Methanol fuel volatility

Fuels cells are of interest both from energetic and environmental considerations. When methanol is fed directly to an anode, as in Direct Methanol Fuel Cells , electric power is generated, making the devices suitable for small and lightweight uses [53], Alternative fuels such as polyhydric alcohols like ethylene glycol and glycerol are much less volatile and toxic, on the one hand, and electrochemically oxidizable on the other [54]. Therefore, the electrochemical oxidation of various polyhydric alcohols has been investigated in acidic as well as in alkaline conditions. 

The construction of a cell permitting both FTIR measurements and electrochemical impedance measurements at buried polymer/metal interfaces has been described [266]. Ingress of water and electrolyte, oxidation (corrosion) of the aluminum metal layer, swelling of the polymer and delamination of the polymer were observed. A cell suitable for ATR measurements up to 80°C has been described [267]. The combination of a cell for ATR measurements with DBMS (see Sect. 5.8.1) has been developed [268]. It permits simultaneous detection of stable adsorbed species and relatively stable adsorbed reaction intermediates (via FTIR spectroscopy), quantitative determination of volatile species with DBMS and elucidation of overall reaction kinetics. An arrangement with a gas-fed electrode attached to the ATR element and operated at T = 60°C has been reported [269]. In this study, the establishment of mixed potentials at an oxygen consuming direct methanol fuel cell in the presence of methanol at the cathode was investigated. With infrared spec-... 

The following three sections of this chapter examine how the vapor pressure varies with composition when both components of a mixture are volatile and how that information can be used to separate them by distillation. Distillation, which we first encountered in Section G, is used to separate the many compounds that make up petroleum and to purify alternative fuels such as ethanol and methanol. 

In recent decades, direct alcohol fuel cells (DAFCs) have been extensively studied and considered as possible power sources for portable electronic devices and vehicles in the near future. The application of methanol is limited due to its high volatility and toxicity, although it is relatively easily oxidized to CO2 and protons. So other short chain organic chemicals especially ethanol, ethylene glycol, propanol, and dimethyl... 

Methyl Tertiary Butyl Ether (MTBE) An ether manufactured by reacting methanol and isobutylene. The resulting ether has high octane and low volatility. MTBE is a fuel oxygenate and is permitted in unleaded gasoline up to a level of 15% by volume. 

Charcoal was a valued commodity in antiquity. The ancient Egyptians used the volatile product of hardwood distillation, pyroligneous acid, for embalming. Before synthetic organic chemistry became well established, destructive hardwood distillation provided several important industrial chemicals, among these were acetone, acetic acid, and methanol (still often referred to as wood alcohol). Charcoal is a fine, smokeless fuel, prized for its smokeless nature and used extensively for outdoor cooking. Acetone was originally made by the dry distillation of calcium acetate made from wood-derived acetic acid, but better, cheaper sources are also available. 

There are over 70 alcohols in the atmosphere as a result of biogenic and anthropogenic emissions [67]. For example methanol and ethanol [68-70] have been used as fuels additives to reduce automobile emissions of carbon monoxide and hydrocarbons [71], in particular ethanol has been used in Brazil as a fuel for over 20 years [72]. 1-Propanol is widely used as a solvent in the manufacturing of different electronic components. The high volatility of these compounds causes their relative abundance in the troposphere and makes it relevant to determine their degradation pathways. During daytime the major loss process for alcohols is their reaction with OH radicals [68]. Accordingly, several experimental [69,70,73-84] and theoretical [85-88] kinetic studies of alcohols -F OH reactions have been performed. 

The butanols and their methyl and ethyl ethers have several advantages as oxygenates over methanol and ethanol in gasoline blends. Their energy contents are closer to those of gasoline the compatibility and miscibility problems with petroleum fuels are nil excessive vapor pressure and volatility problems do not occur and they are water tolerant and can be transported in gasoline blends by pipeline without danger of phase separation due to moisture absorption. Fermentation processes (Weizmann process) have been developed for simultaneous production of 1-butanol, 2-propanol, acetone, and ethanol from... 

ETBE (ethanol tertiary butyl ether, CgH, 0, density = 760 kg/m, LHV = 36 MJ/kg) is a better ingredient than bioethanol because it is not so volatile, not so corrosive, and has less affinity for water. ETBE-15 fuel is a blend of gasoline with 15% in volume of ETBE. ETBE is obtained by catal5dic reaction of bioethanol with isobutene (45%/55% in weight), noting that isobutene comes from petroleum. The other gasoline-substitute ether, MTBE (methanol tertiary butyl ether, (CH3)3-CO-CH3), is a full petroleum derivate (65% isobutene, 35% methanol). 

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