Méthanol | EPFL Graph Search

Le méthanol (ou alcool méthylique, carbinol, alcool de bois, naphte de bois ou esprit de bois) est un composé organique de formule : CHOH (souvent abrégé en MeOH). C’est le plus simple des alcools. Il se présente sous la forme d'un liquide léger, volatil, incolore, inflammable, toxique ayant une odeur caractéristique, plus douce et sucrée que celle de l’éthanol (alcool éthylique). À température ambiante, ce liquide polaire sert d'antigel (pour liquide de refroidissement par exemple), de solvant, de carburant (en aéromodélisme ou en en) et comme dénaturant de l’alcool éthylique. Ces deux alcools restent néanmoins dissociables par distillation. En effet, la température d'ébullition de l'alcool méthylique n'est que de alors que celle de l'éthanol est de . Le méthanol sert aussi à produire le biogazole par réaction de transestérification. Le méthanol est naturellement produit par le métabolisme d'organismes anaérobies de nombreuses variétés de bactéries, ce qui explique une petite fra

Carbon dioxide hydrogenation to methanol at low pressure and temperature

The measurements obtained were used to investigates the methanol synthesis reaction from pure carbon dioxide and hydrogen over binary (CuO/ZrO2) and ternary supported catalysts (CuO/ZnO/Al2O3). A comparison of different catalysts is presented. The influence of the most important reaction parameters, i.e. temperature, pressure, space velocity and feed gas composition is examined at moderate temperatures (≤ 300 °C) and pressures (≤ 20 bar). The influence of the partial pressures of hydrogen, carbon dioxide, carbon monoxide, water and methanol are studied in detail with the most efficient catalyst. According to the results, water has a decisive effect on the catalyst activity and performance. The measured results were used to derive a possible Langmuir-Hinshelwood kinetic model of the methanol synthesis reaction. The catalyst surface is analyzed by in situ diffuse reflectance Fourier transform infrared spectroscopy. The identification and evolution of intermediates on CuO/ZnO/Al2O3 catalysts confirm that the reaction proceeds by prior formation of the carbonate on the copper, followed by hydrogenation of the carbonate to the formate and thereafter to methoxy and methanol. For CuO/ZrO2 catalysts results demonstrate that the methanol formation occurs via π – bound formaldehyde and methoxy. Responses of sine shape variation applied to the reactants are also examined. The conversion of CO2 with hydrogen to methanol is investigated in dielectric-barrier discharges with and without catalysts at low temperatures (≤ 100 °C) and pressures (≤ 10 bar). The combination of discharges and catalysts lower the activation energy of the reaction resulting in a decrease in the catalyst optimum temperature. The presence of the catalyst in the discharge increases the methanol yield and selectivity by more than a factor of 10. Electrochemical reduction of carbon dioxide is briefly investigated by using TiO2/Ni complex and TiO2/Ru complex thin film electrodes. A considerable decrease in overvoltage is achieved together with respectable current densities.

EPFL1998

Methanol production from CO(2)via an integrated, formamide-assisted approach

Paul Joseph Dyson, Aswin Gopakumar, Gunay Imanzade, Tim Pfister, Jorge Gustavo Uranga, Andreas Züttel

The synthesis of fuels from CO2 has made tremendous progress in recent years, although practical applications remain limited. Herein, we describe a cyclic process that produces MeOH from CO(2)via formamide intermediates, which are initially reduced using NaBH4 to form methanol and concomitantly release the corresponding amine, from which the formamide is subsequently regenerated in the presence of CO2/NaBH4. By tuning the substituents on the formamide/amine, the selectivity of both steps can be controlled, allowing the process to proceed in high yields, either in two separate steps or in a single step process. The observed trends in reactivity were rationalized with a resonance model of the formamide, which supports the observed trends in reactivity, and further consolidated by spectroscopy and calculations.

ROYAL SOC CHEMISTRY2020

Thermo-Economic Optimisation of Integrated Ethanol and Methanol Production in the Sugarcane Industry

Priscilla Caliandro, François Maréchal, Sandro Onorati, Emanuela Peduzzi, Adriano Viana Ensinas

The present paper evaluated a sugarcane biorefinery producing ethanol, through the conventional process by sugars fermentation and methanol through bagasse and leaves gasification, hot cleaning and synthesis. The sugarcane biorefinery was modelled using flowsheet modelling software and thermal integration. A thermo-economic model was developed in order to analyze the energy efficiency of the system as well as the total investment. Different configurations are analyzed for the methanol production process. Multi-objective optimization using a genetic algorithm solver is performed, allowing the analysis of several process configurations in terms of conflictive objectives energy efficiency and investment cost. The sugarcane biorefinery is self-sufficient in energy demand after thermal integration with a system energy efficiency increasing when the methanol production is higher, although it also leads to an increase in the total investment. Both Entrained Flow and Circulated Fluidized Bed gasification technologies are modelled and compared for sugarcane residues conversion, showing similar impacts in the system efficiency that can reach more than 55 % (dry biomass input low heating value basis), which is almost two fold higher than the one obtained in the traditional sugarcane ethanol plants currently in use.

Aidic Servizi Srl2014

Carbon dioxide hydrogenation to methanol at low pressure and temperature

EPFL1998