Methanol potential

Allis, J.W., Brown, B.L., Simmons, J.E., Hatch, G.E., McDonald, A. House, D.E. (1996) Methanol potentiation of carbon tetrachloride hepatotoxicity the central role of cytochrome P450. Toxicology, 112, 131-140... 

Cantilena, L.R., Cagen, S.Z. Klaassen, C.D. (1979) Methanol potentiation of carbon tetrachloride-induced hepatotoxicity. Proc. Soc. exp. Biol. Med., 162, 90-95... 

The results of one such example are shown in Figure 6 using the scaled methanol potential and quantum-mechanically derived potentials for acetonitrile and their cross interaction. These results are true predictions from the combination of quantum mechanics and molecular simulation. No parameters have been adjusted to... 

For the foreseeable future, methyl tertiary butyl ether is expected to provide for the greatest demand for methanol (unless the MTBE is banned from gasoline). Utilization of methanol directly as automotive fuel has not found strong support except in specialized uses such as racing vehicles. However, research is progressing to develop other uses for methanol. Potentially large new markets for methanol may be the following ... 

To eliminate the effect of adsorbed CO formed from methanol dissociation on the bulk oxidation of methanol, potential step amperometric experiments on Ru-modified smooth polycrystalline Pt, Pt(l 11), and Pt(332) have been carried out. The effect of potential on the steady-state currents and current efficiencies for CO2 formation are shown in Fig. 8. For methanol oxidation on Ru-modified smooth polycrystalline Pt (pc-Pt/Ru), the Faradaic current monotonically increases from +0.5 to +0.7 V. The current efficiency for CO2 is much higher than that on pc-Pt for potentials of <0.65 V, i.e., ca. 52% vs. <20% however, it decreases for potentials higher than +0.65 V, again due to the formation of inactive Ru oxide. For example, at +0.7 V, the current efficiency for CO2 generation for pc-Pt/Ru is similar to that on pc-Pt. At +0.65 V, the Faradaic current is a bit smaller on Pt(l 11)/Ru than oti Pt(lll), while the formation of CO2 increases markedly and the current efficiency of CO2 reaches about 100%, compared to 21% on Pt(lll). Compared to Pt(332), the Faradaic current is significantly reduced on Pt(332)/Ru at +0.65 V due to the blockage of step sites by Ru adatoms. However, the formation of CO2 increases somewhat and the current efficiency of CO2 reaches about 61%, compared to 22%... 

Suntana, A.S., Vogt, K.A., Tumblom, E.C., Upadhye, R., 2009. Bio-methanol potential in Indonesia forest biomass as a source of bio-enagy that reduces carbon emissions. Applied Energy 86 (Suppl. 1), S215—S221. 

Hydrogen storage in hydrogen rich liquid methanol (potentially from renewable sources - potentially with very low emissions). 

Momany F A 1978 Determination of partial atomic charges from ab initio molecular electrostatic potentials. Application to formamide, methanol and formic acid J. Phys. Chem. 82 592... 

FIGURE 4 2 Electro static potential maps of methanol and chloro methane The electrostatic potential is most negative near oxygen in methanol and near chlorine in chloromethane The most positive region is near the O—H proton in methanol and near the methyl group in chloromethane... 

The S—H bond is less polar than the O—H bond as is clearly seen m the elec trostatic potential maps of Figure 15 7 The decreased polarity of the S—H bond espe cially the decreased positive character of the proton causes hydrogen bonding to be absent m thiols Thus methanethiol (CH3SH) is a gas at room temperature (bp 6°C) whereas methanol (CH3OH) is a liquid (bp 65°C)... 

FIGURE 15 7 Electrostatic potential maps of (a) methanol and (b) methanethiol The color scales were adjusted to be the same for both molecules to allow for direct comparison The development of charge is more pronounced in the region surrounding the —OH group in methanol than it is for the —SH group in methanethiol... 

Size density surface (top left) space filling model (top right) potential map (bottom left) and tube model (bottom right) for methanol... 

The use of an amperometric detector is emphasized in this experiment. Hydrodynamic voltammetry (see Chapter 11) is first performed to identify a potential for the oxidation of 4-aminophenol without an appreciable background current due to the oxidation of the mobile phase. The separation is then carried out using a Cjg column and a mobile phase of 50% v/v pH 5, 20 mM acetate buffer with 0.02 M MgCl2, and 50% v/v methanol. The analysis is easily extended to a mixture of 4-aminophenol, ascorbic acid, and catechol, and to the use of a UV detector. 

It is therefore more relevant to examine wodd resources of natural gas in judging the supply potential for methanol. Wodd proved reserves amount to approximately 1.1 x 10 (40,000 TCF) (11). As seen in Figure 1, these reserves are distributed more widely than oil reserves. 

In the late 1980s attempts were made in California to shift fuel use to methanol in order to capture the air quaHty benefits of the reduced photochemical reactivity of the emissions from methanol-fueled vehicles. Proposed legislation would mandate that some fraction of the sales of each vehicle manufacturer be capable of using methanol, and that fuel suppHers ensure that methanol was used in these vehicles. The legislation became a study of the California Advisory Board on Air QuaHty and Fuels. The report of the study recommended a broader approach to fuel quaHty and fuel choice that would define environmental objectives and allow the marketplace to determine which vehicle and fuel technologies were adequate to meet environmental objectives at lowest cost and maximum value to consumers. The report directed the California ARB to develop a regulatory approach that would preserve environmental objectives by using emissions standards that reflected the best potential of the cleanest fuels. 

T. B. BlaisdeU, M. D. Jackson, and K. D. Smith, "Potential of Light-Duty Methanol Vehicles," SAE Paper 891667, SAE Euture Transportation Technology Conf. andExpo. (Vancouver, Canada, Aug. 7—10,1989), Society of Automotive Engineers, Warrendale, Pa. 

By selection of appropriate operating conditions, the proportion of coproduced methanol and dimethyl ether can be varied over a wide range. The process is attractive as a method to enhance production of Hquid fuel from CO-rich synthesis gas. Dimethyl ether potentially can be used as a starting material for oxygenated hydrocarbons such as methyl acetate and higher ethers suitable for use in reformulated gasoline. Also, dimethyl ether is an intermediate in the Mobil MTG process for production of gasoline from methanol. 

Other potential processes for production of formic acid that have been patented but not yet commerciali2ed include Hquid-phase oxidation (31) of methanol to methyl formate, and hydrogenation of carbon dioxide (32). The catalytic dehydrogenation of methanol to methyl formate (33) has not yet been adapted for formic acid production. 

Synthesis Gas Generation Routes. Any hydrocarbon that can be converted into a synthesis gas by either reforming with steam (eq. 4) or gasification with oxygen (eq. 5) is a potential feedstock for methanol. 

Direct conversion of methane [74-82-8] to methanol has been the subject of academic research for over a century. The various catalytic and noncatalytic systems investigated have been summarized (24,25). These methods have yet to demonstrate sufficient advantage over the conventional synthesis gas route to methanol to merit a potential for broad use. 

Denitrification of wastewater in treatment plants offers another potential use for methanol. There are a few such plants in the world however, this use is not expected to grow appreciably, as there are more proven methods for nitrogen removal commercially available. 

The advent of a large international trade in methanol as a chemical feedstock has prompted additional purchase specifications, depending on the end user. Chlorides, which would be potential contaminants from seawater during ocean transport, are common downstream catalyst poisons likely to be excluded. Limitations on iron and sulfur can similarly be expected. Some users are sensitive to specific by-products for a variety of reasons. Eor example, alkaline compounds neutralize MTBE catalysts, and ethanol causes objectionable propionic acid formation in the carbonylation of methanol to acetic acid. Very high purity methanol is available from reagent vendors for small-scale electronic and pharmaceutical appHcations. 

Poly(ethylene oxide) associates in solution with certain electrolytes (48—52). For example, high molecular weight species of poly(ethylene oxide) readily dissolve in methanol that contains 0.5 wt % KI, although the resin does not remain in methanol solution at room temperature. This salting-in effect has been attributed to ion binding, which prevents coagulation in the nonsolvent. Complexes with electrolytes, in particular lithium salts, have received widespread attention on account of the potential for using these materials in a polymeric battery. The performance of soHd electrolytes based on poly(ethylene oxide) in terms of ion transport and conductivity has been discussed (53—58). The use of complexes of poly(ethylene oxide) in analytical chemistry has also been reviewed (59). 

Like brines, alcohols were readily available and widely used as antifreeze Hquids in the early 1900s. Both methanol and ethanol offer exceUent heat transfer and efficient freeze point depression. However, the alcohols have the distinct disadvantage of their low boiling points. During the summer months when the engines operate hot, significant amounts of the alcohols are lost because of evaporation. These evaporative losses result in cosdy make-up requirements. Additionally, the alcohols have very low flash points and potentially flammable vapors. These safety concerns have, particularly in recent years, caused the use of alcohols to be completely discontinued for most heat-transfer systems. 

Pirmenol. Pirmenol hydrochloride, a pyridine methanol derivative, is a racemic mixture. It has Class lA antiarrhythmic activity, ie, depression of fast inward sodium current, phase 0 slowing, and action potential prolongation. The prolongation of refractory period may be a Class III property. This compound has shown efficacy in converting atrial arrhythmias to normal sinus rhythm (34,35). 

The performance of many metal-ion catalysts can be enhanced by doping with cesium compounds. This is a result both of the low ionization potential of cesium and its abiUty to stabilize high oxidation states of transition-metal oxo anions (50). Catalyst doping is one of the principal commercial uses of cesium. Cesium is a more powerflil oxidant than potassium, which it can replace. The amount of replacement is often a matter of economic benefit. Cesium-doped catalysts are used for the production of styrene monomer from ethyl benzene at metal oxide contacts or from toluene and methanol as Cs-exchanged zeofltes ethylene oxide ammonoxidation, acrolein (methacrolein) acryflc acid (methacrylic acid) methyl methacrylate monomer methanol phthahc anhydride anthraquinone various olefins chlorinations in low pressure ammonia synthesis and in the conversion of SO2 to SO in sulfuric acid production. 

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