25212-86-6Relevant articles and documents
Vapor phase hydrodeoxygenation of furfural to 2-methylfuran on molybdenum carbide catalysts
Lee, Wen-Sheng,Wang, Zhenshu,Zheng, Weiqing,Vlachos, Dionisios G.,Bhan, Aditya
, p. 2340 - 2352 (2014)
Vapor phase hydrodeoxygenation (HDO) of furfural over Mo2C catalysts at low temperatures (423 K) and ambient pressure showed high/low selectivity to CO bond/C-C bond cleavage, resulting in selectivity to 2-methylfuran (2MF) and furan of ~50-60% and 2 for deoxygenation, instead of unwanted sequential hydrogenation, was evidenced by the low selectivity to 2-methyltetrahydrofuran. The apparent activation energy and H2 order for 2MF production rates were both found to be invariant with furfural conversion caused by catalyst deactivation, suggesting that (1) the measured reaction kinetics are not influenced by the products of furfural HDO and (2) the loss of active sites, presumably by formation of carbonaceous species observed by TEM analysis, is the reason for the observed catalyst deactivation. The observed half order dependence of 2MF production rates on H2 pressure at different furfural pressures (~0.12-0.96 kPa) and the 0-0.3 order dependence in furfural pressure support the idea of two distinct sites required for vapor phase furfural HDO reactions on Mo2C catalysts. The invariance of 2MF production rates normalized by the number of catalytic centers assessed via ex situ CO chemisorption suggests that metal-like sites on Mo2C catalysts are involved in selective HDO reactions.
Highly dispersed Cu nanoparticles as an efficient catalyst for the synthesis of the biofuel 2-methylfuran
Dong, Fang,Ding, Guoqiang,Zheng, Hongyan,Xiang, Xiaoming,Chen, Linfeng,Zhu, Yulei,Li, Yongwang
, p. 767 - 779 (2016)
Cu/SiO2 catalysts were synthesized by different methods, which greatly influenced their texture and the catalytic performance. The AE-Cu/SiO2 catalyst was prepared via the ammonia evaporation method and showed a 95.5% yield for 2-methylfuran (a promising fuel additive) because of the cooperative effects of surface Cu0, Cu+ species and acid sites, which respectively stemmed from the reduction of highly dispersed CuO species, copper species that fiercely interacted with the support SiO2, and the special structure. The ammonia evaporation method favored the formation of a copper phyllosilicate phase with a lamellar structure, which could provide a large number of Cu nanoparticles and acid sites and further improve the activity and selectivity. Crucially, the stability of the AE-Cu/SiO2 catalyst (>210 h) was also significantly improved due to the enhanced copper-silicon interactions, which could immobilize copper particles and resist the fast transmigration (aggregation and loss) of copper particles in the thermal treatment process. In contrast, the CP-Cu/SiO2 catalyst was synthesized via the conventional precipitation method and presented poor activity and stability toward 2-methylfuran because of large copper particles, severe aggregation and a loss of copper species during reaction. Compared with the conventional CP-Cu/SiO2 catalyst, the use of the AE-Cu/SiO2 catalyst in the synthesis of the biofuel 2-methylfuran could not only improve the yield of the desired product, but also decrease by at least 20 °C the reaction temperature which is propitious for prolonging the lifetime of the Cu/SiO2 catalyst.
Fe/FeOx embedded in LDH catalyzing C-C bond forming reactions of furfural with alcohols in the absence of a homogeneous base
Wang, Lijun,Zhong, Yang,Zhou, Bo
, (2020)
Fe/FeOx embedded in LDH was prepared by reducing the pre-synthesized [Fe(C2O4)3]3? anions intercalated LDH and used as a multi-functional catalyst for synthesis of C7-C9 compound via transfer hydrogenation between furfural (C5) and short-chain alcohols (C2-C4) and a subsequent aldol reaction of furfural with intermediate short-chain aldehydes in the absence of a homogeneous base with furfuryl alcohol as a byproduct. Screening reaction conditions, evaluation and improvement of the cyclic catalytic performance, and determination of catalytically active components were performed, and the results demonstrated that both high conversion and high selectivity to the C[sbnd]C bond forming product can be obtained under a non-oxidizing atmosphere of Ar or H2/Ar mixed gas, a reaction temperature of 140 °C and a reaction time of 4 h; the catalyst was easily deactivated during the cycle experiments, however, its catalytic stability can be effectively improved by depositing Ni with weak reducibility on the surface of Fe nanoparticles at the cost of reducing partial catalytic activity. Fe/FeOx together with LDH as a whole proved to be effective in catalyzing the transfer hydrogenation reaction and the support LDH imparted basic catalytic function to the composite realizing the aldol reaction in the absence of a homogeneous base.
Efficient catalytic transfer hydrogenation of biomass-based furfural to furfuryl alcohol with recycable Hf-phenylphosphonate nanohybrids
Li, Hu,Li, Yan,Fang, Zhen,Smith, Richard L.
, p. 84 - 92 (2019)
An acid-base bifunctional nanohybrid phenylphosphonic acid (PhP) - hafnium (1:1.5) was synthesized through assembly of PhP with HfCl4 for catalytic transfer hydrogenation of furfural (FUR) to furfuryl alcohol (FFA) using 2-propanol as both reaction solvent and hydrogen donor source. An FFA yield of 97.6 % with formation rate of 9760 μmol g?1 h?1 at 99.2 % FUR conversion was obtained with the reaction system at 120 °C for 2 h reaction time. Activation energy (Ea) was estimated to be 60.8 kJ/mol with respect to FUR concentration, which is comparable with or even lower than Ea values attained over metal catalysts. The pronounced catalytic activity of PhP-Hf (1:1.5) is attributed to its moderate acidity and relatively strong basicity. The PhP-Hf (1:1.5) catalyst was demonstrated to maintain its activity for five consecutive reuse cycles.
A gas-phase coupling process for simultaneous production of γ-butyrolactone and furfuryl alcohol without external hydrogen over bifunctional base-metal heterogeneous catalysts
Hu, Qi,Fan, Guoli,Yang, Lan,Cao, Xinzhong,Zhang, Peng,Wang, Baoyi,Li, Feng
, p. 2317 - 2322 (2016)
A solvent-free gas-phase coupling process through hydrogen transfer without external hydrogen supply over novel bifunctional base-metal heterogeneous catalysts was developed for the simultaneous production of γ-butyrolactone and furfuryl alcohol with high yields of 95.0% from biomass-derived compounds. Such a practical, unparallely efficient and environmentally benign process makes it promising in terms of both green sustainable chemistry and industrial perspective.
Cr-free Co-Cu/SBA-15 catalysts for hydrogenation of biomass-derived α-, β-unsaturated aldehyde to alcohol
Srivastava, Sanjay,Mohanty, Pravakar,Parikh, Jigisha K.,Dalai, Ajay K.,Amritphale,Khare, Anup K.
, p. 933 - 942 (2015)
Cr-free bi-metallic SBA-15-supported Co-Cu catalysts were examined in the conversion of biomass-derived α-, β-unsaturated aldehyde (furfural) to value-added chemical furfuryl alcohol (FOL). Co-Cu/SBA-15 catalysts with a fixed Cu loading of 10 wt% and varying Co loadings (2.5, 5, and 10 wt%) were prepared by the impregnation method. The catalysts were characterized by X-ray diffraction, N2 sorption, H2 temperature-programmed reduction, scanning electron microscopy, energy-dispersive X-ray spectroscopy, high-resolution transmission electron microscopy, CO chemisorption, and inductively coupled plasma mass spectrometry. The influence of different reaction parameters such as temperature, pressure, catalyst dosage, and furfural concentration on the catalyst performance was evaluated. Relative to catalysts supported on amorphous silica, the current SBA-15-supported Co-Cu catalysts displayed higher performance, attaining a furfural conversion of 99% and furfuryl alcohol selectivity of 80%. The catalytic reactions were conducted in a 100-mL autoclave at 170 °C and 2 MPa H2 pressure for 4 h.
Highly Selective Reduction of Bio-Based Furfural to Furfuryl Alcohol Catalyzed by Supported KF with Polymethylhydrosiloxane (PMHS)
Yu, Zhaozhuo,Wu, Weibo,Li, Hu,Yang, Song
, (2020)
Hydrogenation of bio-based furfural (FUR) to furfuryl alcohol (FFA) is tremendously expanding the application of biomass in many industries such as resins, biofuels, and pharmaceuticals. However, mass manufacture of FFA from FUR is restrained by strict requirements of reaction conditions and expensive catalysts. In this work, an economical and benign catalytic system, containing an easily prepared and reusable catalyst 5 wt.% KF/ZrO2 and a low-cost hydrogen source polymethylhydrosiloxane (PMHS), was developed to be efficient for the hydrogenation of FUR to high-value FFA under mild conditions. The catalyst reactivity was found to be remarkably influenced by the support acid-base properties and KF loading doge. In the presence of 5 wt.% KF/ZrO2, a high FFA yield of 97% and FUR conversion of 99% could be obtained at 25°C in just 0.5 h, which was superior to those attained with other tested catalysts. The KF/ZrO2 catalyst could be recycled at least five times, with the FFA yield slightly decreasing from 97% to 71%. The spare decrease in FFA yield is possibly attributed to the catalyst pore blocking, as clarified by SEM, BET, XPS, and ICP-MS measurements of the fresh and reused catalysts.
Gas-phase hydrogenation of furfural over Cu/CeO2 catalysts
Jiménez-Gómez, Carmen P.,Cecilia, Juan A.,Márquez-Rodríguez, Imanol,Moreno-Tost, Ramón,Santamaría-González, José,Mérida-Robles, Josefa,Maireles-Torres, Pedro
, p. 327 - 338 (2017)
Cu-CeO2-x catalysts, with a Cu/Ce molar ratio between 0.2 and 6.0, have been synthesized by coprecipitation, calcination and subsequent reduction. These samples have been characterized by X-ray diffraction, H2 temperature-programmed reduction, N2O titration, N2 adsorption-desorption at ?196 °C and X-ray photoelectronic spectroscopy, among other techniques. They exhibit small average particle sizes, high dispersion of copper species, porosity and high metal surface. Their catalytic behavior was evaluated in the gas-phase hydrogenation of furfural (FUR), evidencing high activity and stability due to the strong interaction Cu-CeO2. The highest conversion was attained for catalysts with higher copper content, which display higher metal surface, with a value of 83% after 5 h of time-on-stream (TOS) for the Cu-CeO2-6 catalyst, at 190 °C, by using a H2:FUR molar ratio of 11.5 and a WHSV of 1.5 h?1. In all cases, only furfuryl alcohol (FOL) and 2-methylfuran (MF) were obtained as reaction products, being majority MF for shorter TOS and FOL for longer, which can be explained by the deactivation of the highly hydrogenating sites by carbonaceous deposits and the oxidation of the active phase by water generated in the dehydration process to obtain MF.
Doping Pd/SiO2 with Na+: Changing the reductive etherification of CO to furan ring hydrogenation of furfural in ethanol
Long, Yinshuang,Wang, Yun,Wu, Haihong,Xue, Teng,Wu, Peng,Guan, Yejun
, p. 25345 - 25350 (2019)
The production of biofuels and chemicals by hydrogenation of furfural has attracted much attention recently. Herein the effect of Na+ doping on the catalytic performance of Pd/SiO2 in hydrogenation and reductive-etherification of furfural in ethanol was systematically studied. Two Pd/SiO2 catalysts with and without the modification by Na+ were prepared by impregnation and calcination. Their catalytic properties were compared for the hydrogenation of furfural and furfural diethyl acetal under mild conditions. The silanol groups on Pd/SiO2 catalysed the acetalization of furfural and alcohol and the resulted acetal underwent hydrogenolysis on Pd nanoparticles (NPs) with an average particle size of 8 nm, leading to a moderate yield (～58%) of furfuryl ethyl ether. Doping Na+ on Pd/SiO2 led to the diminishing of silanol groups as well as strong interaction between Na+ and Pd NPs. No acetalization occurred on Na+ modified Pd/SiO2 due to the exchange of H+ of Si-OH with Na+, thus the reductive etherification of CO group in furfural was completely inhibited. Meanwhile the hydrogenation of furan-ring over Na+ coordinated Pd NPs could proceed with very high selectivity (>90%) forming tetrahydrofurfural in high yield. Kinetics study on the hydrogenation of furfural diethyl acetal over Pd/SiO2 and Na+ doped Pd/SiO2 suggested that the Na+ greatly impeded the hydrogenolysis of C-O-C bond of acetal, while the hydrogenation of the furan ring took place selectively.
Bifunctional Lewis and Br?nsted acidic zeolites permit the continuous production of bio-renewable furanic ethers
Padovan,Al-Nayili,Hammond
, p. 2846 - 2854 (2017)
The catalytic valorisation of bio-renewable feedstock often relies upon multi-stage processing of highly-functionalised substrates, resulting in selectivity and processs engineering challenges. Herein, we demonstrate that a bifunctional zeolitic material, containing both Lewis and Br?nsted acid sites in a single catalytic material, permits the continuous production of bio-renewable furanic ethers, such as (butoxy)methyl furan, which possess potential as fuel additives. In contrast to mono-functional catalysts and physical mixtures thereof, the bifunctional Sn- and Al-containing BEA zeolite results in uniquely-high levels of activity, selectivity and stability. Optimal results were obtained over a bifunctional catalyst containing 2 wt% Sn and 0.5 wt% Al, prepared by modified solid state incorporation, which was highly selective (>75%) to the desired ether for over 100 h on stream, and for over 3000 substrate turnovers.
Biocatalytic transformation of furfural into furfuryl alcohol using resting cells of Bacillus cereus
Rodríguez M, Alejandra,Rache, Leidy Y.,Brijaldo, María H.,Romanelli, Gustavo P.,Luque, Rafael,Martinez, José J.
, p. 220 - 225 (2021)
The bioconversion of furfural to furfuryl alcohol is an attractive route in biomass valorization that could replace traditional contaminant methods. The use of whole cells has been explored for this purpose. Bacillus cereus without previous treatment with furanic compounds was used to selectively obtain furfuryl alcohol. Growing and resting cells were employed. Using growing cells of B. cereus, lower yields to alcohol were obtained because of furfural toxicity. However, employing resting cells it was possible to reach higher yields to furfuryl alcohol. Optimal operative conditions were studied: different concentrations of furfural, glucose and molybdenum, pH, and temperature. Thus, glucose (100 mM) and molybdenum (0.1 mM) were added to maintain cell biomass obtaining a yield to furfuryl alcohol close to 80% at 30 °C, pH 7.2 from 30 mM of furfural.
tert-Butanol intervention enables chemoselective conversion of xylose to furfuryl alcohol over heteropolyacids
He, Liang,Li, Hui,Peng, Lincai,Wang, Juan,Wang, Mengmeng,Zhang, Junhua
, p. 5656 - 5665 (2020)
Both the solvent and catalyst play important roles in the chemoselective transformation of biomass-related compounds to fine chemicals and fuels. We report herein an innovative catalytic strategy for the direct valorization of xylose without external H2producing high yield of furfuryl alcohol (FA), which is a versatile platform molecule. The solventtert-butanol served not only as a precursor of the hydrogen honor, but also as a shield to facilitate xylose dehydration and inhibit the polymerization and decomposition reactions of FA. Commercial H4SiW12O40was found to work as a multifunctional catalyst during the cascade conversion and had good reusability. The underlying catalytic mechanism revealed that the Br?nsted and Lewis acid sites co-existed cooperatively to catalyze the xylose dehydration step and the active metal site of W atom adsorbed the hydrogen proton for the transfer hydrogenation of furfural to FA. After the incorporation of the formic acid as a supplemental hydrogen source, an unprecedented FA yield of 90% could be accomplished in a batch reactor under mild conditions. The kinetic behavior describing the conversion of xylose to FA was investigated to monitor the process. The estimated activation energies for xylose dehydration, furfural hydrogenation, and FA decomposition were 85.1, 78.8, and 101.1 kJ mol?1, respectively. This study opens a new avenue for the selective production of FA from hemicellulose-derived pentose in a green and straightforward manner.
Insights into influence of nanoparticle size and metal-support interactions of Cu/ZnO catalysts on activity for furfural hydrogenation
Yang, Xiaohai,Chen, Hongmei,Meng, Qingwei,Zheng, Hongyan,Zhu, Yulei,Li, Yong Wang
, p. 5625 - 5634 (2017)
Cu/ZnO catalysts primarily derived from aurichalcite with Cu/Zn = 0.4-1.1 (mol/mol) were prepared via "decreased pH" coprecipitation method and introduced in hydrogenation of furfural to furfuryl alcohol. The "precursor effect" was clearly confirmed and the catalyst with a Cu/Zn = 0.8 provided the best conversion and TOF. Catalysts were characterized via XRD, FT-IR, N2O titration, TEM, H2-TPR, XPS and AES. The size of Cu nanoparticles and Cu-ZnO interactions were systematically investigated and were found to remarkably influence catalytic activity of the catalysts. Consequently, the best catalytic performance for the catalyst with Cu/Zn = 0.8 was due to the suitable Cu particle size (8 nm) and strong metal-support interactions (SMSI), acting as the Cu-ZnO synergy.
Activity of continuous flow synthesized Pd-based nanocatalysts in the flow hydroconversion of furfural
Garcia-Olmo, Antonio J.,Yepez, Alfonso,Balu, Alina M.,Prinsen, Pepijn,Garcia, Araceli,Maziere, Audrey,Len, Christophe,Luque, Rafael
, p. 5599 - 5604 (2017)
A number of synthesized supported Pd nanomaterials on aluminosilicate supports were investigated in the continuous flow hydroconversion of furfural to a range of furanic derivatives as compared to a commercial Pd/C catalyst. Excellent furfural conversions (>60%) and varying selectivities to products at mild temperatures (90 °C) could be obtained for most catalytic systems, with interesting selectivities to furfuryl alcohol (FOL), 2-methylfuran (MF) and tetrahydrofurfuryl alcohol (THFOL) depending on type of Pd catalyst. A significant deactivation with time on stream was observed for continuous flow synthesized nanomaterials with respect to commercial 5%Pd/C.
Carbon-embedded Ni nanocatalysts derived from MOFs by a sacrificial template method for efficient hydrogenation of furfural to tetrahydrofurfuryl alcohol
Su, Yanping,Chen, Chun,Zhu, Xiaoguang,Zhang, Yong,Gong, Wanbing,Zhang, Haimin,Zhao, Huijun,Wang, Guozhong
, p. 6358 - 6365 (2017)
We report a fast and simple method for the synthesis of Ni-based metal-organic-frameworks (Ni-MOFs). Due to the existence of nickel ions and an organic ligand, the MOFs are employed as a sacrificial template for the facile preparation of carbon-embedded Ni (Ni/C) catalysts by a direct thermal decomposition method. The obtained Ni/C catalysts exhibit excellent catalytic activity for selectively transforming furfural (FAL) to tetrahydrofurfuryl alcohol (THFOL) due to the Ni nanoparticles (NPs) embedded uniformly in the ligand-derived carbon. The exemplified results illustrate that the catalytic performance of the Ni/C catalyst is greatly affected by the calcination conditions (temperature and time), composition of the Ni-MOF precursor and the catalysis conditions. The conversion of FAL and selectivity of THFOL both reached 100% under the conditions of 120 °C, 1 MPa H2 pressure and 120 min of hydrogenation over the Ni/C-500 catalyst, derived from the pyrolysis of Ni-MOFs (Ni:BTC mole ratio of 1.0) at 500 °C for 120 min, which exhibits an average nanoparticle size of ～14 nm and uniform dispersion, and the highest BET surface area (～92 m2 g-1) among all investigated Ni/C catalysts. This facilely prepared heterogeneous catalyst would be very promising for the replacement of noble metal catalysts for the efficient catalytic conversion of biomass-derived feedstocks into value-added chemicals.
Tandem dehydration-transfer hydrogenation reactions of xylose to furfuryl alcohol over zeolite catalysts
Paulino, Priscilla N.,Perez, Rafael F.,Figueiredo, Natália G.,Fraga, Marco A.
, p. 3759 - 3763 (2017)
Dehydration and transfer hydrogenation tandem reactions of xylose to furfuryl alcohol in water/isopropanol were performed on MFI, FAU and BEA zeolites. An unprecedented selectivity of 75% was accomplished on zeolite beta, evidencing the crucial role of th
Pd-Ru/TiO2 catalyst - An active and selective catalyst for furfural hydrogenation
Aldosari, Obaid F.,Iqbal, Sarwat,Miedziak, Peter J.,Brett, Gemma L.,Jones, Daniel R.,Liu, Xi,Edwards, Jennifer K.,Morgan, David J.,Knight, David K.,Hutchings, Graham J.
, p. 234 - 242 (2016)
The selective hydrogenation of furfural at ambient temperature has been investigated using a Pd/TiO2 catalyst. The effect of the solvent was studied and high activity and selectivity to 2-methylfuran and furfuryl alcohol was observed using octane as solvent but a number of byproducts were observed. The addition of Ru to the PdTiO2 catalyst decreased the catalytic activity but improved the selectivity towards 2-methylfuran and furfuryl alcohol with decreased byproduct formation. Variation of the Ru/Pd ratio has shown an interesting effect on the selectivity. The addition of a small amount of Ru (1 wt%) shifted the selectivity towards furfuryl alcohol and 2-methylrofuran. Further increasing the Ru ratio decreased the catalytic activity and also showed a very poor selectivity to 2-methylfuran.
Role of alkali earth metals over Pd/Al2O3 for decarbonylation of 5-hydroxymethylfurfural
Meng, Qingwei,Qiu, Chengwu,Ding, Guoqiang,Cui, Jinglei,Zhu, Yulei,Li, Yongwang
, p. 4377 - 4388 (2016)
A series of Pd/Al2O3 catalysts with different alkali earth metals (Mg, Ca, Sr, Ba) and varying Sr loadings (1.8, 3.5, 5.3, 7 and 8.8 wt%) were investigated for 5-hydroxymethylfurfural (HMF) decarbonylation. The alkali earth metal and content were demonstrated to have profound influences on the metal dispersion, electron density of the metal, acid-base properties of the catalyst, and catalytic performance. The Pd3Sr/Al2O3 catalyst exhibited the highest initial activity and furfuryl alcohol selectivity, achieving a yield of 92%. The key to high decarbonylation selectivity is the suppression of hydrogenolysis and etherification side reactions through the attenuation of the acidity of catalysts. Successful catalytic activity not only lies in the increased metallic surface area, but is also affected by the adsorption properties of the carbonyl group and the poisoning CO produced. The catalytic activity is linearly correlated to the surface metallic area at low modifier loading over PdM/Al2O3 catalysts. But along with further increased metallic surface area over PdXSr/Al2O3, HMF conversion initially increased, reaching a plateau over Pd3Sr/Al2O3 and then decreased with increasing Sr loading. A synergistic effect between the Sr species and metallic Pd was proposed, which promoted the migration of carbonyl adsorption from the support to the surface Pd through the electron donation of Sr species to Al2O3 and metallic Pd.
Solvents as Phase-transfer Catalysts in Reactions initiated by Solid Bases
Bentley, T. William,Jones, Ray V. H.,Larder, Annette H.,Lock, Stephen J.
, p. 2309 - 2310 (1994)
For reactions initiated by solid bases (e.g. potassium hydroxide, sodium hydroxide, potassium carbonate), solvents (e.g. water, ButOH, polyethylene glycol, MeCN, Me2SO) may act as solid-liquid phase transfer catalysts (e.g. for C-H, N-H or O-H alkylation by alkyl halides, or epoxidation by sulfonium or sulfoxonium salts).
Furfuryl alcohol from furfural hydrogenation over copper supported on SBA-15 silica catalysts
Vargas-Hernández,Rubio-Caballero,Santamaría-González,Moreno-Tost,Mérida-Robles,Pérez-Cruz,Jiménez-López,Hernández-Huesca,Maireles-Torres
, p. 106 - 113 (2014)
Vapor phase furfural hydrogenation has been investigated over Cu supported on SBA-15 silica catalysts. These SBA-Cu catalysts, with variable Cu loadings (8, 15 and 20 wt%), have been prepared by impregnation and characterized by N2 sorption, XRD, XPS, N2O decomposition and TEM techniques. Compared with copper chromite, SBA-Cu catalysts showed a better catalytic performance, reaching a furfural conversion of 54 mol% and a selectivity to furfuryl alcohol of 95 mol%, after 5 h of time-on-stream at 170 °C, with the 15 wt% Cu catalyst. The studies of the used catalysts by CNH analysis and thermo-programmed oxidation (TPO) evidenced a lower amount of carbonaceous deposits on this used SBA-15Cu catalyst. Moreover, the study of the copper dispersion by XPS, before and after the catalytic test, revealed that this intermediate copper loading gives rise to the most stable copper particles. The evaluation of the effect of different reaction parameters, such as reaction temperature (170-270 °C), catalyst loadings and furfural concentration and H2 flow, on the catalytic performance has demonstrated that higher conversion are attained at low reaction temperature, and, as expected, by using high catalyst weight and low furfural feed.
The electrocatalytic hydrogenation of furanic compounds in a continuous electrocatalytic membrane reactor
Green, Sara K.,Lee, Jechan,Kim, Hyung Ju,Tompsett, Geoffrey A.,Kim, Won Bae,Huber, George W.
, p. 1869 - 1879 (2013)
The electrocatalytic hydrogenation of biomass derived oxygenates in a continuous electrocatalytic membrane reactor presents a promising method of fuel and chemical production that minimizes usage of solvents and has the potential to be powered using renewable electricity. In this paper we demonstrate the use of a continuous-flow electrocatalytic membrane reactor for the reduction of aqueous solutions of furfural into furfuryl alcohol (FA), tetrahydrofurfuryl alcohol (THFA), 2-methylfuran (MF) and 2-methyltetrahydrofuran (MTHF). Protons needed for hydrogenation were obtained from the electrolysis of water at the anode of the reactor. Pd was identified as the most active monometallic catalyst of 5 different catalysts tested for the hydrogenation of aqueous furfural with hydrogen gas in a high-throughput reactor. Thus Pd/C was tested as a cathode catalyst for the electrocatalytic hydrogenation of furfural. At a power input of 0.1W, Pd/C was 4.4 times more active (per active metal site) as a cathode catalyst in the electrocatalytic hydrogenation of furfural than Pt/C. The main products for the electrocatalytic hydrogenation of furfural were FA (54-100% selectivity) and THFA (0-26% selectivity). MF and MTHF were also detected in selectivities of 8%. Varying the reactor temperature between 30 °C and 70 °C had a minimal effect on reaction rate for furfural conversion. Using hydrogen gas at the anode, in place of water electrolysis, produced slightly higher rates of product formation at a lower power input. Sparging hydrogen gas on the cathode had no effect on reaction rate or selectivity, and was used to examine the addition of recycling loops to the continuous electrocatalytic membrane reactor.
A selective oxidative valorization of biomass-derived furfural and ethanol with the supported gold catalysts
Gao, Yiqi,Tong, Xinli,Zhang, Haigang
, p. 238 - 245 (2020)
The oxidative upgrading of renewable furfural (FUR) and ethanol is an important way to produce high-quality liquid fuel and value-added furanic derivatives. In this work, a series of supported Au catalysts were prepared using the colloid-immobilization technique, and further employed for catalytic oxidative condensation of FUR with ethanol in the presence of molecular oxygen. It is found that, with Au@CaO as the catalyst, 85.9% conversion of FUR and 81.8% selectivity of the product furan-2-acrolein were achieved in the absence of any homogeneous basic additive. The effects of different reactions such as reaction time, temperature and catalyst amount were explored in detail. Also, the influences of calcination temperature and amount of protective agent during the preparation of catalyst were investigated. According to the characterization results of catalyst, it is concluded that the synergistic effect of metallic Au and basic site of CaO support plays a significant role on the selective oxidative condensation. At last, a possible reaction mechanism is proposed based on the catalytic principle and experimental results.
Selective Production of 2-Methylfuran by Gas-Phase Hydrogenation of Furfural on Copper Incorporated by Complexation in Mesoporous Silica Catalysts
Jiménez-Gómez, Carmen Pilar,Cecilia, Juan A.,Moreno-Tost, Ramón,Maireles-Torres, Pedro
, p. 1448 - 1459 (2017)
Copper species have been incorporated in mesoporous silica (MS) through complexation with the amine groups of dodecylamine, which was used as a structure-directing agent in the synthesis. A series of Cu/SiO2 catalysts (xCu-MS) with copper loadings (x) from 2.5 to 20 wt % was synthesized and evaluated in the gas-phase hydrogenation of furfural (FUR). The most suitable catalytic performance in terms of 2-methylfuran yield was obtained with an intermediate copper content (10 wt %). This 10Cu-MS catalyst exhibits a 2-methylfuran yield higher than 95 mol % after 5 h time-on-stream (TOS) at a reaction temperature of 210 °C with a H2/FUR molar ratio of 11.5 and a weight hourly space velocity (WHSV) of 1.5 h?1. After 14 h TOS, this catalyst still showed a yield of 80 mol %. In all cases, carbonaceous deposits on the external surface were the cause of the catalyst deactivation, although sintering of the copper particles was observed for higher copper loadings. This intermediate copper loading (10 wt %) offered a suitable balance between resistance to sintering and tendency to form carbonaceous deposits.
Solvent Tunes the Selectivity of Hydrogenation Reaction over α-MoC Catalyst
Deng, Yuchen,Gao, Rui,Lin, Lili,Liu, Tong,Wen, Xiao-Dong,Wang, Shuai,Ma, Ding
, p. 14481 - 14489 (2018)
Selective activation of chemical bonds in multifunctional oxygenates on solid catalysts is a crucial challenge for sustainable biomass upgrading. Molybdenum carbides and nitrides preferentially activate C=O and C-OH bonds over C=C and C-C bonds in liquid-phase hydrogenation of bioderived furfural, leading to highly selective formations of furfuryl alcohol (FA) and its subsequent hydrogenolysis product (2-methyl furan (2-MF)). We demonstrate that pure-phase α-MoC is more active than β-Mo2C and γ-Mo2N for catalyzing furfural hydrogenation, and the hydrogenation selectivity on these catalysts can be conveniently manipulated by alcohol solvents without significant changes in reaction rates (e.g., > 90% yields of FA in methanol solvent and of 2-MF in 2-butanol solvent at 423 K). Combined experimental and theoretical assessments of these solvent effects unveil that it is the hydrogen donating ability of the solvents that governs the hydrogenation rate of the reactants, while strong dissociative adsorption of the alcohol solvent on Mo-based catalysts results in surface decoration which controls the reaction selectivity via enforcing steric hindrance on the formation of relevant transient states. Such solvent-induced surface modification of Mo-based catalysts provides a compelling strategy for highly selective hydrodeoxygenation processes of biomass feedstocks.
Low-temperature catalytic hydrogenation of bio-based furfural and relevant aldehydes using cesium carbonate and hydrosiloxane
Long, Jingxuan,Zhao, Wenfeng,Xu, Yufei,Wu, Weibo,Fang, Chengjiang,Li, Hu,Yang, Song
, p. 3063 - 3071 (2019)
Selective hydrogenation of unsaturated compounds is mainly carried out by using high-pressure hydrogen in the presence of a precious or transition metal catalyst. Here, we describe a benign approach to efficiently catalyze the hydrogenation of furfural (FUR) to furfuryl alcohol (FFA) over commercially available cesium carbonate using nontoxic and cheap polymethylhydrosiloxane (PMHS) as hydrogen source. Good to excellent FFA yields (≥90%) could be obtained at 25-80 °C by appropriate control of the catalyst dosage, reaction time, and the hydride amount. FUR-to-FFA hydrogenation was clarified to follow a pseudo-first order kinetics with low apparent activation energy of 20.6 kJ mol-1. Mechanistic insights manifested that PMHS was redistributed to H3SiMe, which acted as the active silane for the hydrogenation reactions. Importantly, this catalytic system was able to selectively reduce a wide range of aromatic aldehydes to the corresponding alcohols in good yields of 81-99% at 25-80 °C in 2-6 h.
Manganese-Catalyzed Hydrogenation of Sclareolide to Ambradiol
Zubar, Viktoriia,Lichtenberger, Niels,Schelwies, Mathias,Oeser, Thomas,Hashmi, A. Stephen K.,Schaub, Thomas
, (2021/11/16)
The hydrogenation of (+)-Sclareolide to (?)-ambradiol catalyzed by a manganese pincer complex is reported. The hydrogenation reaction is performed with an air- and moisture-stable manganese catalyst and proceeds under relatively mild reaction conditions at low manganese and base loadings. A range of other esters could be successfully hydrogenated leading to the corresponding alcohols in good to quantitative yields using this easy-to-make catalyst. A scale-up experiment was performed leading to 99.3 % of the isolated yield of (?)-Ambradiol.
Platinum thiolate complexes supported by PBP and POCOP pincer ligands as efficient catalysts for the hydrosilylation of carbonyl compounds
Chang, Jiarui,Chen, Xuenian,Xue, Man-Man,Zhang, Jie
supporting information, p. 2304 - 2312 (2022/02/21)
Diphosphino-boryl-based PBP pincer platinum thiolate complexes, [Pt(SR){B(NCH2PtBu2)2-1,2-C6H4}] (R = H, 1a; Ph, 1b), and benzene-based bisphosphinite POCOP pincer platinum thiolate complexes, [Pt(SR)(tBu2PO)2-1,3-C6H3] (R = H, 2a; Ph, 2b), were prepared
Solvent effect on the rate and direction of furfural transformations during hydrogenation over the Pd/C catalyst
Belskaya, O. B.,Likholobov, V. A.,Mironenko, R. M.
, p. 64 - 69 (2022/02/25)
The rate and directions of transformations during the liquid-phase hydrogenation of furfural with molecular hydrogen in the presence of the 5%Pd/C catalyst (at 423 K, 3 MPa) depend substantially on the chemical nature of the solvent. The main products of
