Raney nickel synthesis for glucose hydrogenation without hydrogen gas

Abstract

Hydrogenation of glucose into sorbitol has been a concern of researchers for a long time because it is an efficient and economical way of producing sorbitol. The researchers look for alternative metals that are higher in abundance and have good hydrogenation activity, such as nickel. In this study, porous nickel was prepared and used as a catalyst for the hydrogenation of glucose to sorbitol without adding hydrogen gas. The porous nickel needs two stages of making. First, prepare the Ni/Al metal alloys from the reduction of Ni(II) and Al(III). Second, the process of removing Al (0) metal from Ni/Al metal mixtures to produce porous Ni, generally called Raney Ni (RaNi). The prepared RaNi characterize using P-XRD and N2 physisorption. X-ray diffraction results show typical nickel (0) diffraction patterns at 2 theta 44.5° (111), 51.8° (200), and 76.4° (220). The results of N2 physisorption on RaNi showed a surface area of ​​64 m2/g and a pore diameter of 6.13 nm. The hydrogenation reaction of glucose without adding hydrogen gas was carried out for 6 hours at 80 °C using isopropyl alcohol as a hydrogen source. The reaction products were analyzed using 1H-NMR by observing the proton chemical shift of the methine and methylene groups of sorbitol at 3.53-3.78 ppm and using the DNS (3-5, dinitrosalysilic acid) test to determine the remaining glucose in the solution. The reaction product tested using DNS showed that the amount of glucose converted was 54% when RaNi was synthetic as a catalyst.