Liquid phase glucose hydrogenation to d-glucitol over an ultrafine Ru-B amorphous alloy catalyst

Ultrasound-assisted synthesis of monodisperse Ru–B amorphous alloys with enhanced catalytic activity in maltose hydrogenation

“…2 show that both the Ru-B-C and all Ru-B-x samples synthesized via the present method (e.g. Ru-B-60) were present in typical amorphous alloy structure, because only one broad peak centered at 2h = 44°was observed [14][15][16][17], as demonstrated by Yokoyama et al [23]. The amorphous alloy structure can be further confirmed by a successive diffraction halo in an attached SAED image [24].…”

“…The enhanced intrinsic activity of ruthenium had also been confirmed by comparing the activities of Ru-and Ni-based catalysts in the hydrogenation of glucose [14,15] and/or fructose [33,34]. On the other hand, the superior intrinsic activity of the as-prepared catalysts could be attributed to their unique amorphous alloy structure, which had proven to be favorable for hydrogenation processes [8][9][10][11][12][13][14][15][16][17][18]. This could be supported by the fact that an abrupt decrease in activity was observed for the Ru-B-60 treated at 873 K for 2 h in Ar flow (Table 1), which was firstly due to the significant agglomeration of Ru-B nanoparticles at elevated temperatures and, thus, decreasing S act and, secondly, the decrease in R H S resulted from the crystallization and decomposition of Ru-B amorphous alloy.…”

“…Although Raney Ni had the highest S act , it still exhibited much lower R H m and maltose conversion within 3 h than all of the Ru-B amorphous alloy catalysts because of its lowest intrinsic activity (R H S ), suggesting that Ru was much more active than Ni in nature for maltose hydrogenation. The enhanced intrinsic activity of ruthenium had also been confirmed by comparing the activities of Ru-and Ni-based catalysts in the hydrogenation of glucose [14,15] and/or fructose [33,34]. On the other hand, the superior intrinsic activity of the as-prepared catalysts could be attributed to their unique amorphous alloy structure, which had proven to be favorable for hydrogenation processes [8][9][10][11][12][13][14][15][16][17][18].…”

“…The as-prepared Ru-B samples were designated as Ru-B-x, where x represents the ultrasound power. For comparison, a conventional Ru-B sample was also prepared by the regular method, i.e., by direct reduction of RuCl 3 with KBH 4 [14][15][16][17], which was denoted as Ru-B-C. Raney Ni catalyst was provided by Aldrich Chemical Co. and used without further treatment.…”

Experimental and theoretical studies on glucose hydrogenation to produce sorbitol

“…Usually, hydrogenation is carried out using supported nickel catalysts. The Raney-Ni type catalyst has been employed in this process due to its high activity and low cost [4]. However, ruthenium catalysts present higher activity than nickel in the hydrogenation of glucose in aqueous solutions [5].…”