Levulinic Acid Production Using Solid-Acid Catalysis - Industrial

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Levulinic acid production using solid-acid catalysis Ilian Guzman, Arkaitz Heras, B. Güemez, A. Iriondo, J.F. Cambra, and J. Requies Ind. Eng. Chem. Res., Just Accepted Manuscript • DOI: 10.1021/acs.iecr.5b04190 • Publication Date (Web): 29 Mar 2016 Downloaded from http://pubs.acs.org on April 2, 2016

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Industrial & Engineering Chemistry Research

Levulinic acid production using solid-acid catalysis. Ilian Guzmán, Arkaitz Heras, M. B. Güemez, Aitziber Iriondo, Jose F. Cambra, Jesús Requies* Faculty of Engineering (UPV/EHU), Alameda Urquijo s/n, 48013 Bilbao, Spain phone.: +34 96 6017242, e-mail: [email protected]

Abstract. Levulinic acid (LA) is one of the compounds included in the list of the 12 chemicals, known as “building blocks” obtained from biomass. One route to synthesize levulinic acid is from furfuryl alcohol, compound that can be obtained from biomass. For this route it is necessary the furfuryl alcohol hydratation and its ring opening. Usually, the hydration takes place using homogeneous strong acid catalysts, being the disadvantages of using homogeneous acid catalysts well-known. Therefore, this work has studied the levulinic acid production using heterogenous catalysts such as ion exchange resins, zeolites and acidic clays. The LA yield increased by the optimal control of FA fed. The initial catalyst screening study showed results up to 62% in LA yield. Then, an optimization procedure was developed using the ZSM-5 catalyst, reaching a maximum LA yield of 77%. 1. Introduction The route to synthesize LA from FA is the hydratation and ring opening of FA [1-4]. The synthesis of levulinic acid (LA) from furfuryl alcohol (FA) has been studied since the mid-twentieth century, and the majority of studies have been patented by various authors [1-4]. But the scientific literature published is not abundant. Usually, the FA hydratation to LA takes place using homogeneous strong acid catalysts as sulphuric or hydrochloric acids [2, 4, 5]. The disadvantages of using homogeneous acid catalysts are well known: risk in handling, high toxicity, the need of special infrastructures for their use with the corresponding associated cost, high amounts of catalyst, and the difficulty of their separation and recovery. Therefore, promising studies about this reaction has been included using heterogeneous catalysts with adequate acidity and textural properties [3, 6, 7]. Catalysts such as ion exchange resins, zeolites and acidic clays are gaining importance to obtain high purity products. These process using heterogeneous catalysts, with an easier separation step of the catalyst from the reaction mixture and lower corrosion issues, minimize the need for additional work-up procedures and avoid the generation of large volumes of acid wastes. The best results obtained in homogeneous catalysis (Masatomi et al. (1971) [2]), showed a 93 mol% yield to LA using a semi-batch reactor with hydrochloric acid as catalyst and methyl ethyl ketone (MEK) as solvent to dilute the FA fed. Whilst in heterogeneous catalysis the best results were published by Redmond et al. (1956) [1], which reported a 55 mol% yield to LA, using Amberlite IR-120 as catalyst in a semibatch process, by addition of concentrate FA to water. In acidic aqueous medium, FA polymerizes to form alternate oligomeric products (scheme 1) [8-12]. The formation of oligomeric resins in the hydration reaction of FA cause not only low yields, but also

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generates some operational problems in the process. The oligomeration occurs via a condensation among the hydroxyl group of the methyl group of one furan ring and the hydrogen atom in the fifth position of another furan ring, leading to water elimination and formation of a methylene linkage [12]. An alternative to avoid or limit these undesired reactions is the control of the FA concentration in the reaction media, concentration below 2 % in weigh are recommended [8]. To achieve this low concentration of FA and limit the formation of undesirable by-products, an organic inert co-solvent may be added on the reaction media [8]. Scheme 1. Main reactions of furfuryl alcohol in aqueous acid medium

At high concentrations of FA, the polymerization reaction is the predominant one by the kinetic of the different reactions. Taejin Kim et al. [8] established that the FA polymerization is generated by the formation of a primary carbocation (-CH2+) from protonation of FA hydroxyl group. According to their hypothesis the presence of the solvent in reaction medium, can generate a competition with the carbocation of FA by interactions as solvation process, thus reducing the resin formation. Moreover, recently Otto et al. [13], suggested that solvent can affect the reaction rates through steric effects. Others authors also studied the aqueous reaction of FA, without report of yields to LA. Hronec et al. [6] found that major compound obtained was the 4-hydroxy-2cyclopentenone (4-HCP), when is catalyzed by hydrogen ions formed by autodissociation of water. Maldonado et al. [7], asserts that germinal diol species (4,5,5trihydroxypentan-2-one) were formed as main intermediate to LA by the use of AmberlystTM 15 as catalyst. In addition to this, some other authors have also studied the effect of using organic solvents to extract organic molecules from the aqueous acidic reaction medium and minimize the undesired condensation products using alkyl alcohols [14], alkyl phenols [15], cyclopentyl methyl ether [16] or traditional solvents as toluene or tetrahydrofuran [17], Furthermore, if an alcohol is incorporated in the FA acid reaction medium, then high yields to levulinate esters are obtained [18] Since the best result was reached by Masatomi et al. [2] using homogeneous catalysis, this work is focused on the study of the production of LA from FA by hydratation and ring opening of FA, using different heterogeneous acids catalysts as substitute of hydrochloric acid. Even more, a water soluble aliphatic ketone was added to the reaction media in order to obtain a higher efficiency in the production of LA. [2]. 2. Experimental. 2.1. Catalysts preparation The screening of catalyst was carried out preparing the following catalysts: inorganic catalysts as HZSM-5 zeolite (H-Z(50)), beta zeolite (HB), ultra stable zeolite (H-USY), heteropolyacid type phosphotungstic acid (PTA), zirconia sulphated superacid (ZrO2/SO42-), and the organic commercial ion exchange resins amberlyst 35 wet (A35) and amberlyst 47 (A47). These materials have a substantial amount of Brönstend acid sites [19-23], and different textural properties as surface area and pore size, as well as thermal stability. The ZSM5 (SiO2/Al2O3:50) and β zeolites (SiO2/Al2O3:25) were purchased from Zeolyst International (ammonia form).


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These were calcined at 823 K to their protonated forms H-Z(50) and H- β. The H-ZD (50) is the zeolite H-Z(50) which was subjected to desilication process using extraction of silica in a solution of NaOH (0.2 M) according to the following procedure: H-ZD (50) was added to NaOH (0.2 M) at 353 K and stirred for two hours. Then, the solids were separated by centrifugation and washed with bi-distilled water until neutral pH, afterwards these were dried overnight at 383 K. The obtained zeolites were also treated with NH4Cl (0.5 M) to 333 K; the samples were newly centrifuged and washed until all chlorides were eliminated; then the solid was dried to 383 K and subsequently calcined at 823 K during 4 h, to exchange NH4+ to H+. The superacid SO4-2/ZrO2 catalyst was synthesized by the precipitation method using an ultrasound system at low temperature according to the following procedure: ZrN2O7*H2O was dissolved in distilled water, then the pH was adjusted at 9.0 by the addition of aqueous ammonium (NH4OH, 30 %). The solution was introduced into ultrasound equipment, and it was dried at 383 K by 6 h. The dried solid was immersed in 50 mL of H2SO4(0.5M) by 12h, after this the solid was separated by filtration and was dried at 383 K. Finally, the solid was calcinated at 923 K. The hydrated phosphotungstic acid (PTA), (Alfa Aesar), was supported on ultra stable Y and ZSM5 zeolites (named as PTA-USY and PTA-Z(50) respectively). These materials were prepared containing 10 wt% of PTA (12WO3.H3PO4.xH2O), equivalent to 7.6 wt% tungsten; in both cases 0.3 grams of PTA were dissolved in bi-distilled water (50mL), the content was transferred to a rotary evaporator with 3 grams of zeolite previously degasified. The temperature of impregnation was set to 313 K, and 5 mbar. The solids obtained were calcined in air at 523 K. The amberlyst 47 (A47) and amberlyst 35 Wet (A35) are the commercial ion exchange resins provide by Rohm Haas. They were dried overnight to 333 K before use. 2.2. Characterization of catalysts Textural parameters were determined by N2 adsorption-desorption techniques at 77.35 K and the specific surface areas were obtained by applying BET method and the total pore volume was calculated at P/P0 = 0,976. Temperature-programmed desorption of ammonia (NH3-TPD) was used in order to measure the amount and strength of acid sites on the catalysts. The TPD profiles were monitored by TCD detector and recorded from 272 to 823 K at a heating rate 10 K/min. The catalyst was pretreated in a helium flow at 773 K for 1 h to remove the physisorbed water and the intra-crystalline water. Then, the sample was cooled to 373 K and then NH3 was adsorbed using pulsed injections at 373 K until saturation. The TCD signal was collected and processed to obtain the results. 2.2. Catalytic tests. For the activity tests a semibatch type reactor of 50 mL capacity (Parker-Autoclave Engineers), was used with a temperature and stirring controller (Iberfluid IB-50), and a liquid pump (Gilson 307). The reactor was loaded with 20 mL of a mixture which consisted of 4.2 ml of water (bidestilated) and 15.8 ml of the organic solvent. The organic solvents used were methyl ethyl ketone (MEK) (Alfa Aesar, 99 %), cyclopentyl methyl ether (CPME) (Sigma Aldrich, ≥ 99.90 %), tetrahydrofuran (THF) (Panreac, 99.5 %) and Acetone (Scharlau, 99.5 %). The selected quantity of



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catalyst was introduced in the reactor. Once the reactor was closed, it was purged with N2 gas and then the pressure was increased up to 10 bar using gas medium (N2 or H2). Finally, it was preheated to the desired temperature, and the pumping was started. A side solution consisting of organic solvent and FA (Sigma Aldrich, 98%) was pumped for 3.5 hours at 0.03 mL•min-1 of liquid flow. After this time, the pump was switched off and the time set in t=0. The test continued with heating and stirring on. Once finished the test, the product inside the reactor was filtered with 0.45 µm filters and weighted for later calculations. A sample was taken to be analyzed via gas chromatography in an Agilent 6890N GC with flame ionization (FID) and thermal conductivity (TCD) detectors. 3. Results and Discussion The results obtained in the preliminary screening are shown in Table 1. The high reactivity of FA can be observed, only the superacid catalyst did not reach a complete conversion of the FA, nevertheless the LA yield was very different. The higher LA yield, is corresponding with the lower carbon balance error. The main problem was the furanic resins formation (the presence of these furanic resins was confirmed due to the brown-black color of the reaction media), then their contribution in the carbon balances was not included. In addition there were some little peaks that were not identified in the GC-MS and therefore they were also not included in the carbon balance. In any case, for the best LA yields the mass balance error of the carbon balance was around a 20 %. In the preliminary results, it can be observed (Table 1) that under the conditions studied, the ion exchange resin A35 was the one showing the best performance attaining a LA yield up to 62 mol%, followed by H-Z(50) zeolite (58 mol%) and PTA-Z(50) (58 mol%). The catalysts properties are also summarized in Table 1, showing that the high acidity and mesoporosity of A35 influenced the increase of LA yield. The incorporation of PTA on Z(50) zeolite did not present improvements in the yield to LA respect to support. The modified zeolite H-ZD(50) do not showed differences in yield to LA respect to original support. In this case, although the desilication process caused a slight increase in pore diameter and surface area, the decrease in yield to LA can be related to the acidity loss. The activity results using H-β zeolite showed a low yield to LA, the surface characterization indicates that H-β has a high acidity, but a low pore diameter value, this property could affect the reaction mechanism related to the access of molecules to acid sites, causing the low yield to LA. Very low activity was also observed for the sulfated zirconium catalyst which showed the lowest FA conversion (59 mol%), without a relevant selectivity to LA, the low acidity value reported in Table 1 explains the inactivity of this catalyst in the reaction studied. According to the results obtained, the H-Z(50) zeolite, in its protonated form was selected to be used for optimization of operating parameters in the reaction system, as this catalyst has a better thermo mechanical stability than Amberlyst catalysts. Table 1 Properties of different solid acid catalysts studied and activity results obtained, Reaction conditions: 0.4 g of catalyst, 413 K, 10 bar of H2, MEK as solvent, 26.2 vol % FA in MEK, 1 h of


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reaction after 3.5 h flow fed. H-ZD(50): zeolite with a desilication process. SBET: surface area determined by BET method, dp: Average pore diameter. * Acidity in meq H+/g.

3.1 Optimization of operating parameters using H-ZSM5 zeolite (H-Z(50). The optimization consisted in the evaluation of the effect of the main operation conditions in the yield to LA. The variables that were considered for optimization comprised: use of hydrogen and nitrogen as atmospheres of reaction, the effect of solvent, effect of the amount of catalyst loaded, variation in the concentration of FA in the feed stream, and the effect of temperature. 3.2.1 Effect of the atmosphere of reaction. In the preliminary catalytic screening the reaction atmosphere was hydrogen. The first step in the optimization of operating parameters was the effect of the reaction atmosphere. For this propose the initial operating conditions chosen in the catalytic screening were 0.4 g of catalyst, 413 K, 10 bar of H2, MEK as solvent, 26.2 vol % FA in MEK, and 1 h of reaction. The reaction was studied under inert and hydrogenating atmospheres, excluding the oxidant atmosphere which is not suitable for this reaction due to the negative effect which causes by the formation of undesirable byproducts from furfuryl alcohol oxidation. In Figure 1, it can be observed that presence of hydrogen increased the LA yield in almost 20 mol%. This increment of the LA yield is related to the decrease of furanic polymers formation. The liquid obtained in the reaction media in the case of the inert atmosphere was darker that under hydrogenating atmosphere, indicating a higher amount of furan resins (polymers) in the case of the inert atmosphere. The polymers are formed on the catalytic surface continuously by partial polymerization of intermediate compounds formed from furfuryl alcohol. Furthermore, the different adsorption-desorption properties of reactant and products on the catalyst in different solvents [24] or reaction media [25] might potentially affect the product selectivity. In order to confirm the positive effect of hydrogen addition, an additional experiment was developed, increasing the hydrogen pressure from 20 to 50 bar and maintaining the other operating conditions. Under these set of conditions high differences in the conversion and the LA selectivity were not observed. The selectivity increased 0.5 mol% and the conversion decreased to 99.3 mol%, within the range of the experimental error. Therefore, the main conclusions of this part is that the combination of the solvent and H2 in the reaction media improved the LA yield. Nevertheless, there is a limit in the amount of hydrogen producing this beneficial effect. In addition, no hydrogenation products as 2-metylfuran (MF) or tetrahydrofurfuryl alcohol (THFA) were detected by GC (TCD-FID and MS) and HPLC, probably due to the absence of metals such as Ni, Cu, Ru, or Pt that favours the hydrogen adsorption on the catalysts surface and the corresponding hydrogenation reaction. Thus more



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research should be done in order to explain the exact role of the presence of hydrogen in this complex reaction system.

Figure 1. Effect of the atmosphere of reaction

3.2.2 Effect of solvent The use of solvent has a high importance in this reaction because its presence in the reaction media limits the resin formation, thus increasing the LA yield [4, 8]. The marked tendency of furan derivates to form resins has motivated studies on the incorporation of an organic co-solvent preventing in a great extent. This solvent, mainly different alcohols as ethanol, methanol, 2-propanol, reacts with FA to form the corresponding levulinate esther. In the case of the 5-hydmethylfurfural production from biomass, acetonritile, ethyl acetate, terahydrofuran and 2-butylphenol were used as solvents [26]. In the obtaining of furfural from xylosa solvents as dioxane, •valeroctone and tetrahydrofuran were also used [27]. The compounds with ketone group are also usually added as co-solvents. These include the methyl ethyl ketone and pentanone [2], in addition several authors reported the use of water soluble aliphatic ketone in the reaction media to obtain levulinic acid with high efficiency [2, 5]. As the aim of this work is LA production, alcohols were not used as solvent. For these work two cyclic structures as CPME and THF were chosen. The CPME is a green solvent with good properties in this type of process; while THF is a typical solvent in different biomass processes. Finally it was also chosen two linear ketone solvents as MEK and acetona were chosen, due to the high efficiency of the ketone as solvent in the levulinic acid production [2]. The results obtained are shown in Figure 2. The FA conversion in most cases was closer to 100 %, only the THF did not reach a complete conversion. The CPME is a hydrophobic solvent; therefore the presence of water and CPME produces a biphasic reaction system. The FA is dissolved in both phases, but FA is mostly located in the organic phase, so in the aqueous phase FA concentration remains quiet low. As the reaction occurs in aqueous phase, the FA gradually crosses to the aqueous phase through the interface to maintain the equilibrium. Using a biphasic reactor the LA yield was very low, 11 %, with total conversion. That could be related to the low FA concentration in the water phase, limiting the kinetics of the transformation of FA into furanic resins. The other solvents were soluble in water, the worst one was the THF. This finding was surprising because Dumesic et al [28] reached a high yield to LA using a similar ratio THF: WATER and the zeolite H-ZSM-5. These authors claim that the hydrophobic nature of H-ZSM-5 alter the internal solvent microenvironment within the zeolite framework, allowing for high levulinic acid yields, even at low THF solvent concentrations. Probably the presence of H2SO4 helped to maintain this internal solvent microenvironment to increase the levulinic acid yield. In present study it was observed that the presence of THF did not avoid the resins formation, therefore the yield was very low. The high yield obtained with MEK and acetone indicated that


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linear ketone group could act as an inhibitor of resin formation, since furan resins were not evidenced into reactor after reaction. The linear ketone group with higher molecular weight reached higher efficiency that acetone, it seems that the presence of this linear ketone avoided or limited the adsorption of the furanic resins on the catalytic surface increasing the levulinic acid yields.

Figure 2. Effect of the solvent in reaction media

3.2.3 Effect of the amount of catalyst loaded and variation in the concentration of FA in the feed stream LA yield as a function of FA concentration is shown in figure 3. in all cases the conversion of FA was 100 %. It can be appreciated an increase in yield to LA with a maximum value to 33.8 vol% of FA in MEK. After this value, a substantial decrease in yield is observed. Thus, low yield to LA at high concentration of FA could be attributed to the tendency of FA to form furan resin, according to the above referenced results. The low values in the concentration of FA fed, also exhibited low yields to LA, in this case attributed to the formation of 4-hydroxy-2-cyclopentenone (4-HCP) which is a byproduct of reaction from furfuryl alcohol. The formation of 4-HCP is favoured at low ratios of FA/H2O. The high range of variation of yield to LA shown in Figure 3, which represents up to 40 mol%, indicates that it is an important variable to be controlled in this process.The FA mol fed per gram of catalyst (mol FA/gcat) was also one parameter selected for the optimisation in semi-batch system using H-Z(50) as catalyst. The evolution of yields to LA with this parameter is shown also in Figure 3. The representation of results indicates that the yield increased with increasing the ratio mol FA/gcat, however, the yield was stable between values of 0.04 and 0.06. So that, the optimal FA concentration was defined as 33 vol% (Figure 3) and the quantity of catalysts was chosen as the average value between the two maximum points obtained in Figure 3, this value corresponds to 0.5 g of catalyst. Figure 3 Effect of the FA concentration and catalyst amount

3.2.4 Effect of temperature. Figure 4, shows the effect of temperature in the yield to LA. A slight decrease in the LA yield was observed when the temperature was increased in the range between 413 and 463 K, being more remarkable at 463 K. But, the differences only reached a variation up to 5 mol% in the yield to LA. Although the effect of temperature in yield to LA was insignificant in the range studied, the formation of some by-products was affected by such changes. This is the case of by-product as 4-HCP, which was formed mainly at low temperatures. On the other hand, the increase in temperature could favour the reaction of formation of furan resins as reported by some authors [6, 8]. Figure 4 Effect of the temperature in LA yield



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3.2.5 Effect of reaction time. The evolution of the LA yield was followed alongside the reaction time. Figure 5 shows the integrated signal intensity corresponding to the three main compounds identified in the reaction system: FA, LA and 4-HCP. As it can be seen, LA concentration keeps increasing even when the reactive FA is already not present. This confirms the existence of an intermediate compound in the reaction mixture which could not be detected in the gas chromatographic analysis (Figure 5). A maximum yield to LA was found at 23 h after stopping the feeding pump. This value corresponds to 77.7 mol% of yield to LA and 100 mol% of FA conversion (Figure 6). The differences in yield obtained between 1 h and 23 h of reaction reached up to 18 mol%. This little difference in yield compared to the long reaction time may not be economically feasible, therefore to avoid high energy consumption, a lower reaction time must be selected considering a slight loss in yield.

Figure 5 Effect of reaction time in the product distribution in the GC (FID signal) (Operation conditions: 0.5 g of H-ZSM5 catalyst, 413 K, 20 bar of H2, MEK as co-solvent, 36.8 %vol FA). Figure 6 Effect of the reaction time in the LA yield (Operation conditions: 0.5 g of H-ZSM5 catalyst, 413 K, 20 bar of H2, MEK as co-solvent, 36.8 %vol FA).

3.2.6. Recovery of the catalysts After the optimization of all of the catalytic parameters, the used catalyst was recovered and again calcined for its activation and it was named as H-ZR(50). This regenerated catalysts presented different structural characteristics and acidity than the fresh one (H-Z(50)). In the Table 1 it is summarized textural properties of the fresh and recycled catalyst. After the second calcination, the SBET decreased and the mesopore area also slightly decreased. Regarding the acidity, the recovered catalyst has lower total acidity. These two factors lower mesopority and lower acidity decreased the levulinic acid yield 12 mol % points (65 %) with a total conversion of FA. Nonetheless, the viability of recovery and recycling of the H-ZD (50) zeolite is positive, because the yield decreased but not too much, which is a factor very important related with the economical feasibility.

4. Conclusions After the screening of catalysts with inorganic structure, the H-ZSM5 zeolite showed higher yields to LA compared to other materials evaluated as heteropolyacids (PTA), super acids (zirconium sulfated) and other zeolites. An adequate porosity and acidity is the key of this higher LA yield.


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The reaction system was a semicontinuousreactor which allowed the increase of yield to LA, minimizing the formation of undesired furan resins, by the incorporation of MEK as solvent of FA in the feed. Also, the use of H2 atmosphere minimized the furanic resins formation, improving the LA yield. Optimisation of previous paramenters along the optimization of the other operation conditions as the ratio of FA fed to amount of catalyst and temperature of reaction increased the LA yield up to 77 mol% in 23 h of reaction after 3.5 h of FA feeding. Acknowledgements In memorial of Arkaitz Heras, you will always be alive in our minds. This work was supported by University of the Basque Country (UPV/EHU), European Union through the European Regional, Development Fund (FEDER) (Spanish MICIN Project: CTQ2012- 38204-C03-03), and the Basque Government (Researcher Training Programmer of the Department of Education, Universities and Research).

5. References [1] Redmond BC. Process for the production of levulinic acid. US Patent 1956; 2738367. [2] Masatomi ON, Yoshio HT, Kinoshita, Tokushima TM, Naruto J. Manufacture of Levulinic Acid. US 1971; 3.752.849. [3] W.D. Van de Graaf, J.P. Lange, Process for the conversion of Furfuryl Alcohol into Levulinic Acid or AlKyl Levulinate, US Patent 7.265.239B2 (2007) [4] B. Capai, G. LArtigau, Preparation of levulinic acid, US PAntent 5.175.358 (1992) [5] J.J. Bozell, L. Moens, D.C. Elliot, Y. Wang, G.G. Neuenschwander, S.W. Fitzpatrick, R.J. Bilski, J.L. Jarnefeld, Production of levulinic acid and use as a platform chemical derived products. Resour. Conserv. Recycling. 2000, 28 227-39 [6] M. Hronec, K. Fulajtárová, T. Soták, Kinetics of high temperatura conversión of furfuryl alcohol in water, J. Ind. Eng. Chem. 2014; 20; 650-55 [7] González Maldonado G, Assary R, Dumesic J, Curtiss L. Experimental and theoretical studies of the acid-catalyzed conversion of furfuryl alcohol to levulinic acid in aqueous solution. Energy Environ. Sci. 2012; 5: 6981-9. [8] Taejin Kim, Rajeev S. Assary, Hacksung Kim, Christopher L. Marshall, David J. Gosztola, Larry A. Curtiss, Peter C. Stair. Effects of solvent on the furfuryl alcohol polymerization reaction: UV Raman spectroscopy study. Catal. Today 2013; 205: 6066. [9] Kim T, Assary RS, Pauls RE, Marshall CL, Curtiss LA, Stair PC. Thermodynamics and reaction pathways of furfuryl alcohol oligomer formation. Catalysis Communications 2014; 46: 66-70. [10] Alimukhamedov MG, Magrupov FA. Kinetics of homopolycondensation of furfuryl alcohol. Polym. Sci., Ser. B 2007; 49: 1287-92.



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[11] Ssuer Chuang GE, Maciel GEM. Carbon-13 NMR study of curing in furfuryl alcohol resins. Macromolecules 1984; 17: 1087-90. [12] Krishnan TA, Chanda M. Kinetics of Polymerisation of Furfuryl Alcohol in Aqueous Solution. Die Angewandte Makromolekulare Chemie 1975; 43: 145-56. [13] Otto R, Brox J, Trippel S, Stei M, Best T, Wester R. Single solvent molecules can affect the dynamics of substitution reactions. Nat. Chem., 2012; 4(7):534-538 [14] Y. Roman-Leshkov, J.A. Dumesic, Solvent effects on fructose dehydratation to 5hydroxymethylfurfural in biphasic systems saturated with inorganic salts, Top. Cat. 52 (2009) 297-303 [15] D.M. Alonso, S.G. Wettstein, J.Q. Bond, J.A. Dumesic, reduction of Biofuels from cellulose and Corn Stover Using Alkylphenol Solvents, ChemSusChem 4 (2011) 107881. [16] M.J. Campos Molina R. Mariscal, M. Ojeda, M. López Granados, Cyclopentyl methyl ether: A green co-solvent for the selective dehydration of lignocellulosic pentoses to furfural, Bioresour. Technol. 126 (2012) 321-7 [17] J.J. Bozell, L. Moens, D.C. Elliot, Y. Wang, G.g: Neuenscwander, S.W. Fitzpatrick, R.J. Bilski, J.L. Jarnefeld, Poduction of levulinic acid and use as a platform chemical for derived products, Resour. Conserv. Recycling 28 (200) 227-39. [18] R.I. Khusnutdinov, A.R. Baiguzina, A.A. Smirnov, R.R. Muknimov, U.M. Dzhemilev, Furfuryl Alcohol in Shyntesis of Levulinic Acid Esters and Difuylmethane with Fe and Rh Complexes, Russ. J. Appl. Chem. 80 (2007) 1687-90 [19] A. Jentys, G. Warecka, J.A. Lercher, Surface chemistry of HZSM-5 studied by time-resolved IR spectroscopy, J. Mol. Catal. 51 (1989) 309-27 [20] D. Tzoulaki, A. Jentys, J. Pérez-Ramírez, K. Egeblad, J.A. Lercher, On the location, strength and accessibility of Bronsted acis sites in hierarchical ZSM-5 particles, Catal. Today 198 (2012) 3-11. [21] J.A. Van Bokhoven, Chapter 24- Strong Bronstyed Acidity in Aluminate-Silicates: Influence of Pore Dimesion, Steaming and Acid Site Density on Cracking of Alkanes, in: V. Valtchev, S. Mintova, M. Tsapatsis (Eds), Ordered orous Solids, Elsevier 1 (2009) 651-68 [22] A.G. Pelmenschikov, R.A. Van Santen, J.H.M.C. van Wolput, J. Jänchen, The IR transmission Windows of hydrogen bonbed complexes in zeolites: a new interpretation of IR data of acetronitrile and water on zeolitic Brönsted sites, Stud. Surf. Sci. Catal. 84 (1994) 2179-86 [23] C. Pereira, R.J. Gorte, Method for distinguishing Brönsted-acid sites in mixtures of H-ZSM-5, H-Y and silica-alumina, Appl. Catal. Gen. 90 (1992) 145-57. [24] Milan Hronec, Katarina Fulajtárova, Matej Micusik, Influence of furanic polymers on selectivity of furfural rearrangement to cyclopentanone, Appl. Catal. A Gen. 468 (2013) 426-31. [25] Dongxia Liu, Dmitry Zemlyanov, Tianpin Wu, Rodrigo J. Lobo-Lapidus, James A. Dumesic, Jeffrey T. Miller, Christopher L. Marshall, Deactivation mechanistic studies of copper chromite catalyst for selective hydrogenation of 2-furfuraldehyde, J. Catal., 2013; 299; 336-45 [26] B. Saha, M. MA. Omar, Advances in 5-HMF production from biomass in biphasic solvent, Green Chem. (2014) 16-24


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[27] M. Mellmer, C. Sener, J. Marcel, R. Gallo, J. Luterbacher, D.M. Alonso, J. Dumesic, Solvent effect in Acid-Catalyzed Biomass Conversion Reactions, Angew. Chem., Int. Ed., 53(2014) 11872-7 [28] M. A. Mellmer, _J. M. R. Gallo, D. Martin Alonso, J. A. Dumesic; Selective production of levulinic acid from furfuryl alcohol in THF solvent systems over HSM5, ACS Catal., 2015, 5, 3354-59

Table of Contents graphic



LA Yield FA Conversion

100 99

LA Yield / % FA Conversion / %

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 12 of 20

98

98 88

80 60

58

40

32

20

11

10

0 MEK

CPME THF Solvent


Acetone

Page 13 of 20

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47


Scheme 1. Main reactions of furfuryl alcohol in aqueous acid medium



Figure 1 Effect of the atmosphere of reaction

LA Yield Conversion

100 Conversion or Yield (%)

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

100

100

80 60 50

40

31

20 0 N2

H2


Page 14 of 20

Page 15 of 20

Figure 2. Effect of the solvent in reaction media

LA Yield FA Conversion

100 99

LA Yield / % FA Conversion / %

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


98

98 88

80 60

58

40

32

20

11

10

0 MEK

CPME THF Solvent


Acetone


Figure 3 Effect of the FA concentration and catalyst amount

100

80

80

70 LA Yield (%)

LA Yield (%)

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 16 of 20

60 40

60 50 40

20

30 0 10

20

30 40 FA ( vol %)

50

60

20 0,030 0,035 0,040 0,045 0,050 0,055 0,060 mol FA/gcat


Page 17 of 20

Figure 4 Effect of the temperature in the LA yield

80 70 LA Yield (%)

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


60 50 40 30 20 390 400 410 420 430 440 450 460 470 Temperature (K)



Figure 5 Effect of reaction time in the product distribution (Operation conditions: 0.5 g of H-ZSM5 catalyst, 413 K, 20 bar of H2, MEK as co-solvent, 36.8 %vol FA).

8 7

-3

Peak area x10 / pA

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

LA 4HCP FA

6 5 4 3 2 1 0 0

20

40

60 80 Time / min

100


120

Page 18 of 20

Page 19 of 20

Figure 6 Effect of the reaction time in the LA yield (Operation conditions: 0.5 g of HZSM5 catalyst, 413 K, 20 bar of H2, MEK as co-solvent, 36.8 %vol FA).

100 90 LA Yield (%)

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


80 70 60

0 0

16

18

20 22 Time (hours)


24

26


1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Catalyst A 47 A35 H-β PTA-USY H-Z(50) H-ZD(50) H-ZDR (50) PTA-Z(50) SO42-/ZrO2

Yield LA % 26.01 62.39 20.70 19.79 58.22 56.38 58.10 0.18

to

Conversion % 99.55 99.12 91.56 90.18 99.45 99.80 100.00 58.93

S BET (m2/g) 50 50 441 494 395 407 300 342 108

dp (Å) 240 300 6 20 24 37 42 25 34

Mesoporosity (%) 100 100 0 10 50 75 70 34 95

Page 20 of 20

Acidity (mmol NH3/g) >4.7* ≥5.2* 1.282 0.720 0.826 0.661 0.727 0.703 0.338

Table 1 Properties of different solid acid catalysts studied and activity results obtained, Reaction conditions: 0.4 g of catalyst, 413 K, 10 bar of H2, MEK as solvent, 26.2 vol % FA in MEK, 1 h of reaction after 3.5 h flow fed. H-ZD(50): zeolite with a desilication process. SBET: surface area determined by BET method, dp: Average pore diameter. * Acidity in meq H+/g.


Levulinic Acid Production Using Solid-Acid Catalysis - Industrial

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