2-methylfuran Research Articles

A high-performance porous carbon coated CoxP dual functional catalyst for upgrading of furfuryl alcohol

Cobalt phosphides exhibit dual catalytic characteristics as both metal and acid, rendering them widely employed in the organic chemicals refining. Yet, their utilization in the hydrodeoxygenation of furanic molecules derived from biomass remains underexplored. In this study, we fabricated a porous carbon coated cobalt phosphide catalysts (CoxP@C) by pyrolysis and gas-phosphidation of Co-MOFs, and systemically elucidated the synergistic effect of Co-P on hydrodeoxygenation of furfuryl alcohol to produce 2-methyl furan. Phosphidation generated a substantial quantity of positively-charged Coδ+ species through Co-P bonding, and the intensified charge-transfer from cobalt to phosphorous caused the Coδ+ species more electro-deficiency, and enhanced both hydrogen dissociation centers and acid sites when the P/Co molar ratio reached 1.2, thereby synergically boosting hydrodeoxygenation performance. The optimized CoxP@C achieved a 90 % yield of 2-methyl furan under mild conditions (140 °C and 2.5 MPa), while also demonstrating robust recyclability. This study underscores the potential benefits of cobalt phosphide catalyst for the hydrogenative upgrading of biomass-derived molecules.

Genotoxic mode of action and threshold exploration of 2-methyl furan under 120-day sub-chronic exposure in male Sprague-Dawley rats

2-Methylfuran (2-MF) is an important member of the furan family generated during food thermal processing. An in-vivo multiple endpoint genotoxicity assessment system was applied to explore the genotoxic mode of action and threshold of 2-MF. Male Sprague–Dawley rats received 2-MF by oral gavage at doses of 0.16, 0.625, 2.5, and 10 mg/kg.bw/day for 120 days. An additional 15 days were granted for recovery. The Pig-a gene mutation frequency of RET and RBC showed significant increases among the 2-MF groups on day 120. After a 15-day recovery period, the Pig-a gene mutation frequency returned to levels similar to those in the vehicle control. The tail intensity (TI) values of peripheral blood cells at a dose of 10 mg/kg.bw/day significantly increased from day 4 and remained at a high level after the recovery period. No statistical difference was found in the micronucleus frequency of peripheral blood between any 2-MF dose group and the corn oil group at any timepoint. 2-MF may not induce the production of micronuclei, but it could cause DNA breakage. It could not be ruled out that 2-MF may accumulate in vivo and cause gene mutations. Hence, DNA, other than the spindle, may be directly targeted. The mode of action of 2-MF may be that it was metabolized by EPHX1 to more DNA-active metabolites, thus leading to oxidative and direct DNA damage. The point of departure (PoD) of 2-MF-induced genotoxicity was derived as 0.506 mg/kg bw/day.

Carbon-coated nickel phosphide with enriched surface Niδ+ sites enables an exceptionally high productivity of 2-methylfuran from biomass upgrading

A carbon-coated nickel phosphide composite catalyst, Ni2P@C, was fabricated by a PVP-assisted pyrolysis–phosphidation of Ni-MOF, affording an exceptionally high-efficiency production of 2-methylfuran via HDO of furfuryl alcohol at mild temperature.

Au nanoparticles confined in self-assembled Zn(ii) metal–organic cubane cages for light-driven conversion of furfural to 2-methyl furan in biofuel production

A polyoxometalate Zn(ii) cubane cage with intrinsic confined spaces constructed by the self-assembly of tetrametallic cubane clusters was obtained and utilized as a skeletal support for the encapsulation of gold nanoparticles.

A hybrid GA-ANN and correlation approach to developing a laminar burning velocity prediction model for isooctane/blends-air mixtures

Surrogate fuels offer a cost-effective way to predict the combustion properties of transportation fuels like diesel, gasoline, kerosene, etc. Iso-octane (2,2,4-trimethylpentane) is a key gasoline reference and surrogate component. Researchers explore alternative fuels and their combustion characteristics to enhance efficiency and reduce emissions. The rising interest lies in the blending of isooctane with various alternative fuels, aiming for cleaner and more efficient combustion. In this current study, a machine learning method called Feed-Forward Artificial Neural Network (FFANN) with back-propagation (BP) was employed to forecast the laminar burning velocity (LBV) of isooctane/blends – air mixtures. A total of eleven blends including ammonia, hydrogen, methane, methanol, ethanol, butanol, n-heptane, 2-methyl furan (2-MF), 2,5-dimethylfuran (2,5-DMF), 2-methyl tetrahydrofuran (2-MTHF), and syngas were examined. The artificial neural network (ANN) model was created using a dataset consisting of 2234 data points gathered from the past experimental literature since 1983. To enhance the ANN's predictive capability, a combination of the random search CV technique and selective testing approach was utilized for optimizing ANN hyperparameters, while the genetic algorithm (GA) was deployed to optimize the ANN's weight values. The development of the ANN model was carried out within the Python software environment, utilizing the Keras application programming interface. The constructed GA-ANN model was compared to a variety of other machine learning (ML) models developed within this study, including generalized linear regression (GLR), support vector machine (SVM), random forest (RF), artificial neural network (ANN), and XGBoost regression. When evaluated on the testing set, which constitutes 15% of the complete dataset, the GA-ANN model demonstrated superior performance compared to all other ML models utilized in this research, achieving an impressive prediction accuracy with the coefficient of determination (R2) of 0.9910, root mean square error (RMSE) of 0.8231, and a mean absolute error (MAE) of 0.643. Additionally, a common LBV correlation for all isooctane/blend-air mixtures was created using the extended Gulder’s LBV formulation with the input parameters including pressure, temperature, equivalence ratio, and molar fraction of blend. This correlation results showed very minimum deviation from the experimental with an RMSE value of less than 0.38541.

Products and yields for the NO3 radical initiated atmospheric degradation of 2-methylfuran (2-MF, CH3–C4H3O)

Furans represent a group of oxygenated, heterocyclic, organic compounds that are emitted during biomass burning (BB). Notably, these compounds undergo rapid oxidation, a process observed both during the day and at night. Methylated furanoids comprise a large fraction of total furan emissions. Recent kinetic studies suggest that the NO3 initiated degradation of methylated furans is the dominant reaction pathway during nighttime, and with significant contribution on daytime. The aim of this study is to investigate the degradation products and the reaction mechanism of 2-methylfuran (2-MF) reaction with NO3 radicals using two atmospheric simulation chambers: CHARME (Chamber for the Atmospheric Reactivity and the Metrology of the Environment, Dunkerque, France) and THALAMOS (Thermally Regulated Atmospheric Simulation Chamber, Douai, France). All experiments were carried out at ambient temperature, (294 ± 2) K and atmospheric pressure (760 Torr, zero air). Oxidation products were qualitatively and quantitatively characterized using multiple, complementary detection techniques. Gas phase major and minor products were detected via offline GC-EI-MS (Gas chromatography - Electronic Impact - Mass Spectrometry) after trapping the gas-phase mixture on different adsorption media. PTR-ToF-MS (Proton Transfer Mass Reaction – Time of Flight – Mass Spectrometer, CHARME) and SIFT-MS (Selected Ion Flow Tube Mass Spectrometry, THALAMOS) were used on-line to monitor reactants and major products and to determine the end-product yields. 4-Oxo-2-pentenal (H(O)CCHCHC(O)CH3), and 2(5H)-furanone, 5-methyl, 5-nitrooxy ((CH3)C(ONO2)(C4H2O2)) were detected as major products with yields (62 ± 15) % and (26 ± 3) %, respectively. In-situ FTIR (Fourier Transform Infrared Spectroscopy) along with quantum mechanical molecular calculations revealed that organic nitrates and dinitrates were also formed. Secondary organic aerosols (SOA) formation, in the presence of ammonium sulfate seed, was also monitored using SMPS-CPC (Scanning Mobility Particle Sizer-Condensation Particle Counter). The size distribution and the mass concentration of the particles were determined for 2-MF concentration between 80 and 531 ppbv leading to SOA yields 1.03–2.23 %. Finally, SOA formed were chemically characterized using ESI-LC-QToF-MS/MS (Electrospray Ionization Liquid Chromatography – Quadrupole - Time of Flight - Tandem Mass Spectrometer) revealing that oligomers, e.g. highly oxygenated molecules (HOMs) were also formed. Based on our experimental observations, a reaction mechanism is proposed. NO3 radical is predominately added to the C2/C5 double bond of 2-MF, while the H atom abstraction channel, is estimated to be of minor importance. Results from this work provide detailed information about the NO3 radical initiated oxidation of 2-MF that can be used in chemical transport models to simulate the ageing processes occurring in biomass burning plumes.

DFT investigations of a copolymer of Dimeric Pyrrole and Dimeric 3-methyl furan

Conducting polymers are mainly used for the electronic applications, owing to its large surface area, good environmental stability, low cost, flexibility, and simplicity in synthesis. Among the conducting polymers, Dimeric Pyrrole and its copolymers are the most widely investigated and promising for commercial applications. Copolymerization is the best route to modify the conductivity of copolymers than their host polymers. The present work investigates the stability analysis and the electronic properties in terms of the HOMO-LUMO gap, DOS plot, and the electron density of dimeric Pyrrole, dimeric 3-methylfuran, and their copolymer using a density functional theory (DFT). We observed that the stability increases as the total energy in the copolymer of dimeric Pyrrole and dimeric 3-methylfuran decreases than its host dimers. The negative total energy confirms the stability of the copolymer than its host polymers. The electron density predicted the electron behavior of the atoms present in the system. As a result, we conclude that computationally synthesized copolymer with improved stability and better electronic properties (HOMO-LUMO gap, DOS profile, and electron density), maybe a better choice for the polymeric sensors sensor for drug molecules and their metabolic intermediates.

Understanding the Role of Base Species on Reversed Cu Catalyst in Ring Opening of Furan Compounds to 1, 2-Pentanediol.

The hydrogenation of biomass-derived furan compounds provides a sustainable pathway for the production of various valuable chemicals; product selectivity among multiple reaction pathways of furan compound hydrogenation is crucially dependent on catalytic sites; however controlling reaction pathways remains challenging due to the lack of identification and understanding of active sites. In this work we reveal the role of base sites in furfural selective hydrogenation through deliberately designed and synthesized reversed catalysts, basic metal oxides and hydroxide on Cu. It is demonstrated that base species greatly enhanced the selectivity of 1, 2-pentanediol (1, 2-PeD) from furfural, presenting a nearly fourfold increase of 1, 2-PeD: methyl furan ratio over the Cu based reverse catalysts. A combination of infrared spectroscopy and DFT calculations demonstrates the strong interaction between the C-O-C bond in furan ring and the catalyst surface in preferentially parallel adsorption mode in the presence of base species on Cu, thus facilitating the activation of C-O-C bond to produce 1, 2-PeD. This work provides a strategy of designing reversed catalyst to study the effect of promoters and reveals the role of base sites in the hydrogenation of biomass-derived furan compounds to diols.

Melamine-based porphyrin photosensitizer comprising sulphonic acid moieties for efficient aerobic oxidative acetalization of furfuryl alcohol: An access to octane booster under visible light

Furfuryl acetal has a pervasive significance in renewable energy resources that can be used as gasoline additives. In this protocol, oxidative acetalization of furfuryl alcohol was achieved by a novel melamine-based porphyrin photosensitizer comprising sulphonic acid (MPPsSA). The synthesized photocatalyst was scrutinized by XPS, NMR, FT-IR, and SEM/EDAX. The band gap (1.26 eV) and Hammett acidity (H0 = 0.987) of MPPsSA were determined by UV–Vis spectrophotometer. The photocatalyst was successfully employed for aerobic oxidative acetalization of furfuryl alcohols with alcohols (R-OH, R = C1-C6, C8) under irradiation of 5 W LED in a home-made photoreactor. All acetal derivatives were confirmed by 1H, 13C NMR, and GC–MS. Moreover, 2-(diethoxy methyl)furan exhibited octane booster with a 10% blend compared to commercial gasoline. The efficacy of the photocatalyst was sustainable up to sixth run and evidenced by FT-IR and FT-NMR. The gram scale acetalization, stability and recyclability of photocatalyst proven environmental benign protocol at ambient photocatalytic conditions.

Analytical (hydro)pyrolysis of pinewood and wheat straw in chloride molten salts: A route for 2-methyl furan production

2-methyl furan (MF) is a fuel additive with improved fuel characteristics compared to bio-ethanol. Unfortunately, the production of MF (from furfural (FF) hydrogenation) is not economically feasible. Interestingly, molten salts in biomass pyrolysis have shown to promote the formation of furans (mainly FF). Because molten salts hydropyrolysis could be an alternative route to both produce FF and convert it into MF, an assessment is indispensable. Molten salts pyrolysis and hydropyrolysis of pinewood and wheat straw and related model compounds were studied in a micro-reactor. The effect of hydropyrolysis process variables was assessed on the total detectable condensable vapors and MF formation.At low pressures (0.4 MPa), the chloride salts favored the production of FF and acetic regardless of the reaction atmosphere. Under a high pressure of hydrogen though (1.6 and 3.0 MPa), the conversion of FF to MF was enhanced through hydrogenation, hydrodeoxygenation and demethylation reactions. Molten salts hydropyrolysis at 350 °C and pressures of either 1.6 MPa (biomass mass fraction of 0.09) or 3.0 MPa (biomass mass fraction of 0.24) were optimal and yielded ca. 8 wt% to 9 wt% MF. Reaction temperatures >350 °C were unfavorable for the MF yield and instead promoted furfural decarbonylation to furan.

Production of 2-methyl furan, a promising 2nd generation biofuel, by the vapor phase hydrodeoxygenation of biomass-derived furfural over TiO2 supported Cu[sbnd]Ni bimetallic catalysts

This work investigates the vapor phase hydrodeoxygenation (HDO) of FFR to 2-MeF over a series of TiO2-supported mono and bimetallic Cu-Ni catalysts with a fixed Cu content (10 wt%) and varying Ni content (0–20 wt%). The catalysts were synthesized through a simple wet impregnation method, and their properties were studied in depth through an array of analytical techniques such as X-ray diffraction (XRD), H2-temperature programmed reduction (H2-TPR), Scanning Electron Microscopy (SEM), N2-physisorption, Raman spectroscopy, and NH3-temperature programmed desorption (TPD). The catalyst characterizations revealed that the addition of Ni in progressively larger amounts resulted in greater dispersion of Cu species and an increase in the surface area & porosity of the bimetallic catalysts, arising from the strong interactions between NiO and CuO species. Detailed studies were carried out to evaluate the effect of various process parameters such as Ni content, temperature, and contact time on the selectivity of 2-MeF. Ni content of the bimetallic catalysts and temperature played a significant role in product distribution than the contact time. The bimetallic catalyst with the composition 10%Cu-10%Ni was observed to be the optimum, providing a FFR conversion of 100%, and a 2-MeF selectivity of 84.5% at 200 °C, H2/FFR molar ratio = 15, and WHSV = 0.87 gFFR h−1 gcatalayst−1 after 6 h time-on-stream (TOS). During the long-term catalytic activity evaluation, the catalyst exhibited a stable 100% FFR conversion and ∼ 85% selectivity towards 2-MeF over a period of 12 h. Even after a period of 15 h, conversion and selectivity values remained >90% and 70%, respectively.

Ni-Mg/Al Mixed Oxides Prepared from Layered Double Hydroxides as Catalysts for the Conversion of Furfural to Tetrahydrofurfuryl Alcohol

Ni-Mg/Al mixed oxide catalysts (Ni2Al, Ni2Mg1Al, and Ni1Mg1Al) obtained from layered double hydroxides (LDHs) were tested on the one-pot production of tetrahydrofurfuryl alcohol (TFA) from furfural (FF). Upon calcination at 400 °C and reduction at 500 °C, the LDHs gave catalysts containing small nickel crystallites (<4 nm) dispersed on mixtures of metal oxides and spinel structures. Complete conversion of FF (>99.5%) was achieved on all the catalysts after 4 h at 190 °C and 5.0 MPa of H2 using 5 wt.% FF in ethanol and a furfural-to-catalyst mass ratio of 7.44 g/g. TFA evolved from the sequential hydrogenation of FF to furfuryl alcohol (FA) to TFA. Competing reaction routes involved decarbonylation of FF to furan (FUR) followed by hydrogenation to tetrahydrofuran (THF) or hydrogenolysis to n-butane (BU) and the hydrogenation of the carbonyl group in FF to form 2-methyl furan (mFUR) and its hydrogenation to 2-methyltetrahydrofuran (mTHF). A third competing route consisted of the nucleophilic addition of FF with ethanol and with FA to form acetals (such as 2-(diethoxymethyl)furan, FDA), which were later converted to difurfuryl ether (DFE) and tetrahydrofurfuryl ethyl ether (TFEE) as final products. Hydrogen pressure favored the production of TFA and diminished the formation of acetals, while temperature reduced the capacity of the catalyst to hydrogenate the furan ring, thus reducing TFA and increasing FA and FUR. An 80% yield to TFA was achieved with the Ni2Mg1Al catalysts after 6 h at 190 °C and 50 bar H2, but a variety of coproducts were present at low concentration. Testing of the catalysts in gas-phase hydrogenation conditions at atmospheric pressure revealed a poorer performance, with FA as the main product.

Understanding hydrogen pressure control of furfural hydrogenation selectivity on a Pd(1 1 1) model catalyst

We investigate the postulate that hydrogen pressure influences the furfural hydrogenation selectivity on palladium to form decarbonylation products at low hydrogen pressures, but 2-methyl furan at higher pressures. This change is caused by co-adsorbed hydrogen changing the orientation of adsorbed furfural; low hydrogen coverages favor flat-lying furfural, higher coverages form tilted species. This was tested for hydrogenation of furfural on a Pd(111) single crystal. The product distribution agreed with the postulate, with 100% selectivity to furan and tetrahydrofuran for low hydrogen pressures, with 2-methyl furan increasing with hydrogen pressure. The origin of the effect is explored using reflection–absorption infrared spectroscopy. This showed that co-adsorbed hydrogen influenced the orientation in a way predicted by theory. It was also found that other co-adsorbates displayed similar effects implying that a range of molecules in the reaction mixture could have significant effects on the furfural selectivity.

Simultaneous Oxidative Cleavage of Lignin and Reduction of Furfural via Efficient Electrocatalysis by P-Doped CoMoO4.

Electrochemical oxidative lignin cleavage and coupled 2-furaldehyde reduction provide a promising approach for producing high-value added products. However, developing efficient bifunctional electrocatalysts with noble-metal-like activity still remains a challenge. Here, an efficient electrochemical strategy is reported for the selective oxidative cleavage of Cα -Cβ bonds in lignin into aromatic monomers by tailoring the electronic structure through P-doped CoMoO4 spinels (99% conversion, highest monomer selectivity of 56%). Additionally, the conversion and selectivity of 2-furaldehyde reduction to 2-methyl furan reach 87% and 73%, respectively. In situ Fourier transform infrared and density functional theory analysis reveal that an upward shift of the Ed upon P-doping leads to an increase in the antibonding level, which facilitates the Cα -Cβ adsorption of the lignin model compounds, thereby enhancing the bifunctional electrocatalytic activity of the active site. This work explores the potential of a spinel as a bifunctional electrocatalyst for the oxidative cracking of lignin and the reductive conversion of small organic molecules to high-value added chemicals via P-anion modulation.

Analysis of Furan and Its Derivatives in Food Matrices Using Solid Phase Extraction Coupled with Gas Chromatography-Tandem Mass Spectrometry.

The objective of this study was to develop a simultaneous analysis method of furan and its 10 derivatives in different food commodities. The results indicated that furan and its 10 derivatives could be separated within 9.5 min by using a HP-5MS column and gas chromatography-tandem mass spectrometry (GC-MS/MS) with multiple reaction monitoring mode for detection. Furthermore, this method could resolve several furan isomers, such as 2-methyl furan and 3-methyl furan, as well as 2,3-dimethyl furan and 2,5-dimethyl furan. The most optimal extraction conditions were: 5 g of the fruit or juice sample mixed with 5 mL of the saturated NaCl solution, separately, or 1 g of the canned oily fish sample mixed with 9 mL of the saturated NaCl solution, followed by the equilibration of each sample at 35 °C for 15 min, using a carboxen-polydimethylsiloxane SPME arrow to adsorb the analytes for 15 min at 35 °C for subsequent analysis by GC-MS/MS. For method validation of all the analytes in the different food matrices, the recovery was 76-117% and the limit of the quantitation was 0.003-0.675 ng/g, while the relative standard deviation (RSD%) of the intra-day variability range from 1-16%, and that of the inter-day variability was from 4-20%. The method validation data further demonstrated that a reliable method was established for the analysis of furan and its 10 derivatives in commercial foods.

Unraveling the reaction mechanisms for furfural electroreduction on copper.

Electrochemical routes for the valorization of biomass-derived feedstock molecules offer sustainable pathways to produce chemicals and fuels. However, the underlying reaction mechanisms for their electrochemical conversion remain elusive. In particular, the exact role of proton-electron coupled transfer and electrocatalytic hydrogenation in the reaction mechanisms for biomass electroreduction are disputed. In this work, we study the reaction mechanism underlying the electroreduction of furfural, an important biomass-derived platform chemical, combining grand-canonical (constant-potential) density functional theory-based microkinetic simulations and pH dependent experiments on Cu under acidic conditions. Our simulations indicate the second PCET step in the reaction pathway to be the rate- and selectivity-determining step for the production of the two main products of furfural electroreduction on Cu, i.e., furfuryl alcohol and 2-methyl furan, at moderate overpotentials. We further identify the source of Cu's ability to produce both products with comparable activity in their nearly equal activation energies. Furthermore, our microkinetic simulations suggest that surface hydrogenation steps play a minor role in determining the overall activity of furfural electroreduction compared to PCET steps due to the low steady-state hydrogen coverage predicted under reaction conditions, the high activation barriers for surface hydrogenation and the observed pH dependence of the reaction. As a theoretical guideline, low pH (<1.5) and moderate potential (ca. -0.5 V vs. SHE) conditions are suggested for selective 2-MF production.

Cu/SiO2 synthesized with HKUST-1 as precursor: high ratio of Cu+/(Cu+ + Cu0) and rich oxygen defects for efficient catalytic hydrogenation of furfural to 2-methyl furan.

Cu/SiO2 is one of the most promising catalysts for the furfural (FF) hydrogenation reaction but suffers from the difficulty of tailoring the microstructure and surface properties. Herein, we developed a MOF-derived Cu/SiO2 catalyst (Cu/SiO2-MOF) for FF hydrogenation to 2-methyl furan (2-MF). In comparison with Cu/SiO2 catalysts prepared from ammonia evaporation (Cu/SiO2-AE) and traditional impregnation (Cu/SiO2-TI), the copper species in Cu/SiO2-MOF could not only be anchored on the silica surface via forming Cu-O-Si bonds but also exposed many more active sites. In this way, a higher ratio of Cu+/(Cu+ + Cu0) and richer oxygen defects were constructed via strong metal-support interactions, which were responsible for the superior catalytic performance. In addition, it was found that the solvent effect on product distribution played an important role in adjusting the selectivity to 2-MF and cyclopentanone (CPO). The present work not only provides a deep insight into the catalytic mechanism of Cu/SiO2-MOF for the FF hydrogenation reaction but also sheds light on the design and synthesis of highly efficient catalysts for other heterogeneous catalysis fields.

Frhodo: A program for simulating chemical kinetic measurements and optimizing kinetic mechanisms

Chemical kinetic simulations are frequently used to extract kinetic and mechanistic information from experimental data by fitting simulations to the data. For simple systems of consecutive single channel reactions this is a relatively straightforward task. However, as the complexity of the system increases and particularly for systems involving competitive multi-channel reactions manually optimizing a mechanism to obtain the best fits to a range of experimental data quickly becomes a time-intensive and challenging process, especially when rate coefficients have pressure and temperature dependencies. There is considerable potential for exploiting automated optimization methods to rapidly screen reaction mechanisms and optimize the fit by adjusting rate coefficients within well-defined constraints. A new chemical kinetics simulation program, Frhodo, has been developed for this purpose. The program allows either manual simulation of individual experiments or fully automated optimization against a range of experimental data by adjusting user selected reactions within user defined constraints. Frhodo incorporates machine learning-based optimization routines that work by either minimizing standardized residuals or through Bayesian parameter estimation. Frhodo's optimization capabilities are demonstrated by reexamining two previously studied systems of relevance to combustion. Dissociation of diacetyl followed by recombination of methyl radicals is an example of a sequence of single channel, consecutive reactions. Pyrolysis of 2-methyl furan exemplifies multi-channel, unimolecular reactions that are often encountered and have temperature and pressure dependencies in the rate coefficients of the channels and branching ratios between them. For both systems the optimization routines resulted in solutions similar to the original studies. Comments are made on the strengths and limitations of the approach.

The impact of post-harvest storage on sweet corn aroma

Fresh market sweet corn ( Zea mays L .) is a high sugar, high moisture vegetable that, due to its fast metabolic rate, is susceptible to rapid post-harvest decay at ambient temperatures. Immediate cooling and storage at low but not freezing temperatures are well established industry practices for maintaining post-harvest sugar content. Less is known about how post-harvest storage temperature impacts other important sweet corn consumer traits, such as aroma. In this study we measure the production and stability of the cooked sweet corn aroma compounds dimethyl sulfide, dimethyl disulfide, dimethyl trisulfide, 3-methyl furan, 3-methyl butanal and 2-methyl butanal. We reveal that these aroma compounds are also susceptible to post-harvest decay if sweet corn is stored at ambient rather than cool temperatures. Furthermore, the quantities and post-harvest decay rates of aroma volatiles vary among different sweet corn lines, indicating that sweet corn genetics can impact maintenance of post-harvest flavor. Some aroma compunds found in cooked sweet corn. • Low temperature post-harvest storage maintains sugar content of sweet corn. • Post-harvest storage also impacts the stability of cooked sweet corn aroma. • Sweet corn varieties can have different aroma profiles and post-harvest stability. • Genetic factors exist to improve the flavor related shelf life of sweet corn.

Exploiting the potential of cobalt molybdenum catalyst in elevated hydrodeoxygenation of furfural to 2-methyl furan

The key to achieving commercial production of fuels and chemicals from renewable sources is to find high-capability catalysts for selective conversion of biomass-based feed into the desired product(s). In this regard, having been screened, the molybdenum cobalt bimetal catalyst was found to be the best candidate for extremely elevated conversion of furfural in a highly selective manner to 2-methyl furan (2-MF). To approach the ideal catalytic activity, the Co-Mo needed to be optimally tuned. Although operating conditions should be optimized, the chemical composition and crystal structure of the catalyst were the two main determinant parameters for achieving the optimal catalyst. In this research, both the main problems of optimization of operating conditions and catalyst composition were emphasized. Operational pressure in all catalytic reactions was considered to be the ambient pressure (1 bar) being closer to the commercialization of this process. Operating temperature and weight hourly space velocity (WHSV) were the two main operational parameters for optimization. Since according to the principle of Sabatier, the best catalyst has “just right” interactions with either the reactants or products, the bimetal catalyst Co-Mo/Al2O3 with two different combinations was investigated for relatively high (Co-Mo/Al2O3 (1)) and relatively low acidic sites (Co-Mo/Al2O3 (2)). By adjusting the operational parameters, the best temperature was 300 °C, which achieved ideal conversion and selectivity of nearly 100 % in the lowest WHSV values. Under these conditions, the less acidic (relatively basic) catalyst, i.e., Co-Mo/Al2O3 (2) was best for catalytic hydrodeoxygenation (HDO) of the furfural to 2-MF.