2 physisorption gave information of a surface area of 64 m2/g and a pore diameter of 6.13 nm. The hydrogenation reaction was carried out for 6 h at 80 (rumus)C with isopropyl alcohol (IPA) as a source of hydrogen. No hydrogen gas was used in this hydrogenation tests. The product was analysed using 1H-NMR by observing the chemical shift of methyne and methylene protons of sorbitol at 3.53(rumus)3.78 ppm and by 3,5-dinitrosalysilic acid (DNS) test to determine the residual glucose in the product. The product tested by DNS test showed that the amount of converted glucose was 54% when synthesized-RaNi was employed as the catalyst.<p align="justify">