Conversion of d-Fructose to 5-(Hydroxymethyl)furfural: Evaluating Batch and Continuous Flow Conditions by Design of Experiments and In-Line FTIR Monitoring

Abstract

The dehydration reaction of d-(−)-fructose into 5-(hydroxymethyl)­furfural (HMF) in both batch and continuous flow conditions was comprehensively studied using the statistical tool design of experiments (DoE), employing i-PrOH/DMSO as the solvent system in the presence of the solid acid catalyst Amberlyst-15. Initially, screening of different alcohols (MeOH, EtOH, i-PrOH, and t-BuOH) showed that i-PrOH provides better selectivity and yield compared to the other alcohols, along with minimum formation of byproducts when associated with small amounts of DMSO (15% v/v) as a cosolvent. To confirm the selectivity of the reaction, all of the possible byproducts (HMF-ethers and/or ketals) formed during the reaction between HMF and i-PrOH were synthesized. Factors like temperature, amount of DMSO, time (flow rate), and catalyst loading were evaluated by a full factorial design, and the results indicated that temperature presents the greatest influence in both batch (HMF in 71% yield) and continuous flow regime (HMF in 95% yield). In addition, a FTIR device was coupled to the continuous flow micro reactor, allowing for the first time constant in-line monitoring for this transformation, thereby showing the long-term stability of Amberlyst-15 and process robustness.

Catalytic Transformation of Biomass Derivatives to Value‐Added Chemicals and Fuels in Continuous Flow Microreactors

“…Several researches focused on the heterogeneously catalyzed dehydration of fructose to HMF (derivatives) in single phase operation (Table 4, entries [12][13][14], [227][228][229] or xylose to furfural in biphasic flow (Table 4, entries [15][16] [230,231] using milli-scale packed bed reactors (d C = 4-10 mm). These millireactors could be easily transferred into microreactor configurations and thus give valuable insights in the potential of the latter for the heterogeneous synthesis of furans from sugars.…”

“…H 3 BO 3 (combined with NaCl) is an alternative homogeneous catalyst for the synthesis of HMF. [227,228] Above that, HMF ethers have a better storage stability than HMF, which can be advantageous as compared to using HMF as a substrate in the industrial production towards HMF derivatives (e. g., FDCA). However, relatively low reaction rates (40-50 % HMF yield in 45 min at 150°C) were obtained with this catalyst in biphasic batch reactors.…”

Isomerization Kinetics of Glucose to Fructose in Aqueous Solution with Magnesium‐Aluminum Hydrotalcites

“…For instance, Galaverna et al. reported that Amberlyst‐15 was a highly efficient catalyst for fructose conversion to HMF in continuous flow conditions with a yield of 95.00 % . Our previous studies have reported sulfonated hierarchical porous carbons and SBA‐15 supported niobium phosphate (Nb−P/SBA‐15) are also very effective for converting fructose to HMF, with HMF yields more than 92.00 % .…”

Continuous Production of 5‐Hydroxymethylfurfural from Monosaccharide over Zirconium Phosphates

“…Galaverna et al . synthesized HMF from fructose in both batch and continuous flow conditions by employing i ‐PrOH/DMSO as solvent system in the presence of Amberlyst‐15 . And HMF was effectively produced from fructose and glucose using phosphate buffer saline (reaction phase)/2‐ sec ‐butyl phenol (extraction phase) biphasic reaction system in a microreactor by Muranaka and co‐workers .…”

“…[8] Galaverna et al synthesized HMF from fructose in both batch and continuous flow conditions by employing i-PrOH/DMSO as solvent system in the presence of Amberlyst-15. [9] And HMF was effectively produced from fructose and glucose using phosphate buffer saline (reaction phase)/2-sec-butyl phenol (extraction phase) biphasic reaction system in a microreactor by Muranaka and co-workers. [10] Moreover, acidic metal phosphates were shown to be effective for conversion of monosaccharides into HMF, due to its acidity, structure superiorities with large surface areas and large pores, high thermal stability, allowing its possible recovery and reuse in recent years.…”