Alcohols Ethanol Methanol

Benzol and other alcohol-hased additives improved octane number, up to a point. Experiments using alcohol (ethanol, methanol) as a replacement for gasoline began as early as 1906. In 1915, Hetu-y Ford announced a plan to extract alcohol from grain to power his new Fordson tractor, an idea that never achieved commercial success. 

The method of revealing of H-bonds is very simple an addition of low concentration, 1-3% of molar fraction, of alcohols (ethanol, methanol) to the solution in neutral solvent (CH, for example) results in a substantial spectral shift. Further addition of alcohols, up to 100%, gives much smaller shifts. A small percentage of alcohol may cause 50-80% of total spectral shift. Upon addition of the trace quantities of alcohol, one sees that the intensity of the initial spectrum is decreased, and new red-shifted spectrum appears. The appearance of new spectral component is a characteristic of specific solvent effects. Because the specific spectral shifts occur only at low concentration of alcohol, this effect is probably attributed to H-bonding to electronegative group in the molecule. The next experiment, which can support this conclusion, is an addition of aprotic solvent, for example,... 

The sensors based on hetero-junction oxide structures show considerable response in alcohol (ethanol, methanol) media. The hetero-junction between oxide and solid solution phases appear to be very active in a course of both adsorption and oxidation of alcohol. 

The temperature range for liquid ammonia is from -78 to -33°C. The temperature range for liquid methyl alcohol is from -94 to - -65°C. The parameter surface tension for ammonia and alcohol (ethanol, methanol) is only 1/3 that of water. 

In a conventional gasoline containing hydrocarbons or even ethers, the presence of water is not a problem in fact, water is totally soluble up to about 50 ppm at ambient temperature. Beyond this value water separates without affecting the hydrocarbon phase and the water leg can be withdrawn if necessary. On the other hand, in the presence of alcohols (ethanol and especially methanol), trace amounts of water can cause a separation of two phases one is a mixture of water and alcohol, the other of hydrocarbons (Cox, 1979). 

PMMA is not affected by most inorganic solutions, mineral oils, animal oils, low concentrations of alcohols paraffins, olefins, amines, alkyl monohahdes and ahphatic hydrocarbons and higher esters, ie, >10 carbon atoms. However, PMMA is attacked by lower esters, eg, ethyl acetate, isopropyl acetate aromatic hydrocarbons, eg, benzene, toluene, xylene phenols, eg, cresol, carboHc acid aryl hahdes, eg, chlorobenzene, bromobenzene ahphatic acids, eg, butyric acid, acetic acid alkyl polyhaHdes, eg, ethylene dichloride, methylene chloride high concentrations of alcohols, eg, methanol, ethanol 2-propanol and high concentrations of alkahes and oxidizing agents. 

The principal solvents that have been used are alcohols such as ethanol, methanol, and propanol, and organic acids such as formic or acetic acid, but other solvents iaclude esters, ethers, phenols, cresols, and some amines. Even solvents such as CO2 and NH in the supercritical fluid state have been tried as solvents. 

Methyl ethyl ketone Higher ketones Methanol Motor alcohol Ethanol... 

Sodium cyanide is soluble in Hquid ammonia. At temperatures below —31°C, sodium cyanide pentaammoniate [69331-34-6] NaCN-5NH3, separates in large flat crystals. At 15°C, 100 g anhydrous methanol dissolves 6.44 g anhydrous sodium cyanide at 67.4°C, it dissolves 4.10 g. Sodium cyanide hemihydrate [69331 -35-7] NaCNO.5 H2O, has been obtained by recrystaUization from cold 85% alcohol. The system NaCN—NaOH—H20 has been studied (48,49). Sodium cyanide is slightly soluble in formamide, ethanol, methanol, SO2, furfural, and dimethylformamide. 

On the base of alcohol oxidase and flavocytochrome b, the enzymatic kits for selective assay of ethanol, methanol, formaldehyde and L-lactate were developed. 

Potassium borohydride is similar in properties and reactions to sodium borohydride, and can similarly be used as a reducing agent for removing aldehydes, ketones and organic peroxides. It is non-hygroscopic and can be used in water, ethanol, methanol or water-alcohol mixtures, provided some alkali is added to minimise decomposition, but it is somewhat less soluble than sodium borohydride in most solvents. For example, the solubility of potassium borohydride in water at 25° is 19g per lOOmL of water (as compared to sodium borohydride, 55g). 

The most versatile derivative from which the free base can be readily recovered is the picrate. This is very satisfactory for primary and secondary aliphatic amines and aromatic amines and is particularly so for heterocyclic bases. The amine, dissolv in water or alcohol, is treated with excess of a saturated solution of picric acid in water or alcohol, respectively, until separation of the picrate is complete. If separation does not occur, the solution is stirred vigorously and warmed for a few minutes, or diluted with a solvent in which the picrate is insoluble. Thus, a solution of the amine and picric acid in ethanol can be treated with petroleum ether to precipitate the picrate. Alternatively, the amine can be dissolved in alcohol and aqueous picric acid added. The picrate is filtered off, washed with water or ethanol and recrystallised from boiling water, ethanol, methanol, aqueous ethanol, methanol or chloroform. The solubility of picric acid in water and ethanol is 1.4 and 6.23 % respectively at 20°. 

Liver alcohol dehydrogenase (ADH) is relatively nonspecific and will oxidize ethanol or other alcohols, including methanol. Methanol oxidation yields formaldehyde, which is quite toxic, causing, among other things, blindness. Mistaking it for the cheap... 

Some organic compounds can be in solution with water and the mixture may still be a flammable mixture. The vapors above these mixtures such as ethanol, methanol, or acetone can form flammable mixtures with air. Bodurtha [39] and Albaugh and Pratt [47] discuss the use of Raoult s law (activity coefficients) in evaluating the effects. Figures 7-52A and B illustrate the vapor-liquid data for ethyl alcohol and the flash point of various concentrations, the shaded area of flammability limits, and the UEL. Note that some of the plots are calculated and bear experimental data verification. 

Oxygen was added as oxygenated hydrocarbon components methyl tert-butyl ether (MTBE), tert-amyl methyl ether (TAME), ethyl tert-butyl ether (ETBE), di-isopropyl ether (DIPE), ethanol, methanol, and tertiary butyl alcohol (TBA). The properties of oxygenates, as they relate to gasoline blending, are shown in Table 10-1. 

Compounds with a smaller/C., and larger pKa are less acidic, whereas compounds with a larger/Ca and smaller plsimple alcohols like methanol and ethanol are about as acidic as water but substituent groups can have a significant effect, tert-Butyl alcohol is a weaker acid, for instance, and 2,2,2-trifluoroethanol is stronger. Phenols and thiols, the sulfur analogs of alcohols, are substantially more acidic than water. 

These four solvents can thus be termed protogenic solvents, whilst bromine trifluoride and sulphur dioxide which do not contain hydrogen are non-protonic solvents. Non-ionising solvents include hydrocarbons, ethers, esters and higher alcohols the lower alcohols, especially methanol and ethanol, do show slight ionising properties with appropriate solutes. 

Acetone, THF, methanol, ethyl acetate, isopropyl acetate, isopropyl alcohol, ethanol, n-propyl alcohol, toluene, and 2-methoxyethanol... 

Ethanol, CH3CH2OH (4), the alcohol of beer and wine, is an ethane molecule in which one H atom has been replaced by an —OH group, and CH3OH (5) is the toxic alcohol called methanol, or wood alcohol. 

Figure 7. Dependence of the fluorescence quamum yield of BMPC on solvent viscosity ( ) in linear alcohols, from methanol to dccanol, at 25°C, (o) in absolute ethanol between 200 and 298 K. The quantum yields were measured on optically thin samples (Am <0.2). The value in ethanol, 5.7x10, was determined relative to quinine sulfate in 0.5 mol 1" HjSO ((j)p=0.55 [62]) and 9,10-diphenylanthracene in cyclohexane (4ip=0.90 [63]). It was then used as a reference for the determinations in the other alcohols.

With the complex where L = pyridine an optical nanosensor was developed [135-137], the method used to fix the vapochromic material to the optical fiber was the electrostatic self assembling method (ESA) and the light source used was an 850 nm LED. The sensor was tested for two different alcohols (ethanol and methanol) and it was possible to distinguish between different concentrations. It was also possible to discriminate between the two different alcohols. 

The use of ethanol as an achiral auxiliary gave the adduct 53 with 55% ee, while neopentyl alcohol and methanol gave 96 and 87% ee, respectively. These results suggested that the achiral alcohol might exert a steric effect on the stereoselectivity. However, the increase in enantioselectivity from 55% to about 96% when 2,2,2-trifluoroethanol (TFE) was used instead of ethanol indicates a possible significant inductive effect also. Good enantioselectivities were also obtained with carboxylic acids and phenols. 

Methylene chloride is probably the most generally used solvent for decaffeination processes, but others, some of which are already found in small amounts in coffee beans, are coming into use. For example, ethyl acetate,8 formaldehyde-dimethylacetal, ethanol, methanol, acetone,9 propane,10 benzyl alcohol,11 carbon dioxide,12 and supercritical carbon dioxide with an acid13 are used. Generally the pressure and temperature of the system are adjusted to keep the solvent in the liquid state. Coffee oil itself is even described for this use in one patent.14... 

The simplest alcohol is methanol, CH,OH, also called methyl alcohol in a less systematic system of naming. Methanol is also known as wood alcohol. Ethanol, CH3CH2OH, also known as ethyl alcohol or grain alcohol, is the principal constituent of intoxicating beverages. Other alcohols of importance are included in Table 21-5. Note that the systematic names of alcohols characteristically end in -ol. 

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