Catalytic strategy for conversion of fructose to organic dyes, polymers, and liquid fuels

Abstract

We report a process to produce a versatile platform chemical from biomass-derived fructose for organic dye, polymer, and liquid fuel industries. An aldol-condensed chemical (HAH) is synthesized as a platform chemical from fructose by catalytic reactions in acetone/water solvent with non-noble metal catalysts (e.g., HCl, NaOH). Then, selective reactions (e.g., etherification, reduction, dimerization) of the functional groups, such as enone and hydroxyl groups, in the HAH molecule enable applications in organic dyes and polyether precursors. High yields of target products, such as 5-(hydroxymethyl) furfural (HMF) (85.9% from fructose) and HAH (86.3% from HMF) are achieved by sequential dehydration and aldol-condensation with a simple purification process (>99% HAH purity). The use of non-noble metal catalysts, the high yield of each reaction, and the simple purification of the target product allow for beneficial economics of the process. Techno-economic analysis indicates that the process produces HAH at minimum selling price (MSP) of $1958/ton. The MSP of HAH product allows the economic viability of applications in organic dye and polyether markets by replacing its counterparts, such as anthraquinone ($3200-$3900/ton) and bisphenol-A ($1360-$1720/ton).

Fig.1.

(A) Fructose conversion (Blue bar), HMF yield (Red bar), and HMF selectivity (Green dot) as a function of acetone ratio in the solvent (Reaction conditions: 0.6 g fructose (~420 mM) in 8 mL acetone/water solvent at 393 K over 0.2 g Amberlyst-15 catalyst), (B) Fructose conversion (Blue), HMF yield (Red), and Carbon balance (Black) as a function of reaction time (Reaction conditions: 19.6 wt% fructose in acetone/water (50/50, v/v) solvent with 137 mM HCl), (C) Fructose conversion (Blue), HMF yield (Red), and Carbon balance (Black) as a function of reaction time (Reaction conditions: 9.1 wt% fructose in acetone/water (75/25, v/v) solvent with 121 mM HCl), (D) Chemicals concentration in dehydrated solution before (Green bar) and after (Yellow bar) the decolorization (Decolorization conditions: 1.7 wt% activated carbon and 23 wt% water were mixed with dehydrated solution at 298 K for 30 min.

Fig.2.

Molar composition of HMF solution (feed for aldol-condensation) after the fructose dehydration, humin decolorization, and acetone distillation.

Fig.3.

Aldol-product yield (HAH: Light green bar, HA: Dark green bar) and fructose-derived HMF conversion (Red dot) as a function of $\frac{HMF}{Acetone+HA}$ (mol) ratio (Reaction conditions: 0.12 M (70 min), 0.23 M (60 min), 0.21 M (60 min) NaOH for $\frac{HMF}{Acetone+HA}$ (mol) = 2.0, 2.2, 2.5 at 308 K).

Fig.4.

(A) ¹³C quantitative NMR (qNMR) spectrum of purified, fructose-derived HAH (126 MHz, MeOD) δ: 190.49 (1C), 159.65 (2C), 152.51 (2C), 131.01 (2C), 123.42 (2C), 118.84 (2C), 111.42 (2C), 57.61 (2C) ppm, (B) ¹H standard NMR spectrum of purified, fructose-derived HAH (500 MHz, MeOD) δ: 7.51 (s, 1H), 7.48 (s, 1H), 6.98 (s, 1H), 6.95 (s, 1H), 6.82 (d, 2H), 6.47 (d, 2H), 4.58 (s, 4H) ppm (MeOD: 4.87 (s) ppm).

Fig.5.

(A) UV-vis absorption spectrum of diluted HAH (Green), HAH dimer (Red), and etherified HAH (Blue) in methanol solvent. (i) (2-hydroxymethyl furan) and (ii) (1,4-pentadien-3-one) represent the chromophores of HAH. (B) Molar excitation coefficient (slope, M⁻¹cm⁻¹) of diluted fructose-derived HAH in methanol solvent at 378 nm UV incident light.

Fig.6.

Overview of the process block-flow diagram to produce HAH from fructose.

Fig.7.

Breakdown of the costs and revenue of the proposed approach.

Scheme 1.

Overall catalytic reaction route for HAH production from fructose by dehydration and aldol-condensation.

Scheme 2.

Reaction mechanism of (A) HAH etherification with methanol over WO_x-ZrO₂ catalyst, (B) HAH selective reduction in presence of NaBH₄, and (C) HAH dimerization with acetate anion.