(663e) 5-Hydroxymethylfuran and 2,5-Dimethylfuran Production From Banana Waste

5-Hydroxymethylfuran and 2,5-Dimethylfuran Production from Banana Waste

Andrés Felipe Sierra-Salazar¹, Andrés Torres-Conde², Ángela Adriana Ruiz-Colorado³

¹ afsierrasa@unal.edu.co, ² atorresc@unal.edu.co, ³aaruiz@unal.edu.co

Grupo de Bioprocesos y Flujos Reactivos

Facultad de Minas

Universidad Nacional de Colombia – Sede Medellín

Keywords: 2,5-dimethylfuran, 5-hydroxymethylfurfural, hydrolysis, hydrogenolysis, banana.

2,5-Dimethylfuran (DMF), C₆H₈O, has interesting chemical and physical properties: high energy density (31.5 MJ/L, compared to gasoline: 35.0 MJ/L, and ethanol: 23.0 MJ/L, (Tong, Ma, & Li, 2010)), high boiling point (20K higher than ethanol) and little solubility in water (Román-Leshkov, Barrett, Liu, & Dumesic, 2007). Indeed, DMF has the lowest water solubility and the highest research octane number (RON) among all the mono-oxygenated C6 compounds. These observations show the potential of DMF as an additive or alternative of transportation fuels (Tong et al., 2010).

DMF can be produced by 5-hydroxymethylfurfural (HMF) catalytic hydrogenolysis (Tong et al., 2010). As intermediate, 2,5-bis(hydroxymethyl)furan (BHF) is also produced. The latter can be used in the industry of polymers, resins and artificial fibers (Lewkowski, 2001).

Banana: source of hexoses

Just in Colombia, the surplus of banana production is around 120.000 tons per year, this biomass is then dropped. In other banana producer countries the surpluses of fruit also exist due to damage, inadequate maturity, overproduction, etc. About 70% of banana world exports are form Ecuador, Philippines, Costa Rica, and Colombia (Correa Uribe, 2011).

Banana fruit is primarily composed of starch and its peal, of cellulose. The shoot and pseudo-stalk (other wastes from banana culture) have also important amount of cellulose.  These compounds can be hydrolyzed to glucose. Traditionally, the sugary liquor produced by hydrolysis is usually fermented to ethanol (Correa Uribe, 2011). However, glucose monomers are hexoses that could be converted to HMF; an alternative of adding value to wastes and surplus in the banana production chain.

5-Hydroxymethylfurfural (HMF)

HMF can be obtained from hexoses, polysaccharides and industrial wastes. From hexoses, the occurring reaction is a triple dehydration. However, the obtaining of this compound is not an easy task because the HMF is an intermediate compound in the reaction from sugars to levunilic and formic acids. Also, there is the possibility that the HMF polymerize into humic acids at high concentrations (Lewkowski, 2001).

In addition, as stated before, the production of HMF is carried out through a dehydration process, which is more complex when it is considered that lignocellulosic residuals besides being composed by cellulose, hemicellulose and lignin, are materials rich in water (Lewkowski, 2001).  All these limitations open the door for an optimization development in the HMF production.

Experimental Procedure

The lignocellulosic material was homogenized by milling and mixing. Then, moisture was determined using the NREL method TP-510-42621: Determination of Total Solids in Biomass and Total Dissolved Solids in Liquid Process Samples (Sluiter et al., 2008).  After, the ratio dry-solid / liquid and acid concentration were adjusted for the hydrolysis. The reactions were carried out at 100rpm.

For the experimental design defined to optimize the production of HMF, three variables were selected to be handled: time, temperature and acid concentration. These have the biggest impact on the obtaining of HMF (Correa Uribe, 2011). Previous experiments were also carried out using these factors in a reduced factorial 3^3-1design. From that, the ranges of higher HMF concentrations were achieved without sulfuric acid, temperatures above 150°C and for about 4 hours (Sierra-Salazar & Ruiz-Colorado, n.d.).

Having those results on mind, the factors selected for acid, concentrations of 0.0 and 0.5 % w/w, for temperature 165°C and 210°C, for time were 2 and 4 hours, since with higher temperatures, the time is expected to be reduced. The chosen design was a response surface - central composite design unblocked with 20 experiments including 6 repetitions on the central point.

After the hydrolysis reaction, liquid extraction was performed in 4 successive stages with chloroform. Then, a small amount of high boiling point solvent was added to the organic phase in order to proceed with the evaporation of chloroform using vacuum rotary equipment. HMF was finally obtained in the desired solvent (Rufian-Henares, Garcia-Villanova, & Guerra-Hernandez, 2001).

The hydrogenolysis reaction to DMF was carried in two different solvent systems: water and water - n-butanol. The reaction conditions were: 20ml of medium volume, 0.4g of catalyst, 4.0bar as initial hydrogen pressure and 220°C for 10 hours (Román-Leshkov et al., 2007).

The catalysts for this reaction were copper supported on silica or on γ-alumina, with barium as a promoter in some trials. For their preparation, the incipient impregnation method was used (Guo, Zhou, Mao, Guo, & Zhang, 2009), which includes the deposition of the catalytic compounds (CuNO₃, BaNO₃) by dropping them in solution over the supporting material. The solvent for these solutions has to be chosen considering the wetting angle relative to the support, in order to be adsorbed onto the carrier surface (Yang, 2003).

After impregnation, the catalyst were dried for 12 hours at 110 ° C and thereafter calcined at 400 ° C for 3 hours and finally the catalyst was reduced in situin the reactor under the reaction conditions. The copper and barium ratio are 2.7mmol/g support and 0.3mmol/g support, respectively (Guo et al., 2009).

Results

HMF was detected by HPLC with PDA (SPD-M20A, Diode Array Detector) and levulinic acid with RID-10A (Refrective Index Detector), from Shimadzu. The conditions included a column: Aminex HPX-87H Bio-Rad, mobile phase H₂SO₄5mM at 60°C, 0.6ml/min and 20uL of injection volume.

After an ANOVA analysis, the maximum production of HMPF was found to be 3.08% g HMF / g initial biomass, keeping close to zero the concentration of levulinic acid. This value was obtained under the conditions of almost non sulfuric acid and around 190°C. For a scaling of the process, we recommend a series of reactors and between them, separation steps, in order to convert the maximum amount of biomass to 5-hydroxymethylfurfural.

For the conversion of HMF to DMF in water, four catalysts were used, two supported on commercial silica and two on alumina. The highest conversion was obtained with the supported on alumina (~ 100%) compared with copper on silica (96.7%) and mixture of copper and barium on silica (95.5%). For the production of DMF in a biphasic system (50% water – 50% n-butanol), the same catalysts were used and the conversion of HMF obtained with all of them was around 81%.

According to these results, Cu/Silica and Cu/γ-Alumina did not show significant differences in reactive conversions.

References

Correa Uribe, J. F. (2011). Identificación y modelamiento de la producción de furfural e HMF en el proceso de hidrólisis ácida de excedentes de la fruta de banano. Universidad Nacional de Colombia.

Guo, L., Zhou, J., Mao, J., Guo, X., & Zhang, S. (2009). Supported Cu catalysts for the selective hydrogenolysis of glycerol to propanediols. Applied Catalysis A: General, 367(1-2), 93–98. doi:10.1016/j.apcata.2009.07.040

Lewkowski, J. (2001). Synthesis , chemistry and applications of 5-hydroxymethylfurfural and its derivatives. Arkivoc, 2001(i), 17–54.

Román-Leshkov, Y., Barrett, C. J., Liu, Z. Y., & Dumesic, J. a. (2007). Production of dimethylfuran for liquid fuels from biomass-derived carbohydrates. Nature, 447(7147), 982–5. doi:10.1038/nature05923

Rufian-Henares, J. A., Garcia-Villanova, B., & Guerra-Hernandez, E. (2001). Determination of Furfural Compounds in Enteral Formula. Journal of Liquid Chromatography & Related Technologies, 24(19), 3049–3061. doi:10.1081/JLC-100107356

Sierra-Salazar, A. F., & Ruiz-Colorado, Á. A. (n.d.). 5-hydroxymethylfurfural and 2,5-dimethylfuran production from banana waste.

Sluiter, A., Hames, B., Hyman, D., Payne, C., Ruiz, R., Scarlata, C., Sluiter, J., et al. (2008). Determination of Total Solids in Biomass and Total Dissolved Solids in Liquid Process Samples Biomass and Total Dissolved Solids in Liquid Process Samples, (March).

Tong, X., Ma, Y., & Li, Y. (2010). Biomass into chemicals: Conversion of sugars to furan derivatives by catalytic processes. Applied Catalysis A: General, 385(1-2), 1–13. doi:10.1016/j.apcata.2010.06.049

Yang, R. T. (2003). Adsorbents fundamentals and applications. Chemical Engineering.