108-29-2Relevant articles and documents
Selective hydrogenation of levulinic acid to valeric acid and valeric biofuels by a Pt/HMFI catalyst
Kon, Kenichi,Onodera, Wataru,Shimizu, Ken-Ichi
, p. 3227 - 3234 (2014)
We describe one-pot high-yield catalytic pathways for the conversion of levulinic acid (LA) to valeric acid (VA) or valeric acid esters (so-called valeric biofuels) under relatively mild conditions (2 or 8 bar H2, 200 °C). A thorough screening study reveals that a HMFI zeolite-supported Pt metal cluster (Pt/HMFI) with an average cluster size of 1.9 nm shows the highest yield of VA (99%) under solvent-free conditions. The use of ethanol or methanol as solvent changes the selectivity, resulting in 81-84% yields of ethyl valerate (EV) or methyl valerate (MV). Pt/HMFI is also effective for selective formation of valeric acid esters from γVL in alcohols under H2. Kinetics, in situ infrared (IR), and acidity-activity relationship studies show a cooperative mechanism of Pt and Bronsted acid sites of HMFI. VA formation from LA can be driven by Pt-catalyzed hydrogenation of LA to γVL, which undergoes proton-assisted ring-opening by HMFI, followed by Pt-catalyzed hydrogenation. Valeric ester formation from LA is driven by esterification of LA to levulinic ester, which is hydrogenated by Pt. the Partner Organisations 2014.
-
Austin,A.T.,Howard,J.
, p. 3278 - 3284 (1961)
-
Selective and flexible transformation of biomass-derived platform chemicals by a multifunctional catalytic system
Geilen, Frank M. A.,Engendahl, Barhel,Harwardt, Andreas,Marquardt, Wolfgang,Klankermayer, Juergen,Leitner, Walter
, p. 5510 - 5514 (2010)
(Figure Presented) A sustainable supply chain: The controlled transformation of the biomassderived platform compounds levulinic acid (LA) and itaconic acid (IA) into the corresponding lactones, diols, or cyclic ethers (see picture) by using a multifunctional molecular catalyst is described.
Hydrogenation of biomass-derived compounds containing a carbonyl group over a copper-based nanocatalyst: Insight into the origin and influence of surface oxygen vacancies
Hu, Qi,Yang, Lan,Fan, Guoli,Li, Feng
, p. 184 - 195 (2016)
New Mn-containing spinel-supported copper nanocatalysts were directly generated via a Cu-Mn-Al layered double hydroxide precursor route and employed in gas-phase hydrogenation of dimethyl succinate (DMS) to γ-butyrolactone (GBL). It was found that the introduction of manganese into catalyst precursors led to the formation of Mn-containing spinel phases, thereby giving rise to highly dispersive Cu0 nanoparticles and a large number of surface defects (i.e., oxygen vacancies (Ov), Mn2+ species) in reduced catalysts. As-formed copper-based nanocatalysts exhibited exceptional catalytic hydrogenation performance with stability enduring up to 100 h. Such high catalytic efficiency could reasonably be attributed to the surface synergism between Mn2+-Ov-Mn2+ defect structures and active metallic copper species, which controlled the key to hydrogenation related to the adsorption of DMS molecules and following activation of carbonyl groups and the dissociation of hydrogen. Most importantly, such copper-based nanocatalysts displayed great potential applications in the hydrogenations of other biomass-derived compounds containing carbonyl groups (e.g., acetol, levulinic acid, levulinic acid esters, and furfural). The present strategy enables us to tune the surface structures of catalysts for designing new type of copper-based catalysts with significantly enhanced catalytic performance.
A novel hafnium-graphite oxide catalyst for the Meerwein-Ponndorf-Verley reaction and the activation effect of the solvent
Li, Xiaomin,Du, Zhengjiang,Wu, Yi,Zhen, Yadong,Shao, Rixin,Li, Bingqi,Chen, Chengmeng,Liu, Quansheng,Zhou, Huacong
, p. 9985 - 9995 (2020)
Construction and application of novel hydrogenation catalysts is important for the conversion of carbonyl or aldehyde compounds into alcohols in the field of biomass utilization. In this work, a novel, efficient, and easily prepared hafnium-graphite oxide (Hf-GO) catalyst was constructed via the coordination between Hf4+ and the carboxylic groups in GO. The catalyst was applied into the hydrogenation of biomass derived carbonyl compounds via the Meerwein-Ponndorf-Verley (MPV) reaction. The catalyst gave high efficiency under mild conditions. An interesting phenomenon was found whereby the activity of the catalyst increased gradually in the initial stage during reaction. The solvent, isopropanol, was proved to have an activation effect on the catalyst, and the activation effect varied with different alcohols and temperatures. Further characterizations showed that isopropanol played the activation effect via replacing the residual solvent (DMF) in micro- and mesopores during the preparation process, which was hard to be completely removed by common drying process.
Stabilization of cobalt catalysts by embedment for efficient production of valeric biofuel
Sun, Peng,Gao, Guang,Zhao, Zelun,Xia, Chungu,Li, Fuwei
, p. 4136 - 4142 (2014)
We herein report, for the first time, a bifunctional base-metal catalyst (Co@HZSM-5) that acts as an efficient alternative to noble-metal catalysts (e.g., Pt, Ru) for the conversion of levulinic acid into valeric biofuel under batch and fixed-bed reactor conditions. The cobalt nanoparticles were embedded in HZSM-5 crystals and catalyzed the sequential hydrogenations of the ketone and alkene functional groups; meanwhile, the acidic zeolite catalyzed the ring opening of the γ-valerolactone intermediate. Although base metals (e.g., Co) are abundant and inexpensive, their sintering and/or leaching under liquid-phase conditions always lead to the irreversible deactivation of the catalyst. In this system, the embedment structure stabilizes the nanoparticles, and Co@HZSM-5 could be used up to eight times. This work provides a practical clue toward the stabilization of base-metal catalysts and will inspire the development of large-scale biorefinery.
-
Mosher,Preiss
, p. 5605 (1953)
-
Synergy between the metal nanoparticles and the support for the hydrogenation of functionalized carboxylic acids to diols on Ru/TiO2
Primo, Ana,Concepcion, Patricia,Corma, Avelino
, p. 3613 - 3615 (2011)
Ruthenium nanoparticles supported on titania are over three times more active than conventional ruthenium on carbon for the hydrogenation of lactic acid. This superior catalytic activity can be due to a combined action of small ruthenium nanoparticles and the titania support.
RANEY Ni catalyzed transfer hydrogenation of levulinate esters to γ-valerolactone at room temperature
Yang, Zhen,Huang, Yao-Bing,Guo, Qing-Xiang,Fu, Yao
, p. 5328 - 5330 (2013)
A catalytic transfer hydrogenation process was developed for the production of γ-valerolactone (GVL) from ethyl levulinate (EL) and a H-donor at room temperature. Ethyl levulinate was almost quantitatively converted to γ-valerolactone. Further, a two step process for producing GVL from biomass derived platform molecules was also reported. The Royal Society of Chemistry 2013.
Single pot conversion of furfuryl alcohol to levulinic esters and γ-valerolactone in the presence of sulfonic acid functionalized ILs and metal catalysts
Hengne, Amol M.,Kamble, Sumit B.,Rode, Chandrashekhar V.
, p. 2540 - 2547 (2013)
Ionic liquids functionalized with acidic anions, HSO4, ClSO 3H, PTSA, TFA (MIm), HSO4 and TFA (NMP) were found to efficiently (99% conversion) catalyze the alcoholysis of furfuryl alcohol (FAL) in the presence of methanol, ethanol, n-butanol and isopropyl alcohol (IPA) to the corresponding levulinic acid esters under mild temperature (90-130 °C) conditions. The extended alkyl chain length of [MIm] using 1,4-butane sultone enhanced the Bronsted acidity of [BMIm-SH][HSO4] catalyst resulting into the highest selectivity of >95% to Me-LA. An increase in both temperature and catalyst concentration increased the furfuryl alcohol conversion and selectivity to levulinate esters. In contrast, an increase in the substrate concentration from 5 to 15% caused a decrease in Me-LA selectivity due to accumulation of intermediate ethers of furfuryl alcohol. Using a combination of [BMIm-SH][HSO4] and 5% Ru/C catalyst, direct conversion of FAL to γ-valerolactone (GVL) is shown for the first time. A complete conversion of FAL with the highest selectivity of 68% to GVL could be achieved under optimum conditions while higher Ru loading enhanced the GVL selectivity to 94% in the hydrogenation step of this tandem approach. Our catalyst system could be efficiently recycled five times retaining the original activity and selectivity levels.
Direct catalytic transformation of biomass derivatives into biofuel component γ-valerolactone with magnetic nickel-zirconium nanoparticles
Li, Hu,Fang, Zhen,Yang, Song
, p. 135 - 142 (2016)
A series of mixed oxide nanoparticles were prepared by a coprecipitation method and characterized by many techniques. Nickel-zirconium oxide catalysts and their partially reduced magnetic counterparts were highly efficient in the direct transformation of biomass derivatives, including ethyl levulinate, fructose, glucose, cellobiose, and carboxymethyl cellulose, into γ-valerolactone (GVL) without the use of an external hydrogen source, producing a maximum GVL yield of 95.2 % at 200 °C for 3 h with hydrogen-reduced magnetic Zr5Ni5 nanoparticles (-1 h-1). Moreover, the magnetic Zr5Ni5 nanoparticles were conveniently recovered by means of a magnet for five cycles with almost constant activity. Attractive separation: Acid-base bifunctional NiZr nanocatalysts with strong magnetism show high activity and reusability in the transformation of biomass derivatives, including EL, fructose, glucose, cellobiose, and carboxymethyl cellulose, into γ-valerolactone (GVL) with 95.2 % yield and 98 % selectivity (see figure).
High-yield production of levulinic acid from cellulose and its upgrading to γ-valerolactone
Ding, Daqian,Wang, Jianjian,Xi, Jinxu,Liu, Xiaohui,Lu, Guanzhong,Wang, Yanqin
, p. 3846 - 3853 (2014)
Direct catalytic conversion of cellulose to levulinic acid (LA) by niobium-based solid acids and further upgrading to γ-valerolactone (GVL) on a Ru/C catalyst were realized through sequential reactions in a reactor. Firstly, using aluminium-modified mesoporous niobium phosphate as a catalyst, cellulose can be directly converted to LA with as high as 52.9% yield in aqueous solution, even in the presence of the Ru/C catalyst. To the best of our knowledge, this is the best result over a heterogeneous catalyst so far. It was found that the type of acid (Lewis and Bronsted acids) and acid strength had an influence on the yield of LA; the doping of aluminium can enhance the strong Lewis and Bronsted acids, especially the strong Lewis acid, thus resulting in the increase of LA yield from cellulose as well as from glucose and HMF. Such an enhancement by a Lewis acid on LA yield from HMF was further confirmed by adding lanthanum trifluoroacetate [(TfO)3La], a strong Lewis acid, in the catalytic system (HCl, (TfO)3H, niobium phosphate), indicating that a suitable ratio of Lewis/Bronsted acid is important for higher selectivity to LA from HMF, as well as from cellulose. Then, after replacing N2 with H2, the generated LA in the reaction mixture can be directly converted to γ-valerolactone through hydrogenation over the Ru/C catalyst without further separation of LA. This journal is the Partner Organisations 2014.
Simple and efficient conversion of cellulose to γ-valerolactone through an integrated alcoholysis/transfer hydrogenation system using Ru and aluminium sulfate catalysts
Huang, Yao-Bing,Yang, Tao,Luo, Yu-Jia,Liu, An-Feng,Zhou, Yi-Han,Pan, Hui,Wang, Fei
, p. 6252 - 6262 (2018)
The direct conversion of cellulose to specific chemicals represents an important but challenging area that attracts much attention. In this study, we report, for the first time, a one-step conversion of cellulose to γ-valerolactone (GVL), a platform molecule with multiple applications, by integrating alcoholysis and transfer hydrogenation systems over mixed metal salt and Ru catalysts without external hydrogenation. A maximum GVL yield of 51.2% was obtained at 180 °C for 70 min reaction time with microwave heating. The metal salt effectively catalyzed cellulose alcoholysis to generate levulinate in isopropanol, which was also the hydrogen donor for the subsequent catalytic transfer hydrogenation of levulinate to GVL over the Ru/ZrO2 catalyst. It was found that the types of metal center and support material had a significant influence on the reactivity of the catalyst for the catalytic transfer hydrogenation (CTH) reaction, i.e., concerning the existence of sulfuric acid species and water in the reaction system. Microwave heating was demonstrated to be an effective method for cellulose-to-GVL conversion as compared to conventional oil heating, through drastically reducing the reaction time and avoiding decomposition of the reagents. The catalysts were successfully recycled and reused with high reactivity. Finally, the system was also applied to the synthesis of GVL from real biomass, demonstrating the high applicability and potential of the catalytic system for industrial production.
-
Nikishin et al.
, (1976)
-
Porous Organic Zirconium Phosphonate as Efficient Catalysts for the Catalytic Transfer Hydrogenation of Ethyl Levulinate to γ-Valerolactone without External Hydrogen
Wang, Jianjia,Wang, Ruiying,Zi, Huimin,Wang, Haijun,Xia, Yongmei,Liu, Xiang
, p. 750 - 759 (2018)
Organic hybrid zirconium phosphonate materials (ZrATMP, ZrEDTMPS, ZrDTPMPA, and ZrHEDP) were synthesized through reaction of organic phosphonic acid sodium salt and ZrOCl2 in water, which exhibited high catalytic activity on the conversion of ethyl levulinate (EL) to γ-valerolactone (GVL) in the presence of isopropanol. The obtained catalysts were characterized by FT-IR, TGA, XRD, BET, XPS, ICP-AES, SEM, TEM, NH3-TPD, and CO2-TPD. The results demonstrate that the number of acid sites and basic sites between the layers of the catalysts play a very important role in promoting the conversion of EL to GVL and that the functional groups that exist in phosphates could regulate the number of acid and basic sites. Meanwhile, the catalysts could be easily separated from the reaction system and reused at least five times without any obvious decrease in activity or selectivity.
γ-valerolactone ring-opening and decarboxylation over SiO 2/Al2O3 in the presence of water
Bond, Jesse Q.,Martin Alonso, David,West, Ryan M.,Dumesic, James A.
, p. 16291 - 16298 (2010)
γ-Valerolactone (GVL) has been identified as a promising, sustainable platform molecule that can be produced from lignocellulosic biomass. The chemical flexibility of GVL has allowed the development of a variety of processes to prepare renewable fuels and chemicals. In the present work involving a combination of computational and experimental studies, we explore the factors governing the ring-opening of GVL to produce pentenoic acid isomers, as well as their subsequent decarboxylation over acid catalysts or hydrogenation over metal catalysts. The ring-opening of GVL has shown to be a reversible reaction, while both the decarboxylation and hydrogenation reactions are irreversible and kinetically controlled under the conditions studied (temperatures from about 500 to 650 K). The most significant contributor to lactone reactivity toward ring-opening is the size of the ring, with γ- lactones being more stable and less readily opened than δ- and ε-analogues. We have observed that the presence of either a C=C double bond or a lactone (which opens to form a C=C double bond) is necessary for appreciable rates of decarboxylation to occur. Olefinic acids exhibit higher rates of decarboxylation than the corresponding lactones, suggesting that the decarboxylation of alkene acids provides a lower energy pathway to olefin production than the direct decarboxylation of lactones. We observe lower rates of decarboxylation as the chain length of alkene acids increases; however, acrylic acid (3-carbon atoms) does not undergo decarboxylation at the conditions tested. These observations suggest that particular double bond configurations yield the highest rates of decarboxylation. Specifically, we suggest that the formation of a secondary carbenium ion in the β position leads to high reactivity for decarboxylation. Such an intermediate can be formed from 2- or 3-alkene acids which have at least four carbon atoms.
Ruthenium p-cymene complexes with α-diimine ligands as catalytic precursors for the transfer hydrogenation of ethyl levulinate to γ-valerolactone
Biancalana, Lorenzo,Fulignati, Sara,Antonetti, Claudia,Zacchini, Stefano,Provinciali, Giacomo,Pampaloni, Guido,Raspolli Galletti, Anna Maria,Marchetti, Fabio
, p. 17574 - 17586 (2018)
The ruthenium compounds [(η6-p-cymene)RuCl{κ2N-(HCNR)2}]NO3 (R = 4-C6H4Me, [1]NO3; 4-C6H4OH, [2]NO3; C6H11═Cy, [3]NO3; 4-C6H10OH, [4]NO3; tBu, [5]NO3) were prepared in high yields from [(p-cymene)RuCl2]2, AgNO3 and the appropriate α-diimine. Compounds [2]PF6 and [4]PF6 were obtained by a straightforward reaction of [(η6-p-cymene)RuCl(MeCN)0.66]PF6, [6]PF6, with α-diimine, whereas [4]BPh4 was obtained by metathesis between [4]NO3 and NaBPh4. All the ruthenium products were characterized by analytical methods, IR, NMR and UV-Vis spectroscopy; in addition, the structure of [1]NO3 was ascertained by an X-ray diffraction study. Compounds [1-4]NO3, [4]PF6 and [4]BPh4 were investigated as catalytic precursors in the transfer hydrogenation reaction of ethyl levulinate to γ-valerolactone in isopropanol solution under microwave irradiation. [4]BPh4 was revealed to be the best catalytic precursor, affording γ-valerolactone in 62% yield under optimized experimental conditions.
Garrett,Lewis
, p. 1095 (1923)
Vapor-phase hydrogenation of levulinic acid to Γ-valerolactone over Cu-Ni bimetallic catalysts
Yoshida, Rei,Sun, Daolai,Yamada, Yasuhiro,Sato, Satoshi,Hutchings, Graham J.
, p. 79 - 82 (2017)
Vapor-phase hydrogenation of levulinic acid (LA) to γ-valerolactone (GVL) was performed over SiO2-supported Cu-Ni bimetallic catalysts with different Cu/Ni weight ratios under ambient H2 pressure. Characterization of the catalysts was carried out using powder X-ray diffraction, temperature-programmed reduction and thermogravimetric analysis. In contrast to the monometallic catalysts i.e. Ni/SiO2 and Cu/SiO2, the Cu-Ni/SiO2 bimetallic catalyst with a Cu/Ni weight ratio of 6/14 exhibits an excellent catalytic activity, and gave a GVL yield higher than 99% with a productivity of 1.64kgGVLkgcat.?1h?1 at 250°C and at a high WHSV of 1.65h?1 for 50h.
Boosting levulinic acid hydrogenation to value-added 1,4-pentanediol using microwave-assisted gold catalysis
Bucciol,Tabasso,Grillo,Menegazzo,Signoretto,Manzoli,Cravotto
, p. 267 - 277 (2019)
Microwave (MW) -assisted levulinic acid (LA) hydrogenation has been performed over two gold catalysts (commercial 1 wt% Au/TiO2 by AUROlite and 2.5 wt% Au/ZrO2, prepared using deposition-precipitation). MW-assisted LA hydrogenation was carried out in water and in solvent-free conditions via (i) H-transfer and (ii) molecular H2. Au/TiO2 promoted complete LA conversion and the further reduction of the produced GVL to 1,4-pentanediol (1,4-PDO) in the presence of 50 bar H2 at 150 °C (4-hour reaction). Interestingly, selectivity to 1,4-PDO was complete at 200 °C. Extended characterisation highlighted the cooperative role played by the gold nanoparticles and the support, onto which activated hydrogen atoms spillover to react with LA. This results in the remarkable activity of Au/TiO2. Both catalysts showed structural and morphological stability under reaction conditions. It was possible to reactivate the Au/TiO2 catalyst by MW-assisted oxidation, paving the way for catalyst recycling directly inside the MW reactor.
Selective Levulinic Acid Hydrogenation in the Presence of Hybrid Dendrimer-Based Catalysts. Part I: Monometallic
Maximov, Anton L.,Zolotukhina, Anna V.,Mamedli, Adila A.,Kulikov, Leonid A.,Karakhanov, Edward A.
, p. 222 - 233 (2018)
Hybrid Ru-containing catalysts, based on poly(propylene imine) (PPI) dendrimers, immobilized in silica pores, were synthesized and characterized by transmission electron microscopy and X-ray photoelectron spectroscopy. The synthesized Ru catalysts proved their efficiency in the selective hydrogenation of levulinic acid and its esters at 80 °C, 30 bar of H2, and 50 % volume substrate concentration in water. Quantitative yields of γ-valerolactone were obtained for both micro- and mesoporous Ru catalysts within 2 h with catalytic activity as high as 1610 h?1. The reaction rate and selectivity on γ-valerolactone were found to depend on several factors such as carrier structure, temperature, presence of water, and substrate/Ru ratio. The novelty of these hybrid materials is the presence of both weak acid (SiO2) and organic base centers (dendrimer amino groups), enhancing the dispersion of Ru nanoparticles. The presence of amino groups in the catalyst stabilizes the Ru nanoparticles during the synthesis and promotes the adsorption of levulinic acid on the surface of Ru nanoparticles during the reaction. Synthesized hybrid Ru catalysts can be reused several times without significant loss of activity.
Conversion of levulinic acid into γ-valerolactone using Fe3(CO)12: mimicking a biorefinery setting by exploiting crude liquors from biomass acid hydrolysis
Metzker, Gustavo,Burtoloso, Antonio C. B.
, p. 14199 - 14202 (2015)
The conversion of biomass-derived levulinic acid (LA) into gamma-valerolactone (GVL) using formic acid (FA) and Fe3(CO)12 as the catalyst precursor was achieved in 92% yield. To mimic a biorefinery setting, crude liquor (containing 20% LA) from the acid hydrolysis of sugarcane biomass in a pilot plant facility was directly converted into GVL in good yield (50%), without the need for isolating LA.
Catalytic transfer hydrogenation of ethyl levulinate to γ-valerolactone over zirconium-based metal-organic frameworks
Valekar, Anil H.,Cho, Kyung-Ho,Chitale, Sachin K.,Hong, Do-Young,Cha, Ga-Young,Lee, U-Hwang,Hwang, Dong Won,Serre, Christian,Chang, Jong-San,Hwang, Young Kyu
, p. 4542 - 4552 (2016)
A series of highly crystalline, porous, zirconium-based metal-organic frameworks (Zr-MOFs) with different ligand functionalities and porosities were applied for catalytic transfer hydrogenation of ethyl levulinate (EL) to form γ-valerolactone (GVL), using isopropanol as a hydrogen donor. The roles of the ligand functionality and the metal center of the Zr-MOFs were identified and reaction parameters optimized, for selective production of GVL. The maximum yield of GVL (up to 92.7%) was achieved in 2 h at 200 °C with UiO-66(Zr). Interestingly, zirconium trimesate (MOF-808) emerged as the most suitable candidate, with the highest GVL formation rate (94.4 μmol g-1 min-1) among the catalysts tested at 130 °C. It was also found to be effective in conversion of EL to GVL in an open system using the solvent refluxing method. Both the catalysts (UiO-66(Zr) and MOF-808) were recycled at least five times under their specified reaction conditions without a notable change in catalytic activity and product selectivity. Fresh and recycled catalysts were characterized in detail using X-ray powder diffraction (XRD), N2 adsorption-desorption, thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) in order to understand the stability and structural changes that occurred in the catalysts. Finally, a plausible reaction mechanism was presented on the basis of active sites present in catalysts confirmed by characterization results.
Production of gamma-valerolactone from sugarcane bagasse over TiO2-supported platinum and acid-activated bentonite as a co-catalyst
Putro, Jindrayani N.,Kurniawan, Alfin,Soetaredjo, Felycia E.,Lin, Shi-Yow,Ju, Yi-Hsu,Ismadji, Suryadi
, p. 41285 - 41299 (2015)
Nowadays, biomass utilization has become the center of attention for researchers worldwide and is driven by the depletion of global petroleum supplies for the production of energy and valuable chemicals while easing the atmospheric CO2 burden. We propose here a green strategy for transforming sugarcane bagasse into gamma-valerolactone (GVL), an attractive platform molecule that can be further converted into a variety of chemical derivatives for wide use in industrial applications. Our recent strategy involves the solid acid-catalyzed hydrothermal conversion of cellulose and hemicellulose derived from biomass to give an aqueous solution comprising levulinic acid (LA), followed by catalytic hydrogenation of LA to GVL. Native and acid-activated bentonites were used as solid acid catalysts to promote hydrothermal conversion of cellulose and hemicellulose. The maximum achievable yield of LA was 159.17 mg per gram of oven-dried biomass for 60 min reaction at 473.2 K in the presence of a 2% acid-activated bentonite catalyst. Catalytic hydrogenation reactions of LA to GVL over 1% Pt@TiO2 and acid-activated bentonite as a co-catalyst were performed at temperatures of 393.2-473.2 K and residence times of 120-360 min. The combined solid catalyst gave an attractive performance with respect to LA conversion (～100%) and GVL selectivity (95%) under milder reaction conditions in comparison to 1% Pt@TiO2 without an acid co-catalyst. The spent catalyst could be reused for five consecutive hydrogenation cycles with a marginal decrease in the catalytic activity and GVL selectivity. Coke formation was believed to be the main cause of catalyst poisoning and calcination of the spent catalyst under a stream of pure oxygen at 723.2 K was applied for removing coke deposits from the active catalyst sites, thus restoring the catalytic performance.
Selective hydrogenation of biomass derived substrates using ionic liquid-stabilized ruthenium nanoparticles
Julis, Jennifer,Hoelscher, Markus,Leitner, Walter
, p. 1634 - 1639 (2010)
Ionic liquid-stabilized ruthenium nanoparticles with an average size between 2-3 nm are very active catalysts for the hydrogenation of biomass derived substrates. Their catalytic performance complements that of classic homogeneous and heterogeneous ruthenium catalysts.
Ru-decorated N-doped carbon nanoflakes for selective hydrogenation of levulinic acid to γ-valerolactone and quinoline to tetrahydroquinoline with HCOOH in water
Chauhan, Arzoo,Kar, Ashish Kumar,Srivastava, Rajendra
, (2022/03/27)
The effective dissociation of biomass-derived formic acid, as a sustainable hydrogen source, in water is explored for the hydrogenation of levulinic acid (LA) and quinoline. Ru decorated carbon nanoflakes prepared by carboreduction (in Ar/H2 atmosphere) of Ru containing N-doped carbon were used as catalysts. The successful formation of Ru-decorated N-doped carbons was confirmed by numerous spectroscopic tools. The catalyst exhibited outstanding activity and selectivity for the hydrogenation of LA and quinoline using formic acid as a hydrogen donor in water under mild conditions. The catalyst afforded 99.8% LA conversion and 100% selectivity for γ-valerolactone (GVL), whereas 99.8% quinoline conversion and 93% selectivity for 1,2,3,4-tetrahydroquinoline (THQ) were obtained. Recycling experiments suggested that the catalyst was stable even after the 5 cycles. Various controlled experiments and characterizations were conducted to demonstrate the structure-activity relations and suggest plausible reaction mechanisms for the hydrogenation of LA and quinoline. The exploration of formic acid as a sustainable H2 source and the development of metal decorated N-doped carbons for hydrogenation of LA and quinoline will be fascinating to catalysis researchers and industrialists.
Photo-Thermo-Dual Catalysis of Levulinic Acid and Levulinate Ester to γ-Valerolactone
Bunrit, Anon,Butburee, Teera,Liu, Meijiang,Huang, Zhipeng,Meeporn, Keerati,Phawa, Chaiyasit,Zhang, Jian,Kuboon, Sanchai,Liu, Huifang,Faungnawakij, Kajornsak,Wang, Feng
, p. 1677 - 1685 (2022/01/28)
Herein, we developed photo-Thermo-dual catalytic strategies for the production of γ-valerolactone (GVL) from levulinic acid (LA) and its ester using platinum-loaded TiO2 as a dual-functional catalyst. Both catalytic systems were evaluated under mild reaction conditions. In the photocatalysis system, a base plays crucial roles in the conversion of LA and EL to GVL. The control experiments reveal that plausible mechanistic pathways of both systems proceed via the hydrogenation of the ketone group of LA to the corresponding alcohol as a major intermediate followed by a subsequent cyclization step to GVL. This dual-functional catalyst provides alternative strategies for the conversion of LA and its ester into GVL, which could pave the way for biomass utilization in a more effective and practical manner.
Renewable bio-based routes to γ-valerolactone in the presence of hafnium nanocrystalline or hierarchical microcrystalline zeotype catalysts
Antunes, Margarida M.,Fernandes, Auguste,Pillinger, Martyn,Ribeiro, Filipa,Silva, Andreia F.,Valente, Anabela A.
, p. 56 - 71 (2022/01/19)
Different renewable bio-based routes leading to the versatile bioproduct γ-valerolactone (GVL) were studied in integrated fashions, starting from furfural (Fur), α-angelica lactone (AnL) and levulinic acid (LA), in the presence of multifunctional hafnium-
