Decane pressure

Decane-1 10-dicarboxylic acid from sebacic acid. Convert sebacic acid into the acid chloride by treatment with phosphorus penta-chloride (2 mols) and purify by distillation b.p. 146-143°/2 mm. the yield is almost quantitative. Dissolve the resulting sebacoyl chloride in anhydrous ether and add the solution slowly to an ethereal solution of excess of diazomethane (prepared from 50 g. of nitrosomethylurea) allow the mixture to stand overnight. Remove the ether and excess of diazomethane under reduced pressure the residual crystalline 1 8-bis-diazoacetyloctane weighs 19 -3 g. and melts at 91° after crystaUisation from benzene. 

A solution of 12.5 g (0.088 mole) of l,4-dioxaspiro[4.5]decane (Chapter 7, Section IX) in 200 ml of anhydrous ether is added to the stirred mixture at a rate so as to maintain a gentle reflux. (Cooling in an ice bath is advisable.) The reaction mixture is then refluxed for 3 hours on a steam bath. Excess hydride is carefully destroyed by the dropwise addition of water (1-2 ml) to the ice-cooled vessel until hydrogen is no longer evolved. Sulfuric acid (100 ml of 10% solution) is now added followed by 40 ml of water, resulting in the formation of two clear layers. The ether layer is separated and the aqueous layer extracted with three 20-ml portions of ether. The combined ethereal extracts are washed with saturated sodium bicarbonate solution followed by saturated sodium chloride solution. The ethereal solution is dried over anhydrous potassium carbonate (20-24 hours), filtered, and concentrated by distillation at atmospheric pressure. The residue is distilled under reduced pressure affording 2-cyclohexyloxy-ethanol as a colorless liquid, bp 96-98°/ 3 mm, 1.4600-1.4610, in about 85% yield. 

A mixture of 10.5 g of 1,4steam bath for 4 hours during which 2.0 g of methylmercaptan was collected in a dry ice bath connected to the reaction flask through a water cooled reflux condenser. The reaction mixture was then evaporated at 15 mm pressure to a solid residue which was then dissoived in 80 ml of 50/50 methanol-ethanol. The solution was filtered and evaporated to approximately 50 ml volume and allowed to cool and crystallize, giving a crop melting at 213.5°C to 215°C of 1,4[Pg.743]

I. F. Holscher, G. M. Schneider and J. B. Ott, "Liquid-Liquid Phase Equilibria of Binary Mixtures of Methanol with Hexane, Nonane, and Decane at Pressures up to 150 MPa", Fluid Phase Equilib., 27, 153-169 (1986). 

Reported vapor pressures of /7-decane at various temperatures and the coefficients for the vapor pressure ... 

FIGURE 2.1.1.1.26.1 Logarithm of vapor pressure versus reciprocal temperature for n-decane. 

Chirico, R.D, Nguyen, A., Steele, W.V., Strube, M.M. (1989) Vapor pressure of n-alkanes revisited. New high-precision vapor pressure data on ra-decane, ra-eicosane, and n-octacosane. J. Chem. Eng. Data 34, 149-156. 

Calculate the range of temperatures within which the vapor-air mixture above the liquid surface in a can of n-hexane at atmospheric pressure will be flammable. Data are found in Table 4.5. Calculate the range of ambient pressures within which the vapor/air mixture above the liquid surface in a can of n-decane (n-C10H22) will be flammable at 25 °C. 

Calculate the temperature at which the vapor pressure of n-decane corresponds to a stoichiometric vapor-air mixture. Compare your result with the value quoted for the firepoint of n-decane in Table 6.1. 

The crude product is dissolved in diethyl ether / petroleum ether (1 5) (5 mL) and poured onto a column (45-mm diameter) filled with 200 g of silica gel (Merck 230-400 mesh for flash chromatography). Elution (Note 23) under pressure (Note 14) with diethyl ether / petroleum ether (1 5) gives 2-oxo-5-methoxyspiro[5.4]decane as a colorless liquid (4.43 g 75%) (Note 24). 

Reduction of lactams to amines resembles closely the reduction of amides except that catalytic hydrogenation is much easier and was accomplished even under mild conditions. a-Norlupinone (l-azabicyclo[4.4.0]-2-oxodecane) was converted quantitatively to norlupinane (l-azabicyclo[4.4.0]decane) over platinum oxide in 1.25% aqueous hydrochloric acid at room temperature and atmospheric pressure after 16 hours [1122]. Reduction of the same compound by electrolysis in 50% sulfuric acid over lead cathode gave 70% yield [1122]. 

Two of the physical properties which are affected by temperature are vapor pressure and viscosity. The vapor pressure of n-decane approximately doubles with each rise of 10 C. This increase would double the evaporation rate and should, theoretically at least, halve the contact time of the hydrocarbon on the plant. The effects of injurious oils are closely correlated with the length of time they remain in or on the plant. Thus, consider-... 

The viscosity of oil has an important influence on the speed of entrance into the plant. As the viscosity decreases, the rate of penetration increases, as does the speed at which visible injury symptoms develop. Vapor pressure and viscosity curves for n-decane are given in Figure 2. If the two are of equal importance in hydrocarbon penetration, they would approximately cancel each other. Such a cancellation may explain the lack of a marked change in hydrocarbon toxicity with variations in temperature. 

Figure 2. Effect of Temperature on Vapor Pressure and Viscosity of n-Decane Formula and constants for calculation and a portion of the data from American Petroleum InsHtuto (I)...

Pavlovskaya, G., Semenova, M., Tsapkina, E., Tolstoguzov V. (1993). The influence of dextran on the interfacial pressure of adsorbing layers of 1 IS globulin Viciafaba at the planar w-decane/aqueous solution interface. Food Hydrocolloids, 7, 1-10. 

In line with the Gibbs adsorption equation (equation 3.33 in chapter 3), the presence of thermodynamically unfavourable interactions causes an increase in protein surface activity at the planar oil-water interface (or air-water interface). As illustrated in Figure 7.5 for the case of legumin adsorption at the n-decane-water interface (Antipova et al., 1997), there is observed to be an increase in the rate of protein adsorption, and also in the value of the steady-state interfacial pressure n. (For the definition of this latter quantity, the reader is referred to the footnote on p. 96.)... 

Figure 7.5 Effect of the character of the interactions between dextran and legunhn on the time-dependent interfacial pressure jc of the adsorbed layer of legumin at the planar o-decane-watcr interface (o) 0.001 wt% legumin alone, and ( ) 0.001 wt% legumin + 2 wt% dextran. (a) Thennodynanhcally unfavourable interaction pH = 7.0, ionic strength = 0.01 M (dextran A/w = 48 kDa). (b) Thermodynamically favourable interaction pH = 7.8, ionic strength = 0.01 M (dextran A/w = 270 kDa).

Figure 7.15 Effect of thermodynamically favourable interactions between biopolymers on protein surface activity at the planar oil-water or air-water interface. The surface pressure n reached after 6 hours is plotted against the polysaccharide concentration ( ), legumin (0.001 wt%) + dextran (Mw = 270 kDa) at / -decane-water surface at pH = 7.8 and ionic strength = 0.01 M, (Ay = -0.2 x 105 cm3 mol1) (Pavlovskaya et ah, 1993) ( ), legumin (0.001 wt%) + maltodextrin (MD6, Mw = 102 kDa) at air-water surface at pH = 7.2 and ionic strength = 0.05 M (Ay = - 0.02 x 105 cm3 mol-1) (Belyakova et ah, 1999) (A), legumin (0.001 wt%) + maltodextrin (MD10, Mw = 45 kDa) at air-water surface at pH = 7.2 and ionic strength = 0.05 M (.1 / = - 0.08 x 105 cm3 mol-1) (Belyakova et ah, 1999).

Figure 6 shows the isotherms of the samples using different alkanes as expander. Except the sample obtained with nonane, the adsorption-desorption isotherms of all other compounds are type IV, characteristic of mesoporous materials according to the BDDT classification [21], Isotherms can be decomposed in three parts the formation of the monolayer, a sharp increase characteristic of the capillary condensation of nitrogen within the mesopores and finally a plateau indicating the saturation of the samples. From pentane to decane the relative pressure at which the capillary condensation occurs, increases from 0 30 to 0.60, indicating that the value of the pore diameter increases when the alkane chain length is raised since the p/po position of the inflection point is related to the pore diameter. From undecane, this value decreases to reach 0.40 for dodecane We can conclude that the value of the pore diameter drops from decane to dodecane... 

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