Direct Transformation of Glycerol to Propanal using Zirconium Phosphate‐Supported Bimetallic Catalysts

Abstract

Selective transformation of glycerol to propanal (PA) provides a feasible route towards the sustainable synthesis of high valueadded chemicals. In this work, zirconium phosphate (ZrP) was studied as support and Ru and Co as metal sites for glycerol hydrogenolysis in a continuous-flow reactor. It was found that ZrP-supported CoÀ O species had a moderate selectivity to PA (49.5 %) in glycerol hydrogenolysis. Notably, once Ru species were doped into CoO/ZrP, the resulting catalyst exhibited not only an outstanding catalytic performance for glycerol hydrogenolysis to PA (a selectivity of 80.2 % at full conversion), but also a high stability at least a 50 h long-term performance. The spent catalyst could be regenerated by calcining in air to remove carbonaceous deposits. Characterization indicated that the acid sites on ZrP played a very critical role in the dehydration of glycerol into acrolein (AE), that the distribution of Co was uniform, basically consistent with that of Zr, P and Ru, and that an especially close contact between CoÀ O and Ru species was formed on Ru/CoO/ZrP catalyst. The further activity tests and characterizations confirmed that there was a strong interaction between the dispersed CoÀ O species and Ru 0 nanoparticles, which endowed Ru sites with high electronic density. This effect could play a role in facilitating the dissociation of H 2 , and thus in promoting the hydrogenation reaction. Besides, DFT calculations suggested that the CoÀ O species can adsorb more strongly the C=C bond of the intermediate AE on a highly coordinatively unsaturated Co (Co cus) site and thus lead to preferential hydrogenation at the C=C bond of AE to PA.

A Cationic Ru(II) Complex Intercalated into Zirconium Phosphate Layers Catalyzes Selective Hydrogenation via Heterolytic Hydrogen Activation

“…In contrast to the Ru foil, Ru-phen, Ru-ZrP_0.4, and Ru/α-ZrP displayed higher "white lines", indicating they had higher chemical state than Ru foil (Ru 0 ), agreeing with XPS results (Figure S4 and S6). [73] For Ru-phen, the strong peak at approximately 1.8 Å was attributed to RuÀ Cl coordination shell, while the major peak at 1.5 Å of Ru-ZrP_0.4 catalyst was related to RuÀ O shell (the enlarged region in Figure 8a), [74,75] which revealed that most of chloride ligands in Ru-phen have been substituted by the layer's phosphate groups in the course of intercalation reaction, being consistent with the results of 31 P MAS NMR (Figure 3). In the EXAFS spectra of Ru/α-ZrP, two major peaks centered around 1.5 Å and 1.8 Å respectively related to RuÀ O and RuÀ Cl coordination shells were also observed, indicating that only a small amount of Ruphen complex could also intercalate into ZrP layer even without exfoliation (with RuÀ O and RuÀ Cl shell) (Figure 8a).…”

The Promotional Effect of Sulfates on TiO2 Supported Pt‐WOx Catalyst for Hydrogenolysis of Glycerol

“…[1][2][3] The renewability and unique structure of glycerol make it a versatile platform molecule for producing a variety of fine chemicals via catalytic reactions, such as hydrogenolysis, oxidation, dehydration, esterification and others. [4][5][6][7][8] 1,3-propanediol (1,3-PDO) is an important chemical from glycerol hydrogenolysis with wide applications in the manufacture of polytrimethylene terephthalate, polyurethanes, and cyclic compounds. [9,10] n-Propanol (n-PO) is another valuable derivative from glycerol and is widely used as a solvent, pharmaceutical or pesticide intermediate.…”

“…[9,10] n-Propanol (n-PO) is another valuable derivative from glycerol and is widely used as a solvent, pharmaceutical or pesticide intermediate. [8] The current market price of glycerol hydrogenolysis products ranks from high to low as 1,3-PDO > n-PO > 1,2-PDO. [11] Thus, the direct hydrogenolysis of glycerol into n-PO has also attracted much attention recently.…”

“…Glycerol is available as a byproduct in surplus amounts owing to the rapid growing of biodiesel production, and thus requires efficient transformation to value‐added chemicals [1–3] . The renewability and unique structure of glycerol make it a versatile platform molecule for producing a variety of fine chemicals via catalytic reactions, such as hydrogenolysis, oxidation, dehydration, esterification and others [4–8] . 1,3‐propanediol (1,3‐PDO) is an important chemical from glycerol hydrogenolysis with wide applications in the manufacture of polytrimethylene terephthalate, polyurethanes, and cyclic compounds [9,10] .…”

“…1,3‐propanediol (1,3‐PDO) is an important chemical from glycerol hydrogenolysis with wide applications in the manufacture of polytrimethylene terephthalate, polyurethanes, and cyclic compounds [9,10] . n‐Propanol (n‐PO) is another valuable derivative from glycerol and is widely used as a solvent, pharmaceutical or pesticide intermediate [8] . The current market price of glycerol hydrogenolysis products ranks from high to low as 1,3‐PDO>n‐PO>1,2‐PDO [11] .…”