Selective hydrodeoxygenation of biomass derived 5-hydroxymethylfurfural over silica supported iridium catalysts

Abstract

Catalytic performance of iridium supported on SiO2 was investigated for 5hydroxymethylfurfural (HMF) transformation. Ir/SiO2 catalysts exhibiting different metal loading (1, 3, and 5 wt.%) were tested in the preliminary experiments in the hydrogenation of two probe molecules, e.g. ethyl pyruvate (EP) and ketopantolactone (KP) to evaluate the Ir dispersion on the catalyst activity in C=O hydrogenation. In the transformation of HMF the influence of metal dispersion, iridium precursor and addition of H2SO4 were studied revealing that 2,5-bis-(hydroxymethyl)furan (BHMF) was the main product with 83% selectivity at 70% conversion of HMF over chlorine free Ir/SiO2 together with H2SO4 at 333 K in THF under 10 bar hydrogen. On the other hand, one-pot synthesis of HMF to 2,5dimethylfuran (DMF) was promoted in the presence of chlorine containing Ir/SiO2(Cl) and H2SO4. Both of these products are considered high value-added chemicals from biomassderived 5-hydroxymethylfurfural. The exposed iridium atoms together with the total acid sites are an important catalytic descriptor for hydrogenation of HMF to BHMF.

Efficient Electrochemical Hydrogenation of 5‐Hydroxymethylfurfural to 2,5‐Bis(hydroxymethyl)furan on Ag‐Displaced Nanotextured Cu Catalysts

“…2,5‐Bis(hydroxymethyl)furan (BHMF) is a reduced derivative of HMF that can be used as a precursor for the syntheses of many biobased polymers, including polyurethanes, polyethers, and polyamides . BHMF is currently obtained by the hydrogenation of HMF at high pressures (8–65 bar) of H 2 in the presence of heterogeneous catalysts, including Au/Al 2 O 3 , Pt/MCM‐41, Ir/TiO 2 , Ir/SiO 2 , and Ir−ReO x /SiO 2 . However, H 2 is a high‐cost hydrogen donor, and conventional HMF hydrogenation systems mostly suffer from low utilization ratios of H 2 .…”

Synthesis of carbon-supported bimetallic palladium–iridium catalysts by microemulsion: characterization and electrocatalytic properties

“…[51] and Ir/γ-Al 2 O 3 [52,53]. These states were observed at 61.1 and 62.8 eV in series of Ir/SiO 2 [54]. In the 5% Ir/C catalyst, Date et al [55] observed three components of the Ir 4f 7/2 peak ascribed to the metallic Ir°(60.9 eV) and oxidized species IrO 2 (61.5 eV) as well as IrO 3 (62.21 eV).…”

Separation procedures in the identification of the hydrogenation products of biomass-derived hydroxymethylfurfural

“…Performing the mass spectrometry allowed to compare the mass spectral patterns (m/z) of the compounds in the reaction mixture. The most intense peaks in the mass spectrum (notably m/z: 97 and 126 for HMF, 128 and 97 for BHMF, 56 and 41 for DMTHF, 96 and 95 for DMF) allowed to identify HMF and the reaction products [41]. Analytics was as well established in detail way in the work of Gyngazova et al [50].…”

“…When it comes to the subject of this review, the product identification efficiency depends on many factors, of which one of the most important is the selectivity of HMF hydrodeoxygenation reaction and therefore the number of products to analyze, and their difference in volatility. There are some limited examples where only one GC detector was used for analysis (FID) [38,39] and for selective reactions with the presence of only a few products (HMF, DMF, BHMF, 5-MFA) without many impurities it proved fully sufficient, practically allowing to close the carbon balance of the reaction [40][41][42]. However, where a wide range of by-products is present, FID is often combined with MS detector or NMR spectroscopy analysis, which allow the structure confirmation [42][43][44][45][46][47][48] and therefore more complete detection.…”

“…This combined technique allows to nearly fully identify and quantify all reaction products [40,46,49]. An interesting example of analysis is described in the work of Chimentão et al [41] with the use of GC-MS equipped with a β-dex column containing permethylated β-cyclodextrin embedded in an intermediate-polarity stationary phase. Those types of phases are recommended for analysis of chiral compounds like ketones, alkanes, alkenes, alcohols, acids, ethers, etc.…”