Effects of Water Addition to Isopropanol for Hydrogenation of Compounds Derived from 5-Hydroxymethyl Furfural over Pd, Ru, and Cu Catalysts

Abstract

We have developed lumped reaction schemes to optimize the yields of products from selective hydrogenations of HAH, a biomass-derived platform chemical produced by two-step aldol condensations of 5-hydroxymethyl furfural (H) with acetone (A). Reaction schemes consisting of 7, 9, and 11 steps were examined to describe the rates of formation of the observed products and reaction intermediates for hydrogenation of HAH over Ru and Pd catalysts, and a 3-step scheme was studied over Cu catalysts. Rate constants and activation energies were calculated using these reaction schemes, and we then apply the schemes to explore the effects of water addition on the hydrogenation pathways. The effects of water addition to isopropanol (IPA) solvents on the hydrogenation of HAH were markedly different over Pd, Ru, and Cu catalysts. Over the Pd catalyst, the addition of water to IPA increased hydrogenation rates and promoted the hydrogenation of furan rings. The addition of water to IPA yielded significant carbon losses over the Ru catalyst, and slowed hydrogenation steps over Cu, while significantly inhibiting hydrogenation of the ketone group. This behavior opened routes toward increased production rates of PHAHO (a partially hydrogenated, P, form of HAH containing a CO bond), a product in which the diene groups of the furan rings were not hydrogenated. The addition of water also allowed increased feed concentrations of HAH that were previously not possible in pure IPA solvents. The insights presented in this work provide a more mechanistic description of the hydrogenation of HAH, the behavior of specific intermediates, and the reactivity of key functional groups.

Design of supported organocatalysts from a biomass-derived difuran compound and catalytic assessment for lactose hydrolysis

“…The product was characterized by 1 H and 13 C NMR and was quantified by GC-FID. 21 2.3 Synthesis of GA-MAL by imidation 3.22 g (33 mmol) of maleic anhydride and 4.81 g (33 mmol) of L-glutamic acid were added into 31.5 g of acetic acid solvent in a 200 mL-scale round-bottom flask. The round flask was placed in an oil bath, set at 170 °C, with reflux and reacted for 120 min under the stirring (600 rpm).…”

“…The unassigned chemical shifts in 13 C NMR spectrum of PHAH-GA-MAL (Fig. S14 †) resulted from PHAH 21 and GA-MAL (Fig. S13 †), formed by retro Diels-Alder reaction during evaporation of THF solvent at 40 °C.…”

“…Therefore, the furan moiety in HAH must be activated for Diels-Alder reaction by selective hydrogenation of the enone group. After the enone group in HAH has been selectively hydrogenated, 21 the partially hydrogenated HAH (PHAH) can be used as a monomer for the synthesis of Diels-Alder adducts that can be used to design performance-advantaged plastics. 22 Enzymes are used in dairy [23][24][25] and biorefinery applications 26 because of their superior activity and selectivity for desired chemical reactions.…”

Oxygen Vacancy-Reinforced Water-Assisted Proton Hopping for Enhanced Catalytic Hydrogenation

“…Catalytic hydrogenation on metal oxide-supported nanoparticles is the highly followed standard industrial protocol for the production of both fine and bulk chemicals. − In general, the diffusion of hydrogen atoms across the surface of the metal oxide-supported catalyst is crucial to the hydrogenation because the diffusion can increase the concentration of active H-atoms on the metal oxide surface during the hydrogenation. − Therefore, it significantly affects the catalytic performance of metal oxide-supported catalysts. − Generally, on the surface of a metal oxide, the diffusion of H-atoms has to overcome a high energy barrier (55–236 kJ mol –1 ), , while on the surface of a noble metal, the energy barrier for dissociation of H 2 or the diffusion of H-atom is almost negligible . Fortunately, water can assist H-atom diffusion across the oxide surface, also known as water-assisted proton hopping (WAPH), via the classic proton coupling electron mechanism. , Specifically, water picks up H-atoms to form a short-lived transition state of hydronium ions (H 3 O + ), accompanied by electron transfer from the H-atom to the d orbital of the metal oxides, which can promote the hydrogenation over metal oxide-supported catalysts. − For example, Zhao et al reported that furfural hydrogenation on the Pd/Al 2 O 3 catalyst was accelerated by replacing the cyclohexane solvent with water.…”

Synthesis of Alumina Supported Pt-SnO2 Hybrid Nanostructures by In Situ Transformation of PtSn Alloy Nanoparticles and Their Application as Highly Efficient Catalysts for Selective Hydrogenation of Furfural

“…The serious environmental pollution caused by Cu–Cr catalysts requires the development of chromium-free catalysts. In the literature, various transition metal-based catalysts have been reported for hydrogenation of furfural, including Ni, ,− Co, , Cu, ,− Ru, Pd, , and Pt, , where a second metal or promoter is sometimes added to increase catalytic activity and/or selectivity.…”