MgO‐ZrO₂ Mixed Oxides as Effective and Reusable Base Catalysts for Glucose Isomerization into Fructose in Aqueous Media

Abstract

MgO-ZrO 2 mixed oxides prepared with different Mg/Zr atomic ratios (denoted as xMZ:w here x is the atomic ratio of Mg/Zr)are investigated for the glucose isomerization to fructose in water at 95 8C. The highest fructose yield of 33 %i so btained over 0.76MZ with % 74 %s electivity after 3h.T og ain insighti nto the structure-activity relationships, the prepared catalysts are characterizedb yN 2 physisorption, XRD, FTIR and CO 2 -TPD. The results indicate that the addition of MgO drastically changed the textual property of ZrO 2 and increased the number of basic sites. The kinetic studies revealed that the Lewis basic sites (cus-O 2À )g enerated from the highly dispersed MgO are the active sites responsible for the enhanced isomerization activity.N otably, MZ is reusable for four runs without as ignificant decrease in catalysta ctivity.A ccordingly,t his study provides an easily prepared, cheap,a nd recyclable catalystt hat may hold great potential for fructose production.[a] Dr.A .I.M.R abee, S.

High Selective Isomerization of Glucose to Fructose Catalyzed by Amidoximed Polyacrylonitrile

“…However, metal leaching was still a matter in those catalytic system, which made the catalysts irreversible and influence quality of products. − Basic metal oxide was more stable in aqueous solution. The catalytic activity of natural MgO, crab-shell/MgO, and MgO–ZrO 2 hardly decreased within several recycled times, and the yield of fructose reached 29–33 with 70–74% selectivity. − Fixed amine is another potential catalyst for isomerization of glucose to fructose. Deshpande tuned and loaded the tertiary amine group to SiO 2 as a heterogeneous catalyst and achieved 37% conversion of glucose with 70% selectivity similar to triethylamine .…”

Aerobic Oxidation of 5-Hydroxymethylfurfural into 2,5-Furandicarboxylic Acid over Gold Stabilized on Zirconia-Based Supports

“…Afterward, 2 M NaOH solution was slowly added until the pH value of the mixture reached 10.5 under vigorous stirring. The precipitate yielded was further aged at room temperature for 24 h in the mother liquid, then filtered and washed extensively with distilled water (12 L) . The obtained solid was dried at 110 °C for 12 h, and then calcined at 400 and 600 °C at the heating rate of 2 °C min –1 for 4 h in static air in an oven (KDF 3000 Plus).…”

Revealing the contributions of homogeneous and heterogeneous catalysis to isomerization of d-glucose into d-fructose in the presence of basic salts with low solubility

“…15 Solid bases 16 and solid Lewis acids 17 exhibit comparable catalytic activity for the isomerization though the Lewis acids catalyze co-formation of D-mannose in somewhat higher amounts. A broad range of solid bases exhibit catalytic activity for the isomerization, which includes MgO 14,18,19 and other alkaline earth metal (hydr)oxides, 20 MgO-doped ordered mesoporous carbon, 21 Mg-Al hydrotalcites, 14,15,18,[22][23][24][25][26][27][28][29][30] Mg-or Ca-impregnated or exchanged zeolites, [31][32][33][34][35] attapulgite, 36,37 MgO-Nb phosphate, 38 Mg-doped carbon nitride, 39 Mg-containing titanosilicates, 40 CaO-ZrO 2 , 41 MgO-ZrO 2 , 42 MgO/biochar, 43 CaO-Al 2 O 3 , 44 CaO-MgO, 45 CaO/ C, 46 alkaline earth metal titanates, 47 soluble amines [48][49][50][51][52][53][54][55]…”