Promotional Role of Surface Defects on Carbon‐Supported Ruthenium‐Based Catalysts in the Transfer Hydrogenation of Furfural

Abstract

The synthesis of highly efficient supported metal catalysts is of vital importance for the modern development of the production of chemicals. In this regard, biomass‐based chemical transformation holds potential promise through many heterogeneous catalytic processes. Herein, we report surface defect engineering on a carbon‐supported, Ru‐based catalyst by a two‐step hybridization–self‐reduction route, which involves the assembly of a hybrid composite of ternary Co‐Al‐Ru layered double hydroxide (CoAlRu‐LDH) and amorphous carbon through the carbonization of glucose and a subsequent in situ self‐reduction process. The results revealed that Ru3+ species in the resulting CoAlRu‐LDH‐C composite could be reduced in situ to Ru0 species by the carbon component in the hybrid composite, and Co‐containing spinels with a large quantity of surface oxygen vacancies could be formed simultaneously on the surface. The as‐fabricated Ru‐based catalyst showed a superior catalytic performance in the liquid‐phase transfer hydrogenation of furfural to furfuryl alcohol using benzyl alcohol as hydrogen donator to other Ru‐based catalysts derived from LDH‐C composite precursors. It was proven that surface defects (i.e., oxygen vacancies, Co2+ species) could enable the chemisorption of furfural spatially and ensure the activation of its carbonyl groups, which promoted the transfer hydrogenation greatly.

Metal Catalysts for the Efficient Transformation of Biomass‐derived HMF and Furfural to Value Added Chemicals

“…Gao et al. explored Ru‐based bimetallic catalysts, Co‐Ru/C, Zn‐Ru/C, Ni‐Ru/C, and Mg‐Ru/C for the transfer hydrogenation of furfural to furfuryl alcohol using benzyl alcohol as both hydrogen donor and solvent . Among all studied catalysts, Co‐Ru/C exhibited superior catalytic activity and resulted in 98 % yield of furfuryl alcohol in 12 h. The in situ FT‐IR analysis for the adsorption of furfural on the surface of metal catalyst revealed a strong vibration at 1671 cm −1 , attributed to the interaction of carbonyl group with metal catalyst surface, and a weak vibration at 1721 cm −1 for the stretching vibration of C=O bond in the physisorption of furfural.…”

“…To wards the upgradationoffurans, monometallic and bimetallic Ru based catalysts have also shown high efficacy towards the hydrogenation of furans. [113,[115][116][117][118][119][120][121][122][123] Nagpuree tal. explored hydrogenolysis of HMF to DMFo ver Ru containing hydrotalcite(HT) catalysts and achieved complete conversion of HMF to DMF at 220 8Ci n4h.…”

Catalytic Transfer Hydrogenation of Biomass‐Derived Substrates to Value‐Added Chemicals on Dual‐Function Catalysts: Opportunities and Challenges

“…Generally, it is believed that noble metals can promote hydrogen spillover; thus the CTH reaction can be enhanced, although control of the extent of hydrogenation still remains a great challenge. Bimetallic catalysts with both C−H and C=C cleavage functionalities have attracted extensive attention, examples of which include PtRe, PdNi, CuPd, CuNi, and CoRu catalysts ,…”

Kinetics of Furfural Hydrogenation over Bimetallic Overlayer Catalysts and the Effect of Oxygen Vacancy Concentration on Product Selectivity

“…[18] The critical role of oxygen vacancies in RuO 2 -catalyzed furfural transfer hydrogenolysis via a reverse Mars-van Krevelen mechanism is also demonstrated. [19][20] Apart from deoxygenation reactions, oxygen vacancies are also believed to facilitate the C=C double bond hydrogenation reactions. [21][22][23][24][25] Although the importance of oxygen vacancies in hydrodeoxygenation of phenolic compounds has been well elucidated, the effect of oxygen vacancies in furfural hydrogenation is not much studied, especially considering that furfural and phenolic compounds share much structural resemblance.…”