New Method for Highly Efficient Conversion of Biomass-Derived

Research Article pubs.acs.org/journal/ascecg

New Method for Highly Efficient Conversion of Biomass-Derived Levulinic Acid to γ‑Valerolactone in Water without Precious Metal Catalysts Heng Zhong,†,# Qiuju Li,‡,# Jianke Liu,‡ Guodong Yao,§ Jie Wang,§ Xu Zeng,‡ Zhibao Huo,§ and Fangming Jin*,§ †

Research Institute for Chemical Process Technology, National Institute of Advanced Industrial Science and Technology, Nigatake 4-2-1, Sendai, 983-8551, Japan ‡ College of Environmental Science & Engineering, Tongji University, 1239 Siping RD, Shanghai, 200092, China § School of Environmental Science and Engineering, State Key Lab of Metal Matrix Composites, Shanghai Jiao Tong University, 800 Dongchuan RD, Shanghai 200240, China S Supporting Information *

ABSTRACT: γ-Valerolactone (GVL) is receiving increasing attention because of its significant characteristics of an ideal sustainable liquid fuel. In this work, a novel and nonprecious metal catalytic method of the hydrogenation of biomass-derived levulinic acid (LA) into GVL by water splitting is first reported. Commercially available nonprecious metals of Fe, Ni, Cu, Cr, and Mo exhibited significantly catalytic activities in the hydrogenation of LA into GVL. Over 90% yield of GVL from LA can be obtained at a relatively low temperature of 180 °C, and an excellent 98% yield of GVL was achieved over the Fe catalyst at 250 °C. Catalyst Fe is stable and still keeps the high catalytic activity after recycles. The extraordinary catalytic activity of the general Fe powder is probably because of the role of hot water and also a synergistic role of the Fe and ZnO or Zn/ZnO. Also, the reactor wall of a reactor made of the stainless steel material acted as a significant catalyst, and a considerably high GVL yield of 56% can be obtained even without any addition of catalyst. This method is simple, highly efficient, and requires neither gaseous hydrogen nor precious metal catalyst, which is key for the practical application. KEYWORDS: Biofuel, Bioresource, Biomass conversion, Green energy, Sustainable, Water hydrogen

■

additive or a precursor for advanced green fuels.9−14 This colorless liquid (GVL) has low melting (−31 °C), high boiling (207 °C) and open cup flash (96 °C) points, which is easy and safe to store and move globally in large quantities.15 The GVL can also be used to produce a variety of compounds including butene, valeric acid, and 5-nonanone as well as a solvent derived from biomass.16 On the other hand, LA is a typical biomass-derived platform chemical, which can be readily produced from the cellulose and lignocellulose that abundantly contained in the terrestrial plants. Thus, the production of GVL from LA has a great potential in the conversion of renewable

INTRODUCTION

Over consumption of fossil fuels together with its impact on the environment in terms of greenhouse gas emission highlight the need of exploring renewable and green energy sources.1,2 Although renewable energies, such as solar, wind, and tidal can provide almost zero CO2 emission, their abilities to produce future transportation fuels with high energy density and organic chemicals that traditionally derived from the crude oils are rather limited. Thus, it is strongly desired to exploit carbonneutral energy resources, such as biofuels produced from renewable biomass, to substitute the fossil fuels and to achieve a sustainable development.3−8 Recently, the production of γvalerolactone (GVL), a stable and low-toxic liquid organic, from the biomass-derived levulinic acid (LA) has received extensive research interests because of its wide application in food and perfume industry as well as its potential use as a fuel © 2017 American Chemical Society

Received: February 28, 2017 Revised: May 15, 2017 Published: June 12, 2017 6517

DOI: 10.1021/acssuschemeng.7b00623 ACS Sustainable Chem. Eng. 2017, 5, 6517−6523

Research Article

ACS Sustainable Chemistry & Engineering

out of the oven and was cooled to room temperature with an electric fan. The reaction time was defined as the time that the reactor was placed in the oven at the desired temperature. The liquid product was collected and filtered through a 0.22-μm filter membrane. The solid samples were collected, washed with deionized water several times to remove impurities, and dried in vacuum at 40 °C for 24 h. Fe catalyst after the reaction was recovered by separating from ZnO in the precipitate through a magnetic process for six times and then washed with ethanol for six times under sonication. To investigate the wall effect of a stainless steel reactor, a SUS316 batch reactor was used, which was constructed of a piece of SUS316 tube (3/8 in. diameter, 1 mm wall thickness and 120 mm length) with an internal volume of 5.7 mL. The experimental procedure was conducted as follows. Two mL of an aqueous solution of LA and desired amount of Zn were loaded into the reactor. The reactor was sealed and immersed in a salt bath preheated to the desired temperature. The reaction was terminated by placing the reactor into a cold water bath. The reaction mixture was collected and filtered through a 0.22-μm syringe filter for further analyses. Analytic Method. Liquid samples were analyzed by a GC-FID (Agilent 7890) equipped with an HP Innowax polyethylene glycol capillary column with dimensions of 30 m × 250 μm × 0.25 μm. The sample analysis was confirmed by GC-MS equipped with an HPInnowax capillary column of 30 m length, 0.25 mm of internal diameter, and a film thickness of 0.15 μm. Solid samples were analyzed by X-ray diffraction (XRD, Bruker D8 Advance X-ray Diffractometer) equipped with a Cu Kα radiation to determine the composition and phase purity. The quantitative analysis of the compositions of the solid sample was determined by TOPAS 4.2 from Bruker AXS, US. SEM images of the solid samples were obtained with a scanning electron microscopy (SEM, Hitachi S-4800) operating at 15 kV. The yield of GVL is defined as the molar ratio of the produced GVL to the initial LA. The yield of ZnO is defined as the molar ratio of the produced ZnO to the initial Zn.

biomass resources into chemical fuels and feedstocks to substitute the fossil fuels. In current research of the hydrogenation of LA to GVL, homogeneous or heterogeneous catalysts are generally employed to improve the conversion of LA and selectivity of GVL, and most of these catalysts involve precious metals, such as Ru, Pt, Pd and Au.17−21 Moreover, high-pressure molecular hydrogen is normally used as the hydrogen source for the GVL production from LA in the traditional hydrogenation, which involves some problems such as the hydrogen transportation and storage. Therefore, seeking for a novel, efficient and simple process with facile hydrogen for the hydrogenation of GVL to LA is necessary. Application of hydrothermal reactions to biomass conversion is receiving increasing attention because of the unique inherent properties of high-temperature water (HTW) that include a high ion product (Kw) and a low dielectric constant, which are favorable for promoting reactions without catalysts.22 We have previously demonstrated the availability of hydrothermal conversion of biomass into several value-added chemicals, such as formic acid, acetic acid, lactic acid, and levulinic acid, based on the oxidation conversion of the biomass resources.23 Moreover, there have been some reports of the hydrogenation of biomass or biomass-derived chemicals into fuels or valueadded chemicals under hydrothermal conditions.24,25 However, the hydrogenation of biomass or biomass-derived chemicals with water as both hydrogen source and medium under hydrothermal conditions is relatively limited. Recently, we studied the hydrogenation of CO2 under hydrothermal conditions and found that high-temperature water can be applied as an effective hydrogen source with commercially available and earth-abundant zero-valent metals, such as Zn, Fe and Al, as both reductants and catalysts.26,27 The in situ generated hydrogen from the reaction of HTW with zero-valent metals demonstrated much higher activity in the hydrogenation of CO2 than normal high-pressure gaseous hydrogen.28 These previous research suggest us that the hydrogenation of LA to GVL by using water as both hydrogen source and medium under hydrothermal conditions has a high potential for an efficient and selective conversion without using any precious metal catalyst. Thus, we proposed a new method for the synthesis of GVL from LA with the HTW-derived hydrogen using the earth-abundant metals (Zn, Fe, etc.) as the reductants and catalysts. To the best of our knowledge, it is the first time to report highly efficiently hydrogenation of LA to GVL by using the water as both hydrogen source and reaction medium without the use of any precious metal catalysts.

■

■

RESULTS AND DISCUSSION Conversion of LA to GVL without the Addition of Catalyst. Initially, a series of experiments were conducted to identify the feasibility of synthesizing GVL from LA in water with Zn as a reductant in the absence of catalysts. Figure 1a and b shows the effect of the reaction temperature and time on the yield of GVL. The results revealed that the formation of GVL was obviously observed even without the addition of any catalyst. The yield of GVL increased with the increase in the reaction temperature and time. It is generally known that a catalyst is indispensable in the hydrogenation of LA to GVL. The observed fact that GVL can be formed from LA without the addition of any catalyst suggests that some components may play a catalytic role in reducing the LA into GVL. As discussed later, the possible catalytic components probably involve in ZnO or Zn/ZnO complexes formed from the oxidation of Zn in HTW. The quantitative evaluation of the composition of the solid samples after the reactions by XRD analysis showed that the oxidation of Zn is strongly dependent on the reaction time and temperature (Figure 1c), thus, an increase in the yield of GVL with increasing reaction time and temperature is probably attributed to the enhancement of the oxidation of Zn in water or the hydrogen production from water. To further examine the effect of the hydrogen amount on the conversion of LA into GVL, the amount of initial Zn was investigated because Zn is used for producing hydrogen from water. As shown in Figure 2, both of the yield of GVL and the conversion of LA increased with the increase in the amount of Zn. When the addition of Zn was 40 mmol, the yield of GVL reached 28%. These results further indicate that the increasing

EXPERIMENTAL SECTION

Chemicals. Levulinic acid (LA, 99.8%, Sigma-Aldrich), Zn, Fe, Cr, Mo, and Ni (200 mesh, analytical grade (AR), Sino-pharm Chemical Reagent Co., Ltd.), were used without further purification. Standard LA (1 N standard solution) and γ-valerolactone (GVL, 98%) were purchased from Alfa Aesar and used as standards for the qualitative analysis of the products in the liquid samples. Experimental Procedure. Most of the experiments were conducted in a Teflon-lined stainless steel batch reactor with an inner volume of 28 mL. The experimental procedure is briefly described below: the desired amount of LA (10 g/L, 86 mmol/L) and Zn were added into the reactor with a water filling of 25% (7 mL). When necessary, metal catalysts, such as Fe, Ni, and Cu, were also loaded together with the reactants into the reactor. Then the reactor was sealed and placed into an oven that had been preheated to the desired temperature. At desired reaction time, the reactor was taken 6518


Research Article


Figure 2. Effect of Zn amount on the yield of GVL (LA = 86 mmol/L; temperature = 250 °C; time = 150 min).

reagent ZnO and collected ZnO after the reaction of Zn in HTW after a long reaction time of 420 min were used as the ZnO additives, while the solid samples after the reaction of Zn in HTW after short reaction times of 240 and 40 min were used as the Zn/ZnO complex additives. The XRD analyses showed that the mass ratio of Zn:ZnO was 1/16 for the sample at 240 min and 1/4 for the sample at 40 min, respectively (Figure S2). As shown in Table 1, no significant change in GVL yield was Table 1. Effect of Zn Additives on the Yield of GVL from LA with Gaseous Hydrogen as the Reductanta additives

yield of GVL (%)

none ZnOb ZnOc Zn/ZnOd Zn/ZnOe

1.0 1.3 1.8 9.8 14.9

a

Experiments were conducted in SUS316 reactor; temperature = 250 °C; time = 120 min; H2 = 3.2 MPa; catalysts (ZnO, Zn/ZnO) = 0.5 g. b Commercial reagent ZnO. cCollected ZnO after the reaction of Zn in HTW at 250 °C for 420 min. dFreshly produced Zn/ZnO complex (w/w = 1/16) from Zn in HTW at 250 °C for 240 min. eFreshly produced Zn/ZnO complex (w/w = 1/4) from Zn in HTW at 250 °C for 40 min.

observed when adding the reagent ZnO and collected ZnO. However, the yield of GVL was effectively improved with the addition of Zn/ZnO complex. These results suggest that the Zn/ZnO complex from the oxidation of Zn with HTW acts as a catalyst in the hydrogenation of LA to GVL, which may involve the formation of abundant defects in the Zn/ZnO complex and lead to easy adsorption of hydrogen. Conversion of LA to GVL with Nonprecious Metal Catalysts. Although the GVL could be produced from LA with Zn and HTW without any catalysts, the yield of GVL was not high. To further increase the yield of GVL, some nonprecious metals having the potential catalytic activity for hydrogenation reaction, such as Fe, Ni, Cu, Cr, and Mo, were examined. As shown in Table 2, both the yield of GVL and the conversion of LA significantly increased in the presence of these metals, particularly with Fe, Ni, and Cu. In the case of without the addition of any catalyst, the yield of GVL was only 12.1%; however, when Fe, Ni or Cu was added, the yield of GVL drastically ascended to 96.5%, 93.0%, and 92.0%, respectively.

Figure 1. Yield of GVL (a), conversion of LA (b) and yield of ZnO (c) as a function of reaction time at various temperatures (LA = 86 mmol/ L; Zn = 21 mmol).

hydrogen amount is advantageous for the conversion of LA into GVL. Also, as discussed later, increasing ZnO or Zn/ZnO due to the increase in the initial Zn might be one explanation for increasing the yield of GVL. In addition to GVL, other products in liquid samples were also analyzed, and the major byproducts were low molecular weight carboxylic acids such as acetic acid, propionic acid, isobutyric acid, pentanoic acid and 2-pentenoic acid, as well as 3-hydroxy-2-butanone (Figure S1). To study the catalytic role of the formed ZnO or Zn/ZnO complexes, experiments were conducted with gaseous hydrogen in the presence of ZnO or Zn/ZnO complexes. Commercial 6519


Research Article

ACS Sustainable Chemistry & Engineering Table 2. Effect of Different Metals as Catalysts on the Yield of GVLa catalyst

yield of GVL (%)

conversion of LA (%)

selectivity of GVL (%)

none Fe Ni Cu Cr Mo

12.1 96.5 93.0 92.0 42.7 59.2

25.0 98.8 99.7 93.9 56.2 84.2

48.4 97.7 93.3 98.0 76.0 70.3

Reaction conditions: LA = 86 mmol/L; temperature = 250 °C; time = 150 min; Zn = 21 mmol; catalysts (Fe, Ni, Cu, Cr, Mo) = 0.5 g.

a

XRD analysis of the solid samples after the reactions showed that Fe, Ni, Cu, Mo, and Cr remained in the zero-valent state, while Zn was completely converted to ZnO (Figure S3), indicating that these metals play a catalyst role in the hydrogenation of LA into GVL. Considering that Fe has a high catalytic activity in the tested catalysts and that the Fe is one of the most abundant metallic elements in the earth’s crust and can be easily and cheaply obtained, the production of GVL from LA in the presence of Fe was further investigated to examine reaction characteristics of the hydrogenation of LA into GVL and the parameters design for the high yield of GVL. The investigation of the effect of Fe amount showed that the yield of GVL and the conversion of LA greatly increased with an increase in the amount of Fe, and the highest yield of GVL of 98% was obtained with a Fe addition of 0.5 g (Figure 3a). Figure 3b shows the effect of reaction temperature and time on the yield of GVL, and interestingly, a high GVL yield of above 90% can be achieved even at a temperature as low as 180 °C within a much shorter time of 90 min compared to those without the addition of Fe. To examine the stability and recyclability of Fe catalyst, the Fe catalyst after the reaction was recovered and reused, and the results showed that the yield of GVL only slightly decreased from 90% to 83% after being recycled for 4 times at 180 °C (Figure 4). XRD analysis of the solid samples after each recycles indicated that the Fe still existed in zero-valent states (Figure S4). In the SEM images of the solid samples after the reactions, the Fe particles and hexagonal wurtzite ZnO crystal were clearly observed (Figure S5). The surface morphology of the Fe catalyst did not obviously changed while the particle size slightly decreased after the reaction, which is probably due to

Figure 4. Effect of the Fe recycle time on the yield of GVL (LA = 86 mmol/L; Zn = 21 mmol; temperature = 180 °C; water filling = 25%; time = 90 min).

the hydrothermal reaction. These results suggest that the Fe catalyst is relatively stable in the conversion of LA to GVL. Since Zn is oxidized to ZnO after the reaction, the regeneration of Zn from ZnO is needed for a sustainable production of GVL from biomass-derived LA. It has been reported that a 90% conversion of ZnO to Zn can be achieved with solar energy in a novel solar chemical reactor.29−32 Thus, the whole process would be sustainable by combining the reduction of ZnO to Zn with solar energy and the hydrothermal conversion of LA to GVL with Zn through a Zn−ZnO cycle. It should be noted that the conversion of Zn was ∼86% in the absence of any catalyst at 250 °C for 150 min as shown in Figure 1c. However, in the presence of the metal catalysts, as mentioned above, almost all the Zn converted to ZnO within the same reaction time, suggesting that the existence of these metals improves the oxidation of Zn. To further investigate the promoting role of Fe for the oxidation of Zn, the oxidation of Zn was examined in the presence and absence of Fe. The results showed that no significant change in the yield of ZnO/ conversion of Zn was observed when LA or Fe was solely added (Figure S6). Interestingly, the yield of ZnO greatly increased with the addition of both Fe and LA. The yield of ZnO reached up to about 75% for a short reaction time of 10 min, and to nearly 100% for 40 min. The enhancement of Zn oxidation in water with Fe is probably because the formation of tiny Zn/Fe galvanic cells described by the following electrode reactions:

Figure 3. Effect of Fe amount (a), reaction time and temperature (b) on the yield of GVL (LA = 86 mmol/L; Zn = 21 mmol; (a) temperature = 250 °C; time = 150 min; (b) Fe = 0.34 g). 6520


Research Article


Catalytic Activity of the Stainless Steel Reactor Wall. Experiments were all conducted in a Teflon-lined reactor in the basal study to avoid the effect of stainless steel reactor wall. On the other hand, the stainless steel reactors are commonly used in the industrial production. The element Fe contained in the stainless steel reactor would probably benefit the formation of GVL from LA. Therefore, the GVL production with a SUS-316 reactor instead of the Teflon reactor was conducted without the addition of any catalyst to examine catalytic activity of the stainless steel wall. As illustrated in Figure 6, a relatively high GVL yield of 56% was obtained, which is much higher than the highest yield of GVL (only 12%) with the Teflon reactor without the addition of catalyst. These results suggest that the catalytic activity of the SUS316 reactor wall is significant in the conversion of LA into GVL. Thus, the conversion of LA into GVL can be more readily and economically performed with only Zn as a reductant with the stainless steel reactor, which is advantageous to the practical application. Proposed Reaction Mechanism of Conversion of LA into GVL. On the basis of the attained results, a possible mechanism of the hydrogenation of LA to GVL with Zn in HTW was proposed in Scheme 1. First, hydrogen is formed via the oxidation of Zn in HTW. The in situ formed hydrogen is adsorbed on the surface of the metal catalyst (M), such as Fe, Ni, and Cu. Moreover, considering the fact that (1) GVL could be formed from LA in the Teflon reactor with only Zn without the addition of any metal catalysts, such as Fe, Ni, or Cu, (2) our previous research has demonstrated that the active intermediate structure of hydride is zinc hydride (Zn−H) in the reduction of CO2 with Zn as a reductant in HTW,28,33 and (3) in the presence of Fe catalyst, the decrease in the particle size of ZnO and the formation of nano ZnO rod were clearly observed (see Figure 5 and Figure S7), namely, the interface of Zn/ZnO increased, the hydrogen formed from water is absorbed on the Zn/ZnO complex. In the meantime, the γcarbonyl (CO) of LA is adsorbed on the surface of M. Then, the activated hydrogen attacks the carbon of the CO adsorbed on the surface of M, and the double bond is reduced. Finally, the formed O− attacks the carbon of carboxyl (COOH) with the leaving of hydroxyl and GVL is formed with H2O.

Zn is oxidized to ZnO in HTW, acting as an anode to release electrons, while Fe acts as an inert electrode and transfers the electrons to H+ to form H2. LA provides the supporting electrolyte. Thus, the formation of a complete galvanic cell system between Zn and Fe enhances the oxidation of Zn in HTW. On the other hand, the solid residues after the reactions with or without Fe catalyst at different reaction times were further investigated by the SEM analysis. As shown in Figure 5,

Figure 5. SEM images of the solid samples after the reaction with (c, d) or without (a, b) Fe catalyst. (Reaction conditions: LA = 86 mmol/ L, Fe = 0 or 0.5 g, Zn = 21 mmol, temperature = 250 °C, water filling = 25%, time = 150 min.)

only relatively large particles of ZnO were generated in the samples without the Fe catalyst. However, nanorod-like ZnO was formed in the presence of Fe. Increasing the reaction time can obtain better crystallized ZnO no matter with or without Fe (Figure S7, Figure 5). Thus, these results (galvanic reaction and SEM analysis) suggest that the addition of Fe catalyst can not only effectively promote the oxidation of Zn to ZnO but also can decrease the particle size of ZnO to form nano ZnO rod, which synergistically increase the interface of Zn/ZnO and then promote the yield of GVL from LA.

■

CONCLUSIONS

A new process for conversion of the LA to GVL with Zn as a reductant in HTW has been developed. Metal catalysts, such as

Figure 6. Effect of reaction time (a) and Zn amount (b) on the yield of GVL in SUS316 reactor (LA = 86 mmol/L; temperature = 250 °C; (a) Zn = 6 mmol; (b) time = 120 min). 6521


Research Article


Scheme 1. Proposed Mechanism of Synthesis of γ-Valerolactone from Levulinic Acid with Zn as the Reductanta

a

M represents the metal catalysts of Fe, Ni, Cu, Mo, and Cr. (5) Ragauskas, A. J.; Williams, C. K.; Davison, B. H.; Britovsek, G.; Cairney, J.; Eckert, C. A.; Frederick, W. J., Jr; Hallett, J. P.; Leak, D. J.; Liotta, C. L. The path forward for biofuels and biomaterials. Science 2006, 311, 484−489. (6) Hassan, H.; Lim, J. K.; Hameed, B. H. Recent progress on biomass co-pyrolysis conversion into high-quality bio-oil. Bioresour. Technol. 2016, 221, 645−655. (7) Biddy, M. J.; Davis, R.; Humbird, D.; Tao, L.; Dowe, N.; Guarnieri, M. T.; Linger, J. G.; Karp, E. M.; Salvachua, D.; Vardon, D. R.; Beckham, G. T. The Techno-Economic Basis for Coproduct Manufacturing To Enable Hydrocarbon Fuel Production from Lignocellulosic Biomass. ACS Sustainable Chem. Eng. 2016, 4, 3196− 3211. (8) Lin, H.; Strull, J.; Liu, Y.; Karmiol, Z.; Plank, K.; Miller, G.; Guo, Z.; Yang, L. High yield production of levulinic acid by catalytic partial oxidation of cellulose in aqueous media. Energy Environ. Sci. 2012, 5, 9773−9777. (9) Horváth, I. T.; Mehdi, H.; Fábos, V.; Boda, L.; Mika, L. T. γValerolactonea sustainable liquid for energy and carbon-based chemicals. Green Chem. 2008, 10, 238−242. (10) Omoruyi, U.; Page, S.; Hallett, J.; Miller, P. W. Homogeneous Catalyzed Reactions of Levulinic Acid: To -Valerolactone and Beyond. ChemSusChem 2016, 9, 2037−2047. (11) Zhang, J.; Chen, J. Z.; Guo, Y. Y.; Chen, L. M. Effective Upgrade of Levulinic Acid into gamma-Valerolactone over an Inexpensive and Magnetic Catalyst Derived from Hydrotalcite Precursor. ACS Sustainable Chem. Eng. 2015, 3, 1708−1714. (12) Amenuvor, G.; Makhubela, B. C. E.; Darkwa, J. Efficient Solvent-Free Hydrogenation of Levulinic Acid to gamma-Valerolactone by Pyrazolylphosphite and Pyrazolylphosphinite Ruthenium(II) Complexes. ACS Sustainable Chem. Eng. 2016, 4, 6010−6018. (13) Xie, C.; Song, J. L.; Zhou, B. W.; Hu, J. Y.; Zhang, Z. R.; Zhang, P.; Jiang, Z. W.; Han, B. X. Porous Hafnium Phosphonate: Novel Heterogeneous Catalyst for Conversion of Levulinic Acid and Esters into gamma-Valerolactone. ACS Sustainable Chem. Eng. 2016, 4, 6231−6236. (14) Wright, W. R. H.; Palkovits, R. Development of Heterogeneous Catalysts for the Conversion of Levulinic Acid to gammaValerolactone. ChemSusChem 2012, 5, 1657−1667. (15) Horvath, I. T.; Mehdi, H.; Fabos, V.; Boda, L.; Mika, L. T. γValerolactone-a sustainable liquid for energy and carbon-based chemicals. Green Chem. 2008, 10, 238−242. (16) Alonso, D. M.; Wettstein, S. G.; Dumesic, J. A. γ-valerolactone, a sustainable platform molecule derived from lignocellulosic biomass. Green Chem. 2013, 15, 584−595. (17) Du, X. L.; He, L.; Zhao, S.; Liu, Y. M.; Cao, Y.; He, H. Y.; Fan, K. N. Hydrogen-Independent Reductive Transformation of Carbohydrate Biomass into γ-Valerolactone and Pyrrolidone Derivatives with Supported Gold Catalysts. Angew. Chem., Int. Ed. 2011, 50, 7815− 7819. (18) Bourne, R. A.; Stevens, J. G.; Ke, J.; Poliakoff, M. Maximising opportunities in supercritical chemistry: the continuous conversion of

Fe, Ni, and Cu, exhibited a high catalytic activity, and a 98% yield of GVL from LA was achieved at 250 °C. Also, a considerably high GVL yield of 56% can be obtained in SUS316 reactor without any addition of catalyst, which is the key to the practical application. These results are significant for the development of a simple and effective process for the production of GVL from biomass-derived LA or even directly from biomass.

■

ASSOCIATED CONTENT

S Supporting Information *

The Supporting Information is available free of charge on the ACS Publications website at DOI: 10.1021/acssuschemeng.7b00623. GC-MS data of the liquid sample, XRD and SEM results of the solid samples, and yield of ZnO data (PDF)

■

AUTHOR INFORMATION

Corresponding Author

*Tel/Fax: +86-21-54742283. E-mail: [email protected]. ORCID

Fangming Jin: 0000-0001-9028-8818 Author Contributions #

H.Z. and Q.L. contributed equally to this work.

Notes

The authors declare no competing financial interest.

■

ACKNOWLEDGMENTS The authors gratefully acknowledge the financial support from the State Key Program of National Natural Science Foundation of China (No. 21436007), the National Natural Science Foundation of China (No. 21277091 and 51472159), and Key Basic Research Projects of Science and Technology Commission of Shanghai (No.14JC1403100).

■

REFERENCES

(1) Chow, L. C. H. China’s Energy Future: A Framing Comment. Eurasian Geography and Economics 2011, 52, 523−528. (2) Hermann, B.; Blok, K.; Patel, M. Producing bio-based bulk chemicals using industrial biotechnology saves energy and combats climate change. Environ. Sci. Technol. 2007, 41, 7915−7921. (3) Goto, M.; Obuchi, R.; Hirose, T.; Sakaki, T.; Shibata, M. Hydrothermal conversion of municipal organic waste into resources. Bioresour. Technol. 2004, 93, 279−284. (4) Gallezot, P. Conversion of biomass to selected chemical products. Chem. Soc. Rev. 2012, 41, 1538−1558. 6522


Research Article

ACS Sustainable Chemistry & Engineering levulinic acid to γ-valerolactone in CO2. Chem. Commun. 2007, 4632− 4634. (19) Deng, L.; Zhao, Y.; Li, J.; Fu, Y.; Liao, B.; Guo, Q.-X. Conversion of Levulinic Acid and Formic Acid into γ-Valerolactone over Heterogeneous Catalysts. ChemSusChem 2010, 3, 1172−1175. (20) Yan, Z.; Lin, L.; Liu, S. Synthesis of γ-Valerolactone by Hydrogenation of Biomass-derived Levulinic Acid over Ru/C Catalyst. Energy Fuels 2009, 23, 3853−3858. (21) Piskun, A. S.; de Haan, J. E.; Wilbers, E.; van de Bovenkamp, H. H.; Tang, Z.; Heeres, H. J. Hydrogenation of Levulinic Acid to gamma-Valerolactone in Water Using Millimeter Sized Supported Ru Catalysts in a Packed Bed Reactor. ACS Sustainable Chem. Eng. 2016, 4, 2939−2950. (22) Akiya, N.; Savage, P. E. Roles of water for chemical reactions in high-temperature water. Chem. Rev. 2002, 102, 2725−2750. (23) Jin, F. M.; Enomoto, H. Rapid and highly selective conversion of biomass into value-added products in hydrothermal conditions: chemistry of acid/base-catalysed and oxidation reactions. Energy Environ. Sci. 2011, 4, 382−397. (24) Tekin, K.; Karagoz, S.; Bektas, S. A review of hydrothermal biomass processing. Renewable Sustainable Energy Rev. 2014, 40, 673− 687. (25) Elliott, D. C.; Biller, P.; Ross, A. B.; Schmidt, A. J.; Jones, S. B. Hydrothermal liquefaction of biomass: Developments from batch to continuous process. Bioresour. Technol. 2015, 178, 147−156. (26) Liu, J.; Zeng, X.; Cheng, M.; Yun, J.; Li, Q.; Jing, Z.; Jin, F. Reduction of formic acid to methanol under hydrothermal conditions in the presence of Cu and Zn. Bioresour. Technol. 2012, 114, 658−662. (27) Jin, F.; Gao, Y.; Jin, Y.; Zhang, Y.; Cao, J.; Wei, Z.; Smith, R. L., Jr High-yield reduction of carbon dioxide into formic acid by zerovalent metal/metal oxide redox cycles. Energy Environ. Sci. 2011, 4, 881−884. (28) Jin, F. M.; Zeng, X.; Liu, J. K.; Jin, Y. J.; Wang, L. Y.; Zhong, H.; Yao, G. D.; Huo, Z. B. Highly efficient and autocatalytic H2O dissociation for CO2 reduction into formic acid with zinc. Sci. Rep. 2015, 4 (4053), 1−8. (29) Steinfeld, A.; Brack, M.; Meier, A.; Weidenkaff, A.; Wuillemin, D. A solar chemical reactor for co-production of zinc and synthesis gas. Energy 1998, 23, 803−814. (30) Osinga, T.; Olalde, G.; Steinfeld, A. Solar carbothermal reduction of ZnO: shrinking packed-bed reactor modeling and experimental validation. Ind. Eng. Chem. Res. 2004, 43, 7981−7988. (31) Steinfeld, A.; Frei, A.; Kuhn, P.; Wuillemin, D. Solar thermal production of zinc and syngas via combined ZnO-reduction and CH4reforming processes. Int. J. Hydrogen Energy 1995, 20, 793−804. (32) Haueter, P.; Moeller, S.; Palumbo, R.; Steinfeld, A. The production of zinc by thermal dissociation of zinc oxidesolar chemical reactor design. Sol. Energy 1999, 67, 161−167. (33) Zeng, X.; Hatakeyama, M.; Ogata, K.; Liu, J.; Wang, Y.; Gao, Q.; Fujii, K.; Fujihira, M.; Jin, F.; Nakamura, S. New insights into highly efficient reduction of CO2 to formic acid by using zinc under mild hydrothermal conditions: a joint experimental and theoretical study. Phys. Chem. Chem. Phys. 2014, 16, 19836−19840.

6523


New Method for Highly Efficient Conversion of Biomass-Derived

Recommend Documents