Stoichiometric volume

Fuel Heat of Combustion (288 K, 1 atm) (MJIm ) Stoichiometric Volume Ratio (%) Heat of Combustion Stoichiometrically Mixed with Air (MJ/m )... 

The chiral ligand was in all cases (2S,4S)-N-tert-butoxycarbonyl-4-diphenylphos-phino-2-diphenylphosphinomethylpyrrolidine (BPPM) and the catalyst was formed in an in situ system of [Rh(COD)2] BFT The asymmetric hydrogenation is well investigated in organic solvents like methanol, but the presence of water usually causes loss of activity and enantioselectivity because of the low solubility of both the catalyst and the substrate in water [27, 29]. The addition of low-molecular surfactants or commercially available polymeric amphiphiles increases the activity (here given as time of consumption of half the stoichiometric volume of hydrogen, t/2) as well as the enantioselectivity [4]. Tab. 6.1 summarizes selected experiments with different polymeric amphiphiles. 

The reduced intensities i(s) are calculated with respect to a given stoichiometric volume of the solution according to... 

The Pilling-Bedworth relation is not commonly known. Consider the solid-phase transformation aA Cgi —>bB Cg2. The relation of the stoichiometric volume of solid phase B to that of solid phase A can be expressed as APB = bVBlaVa = bMBppJaMpjyB. When ApB > 1 the solid-phase reaction proceeds with an increase of the solid phase volume, and vice versa. The latter situation is illustrated in Figure 5 for dry and wet stages of synthesis. 

Table 1. The composition (mol dm ), stoichiometric volume V per cadmium atom, and density p of the sample solutions...

The reduced intensities r(s) multiplied by s for solutions A to D are shown in Fig. 1. Figure 2 depicts the differential radial distribution curves, D(r) - 4jtr2po, where po represents the average scattering density in the stoichiometric volume V per cadmium atom. 

Formula 7.53 gives a very simple and satisfactory method for calculating the instantaneous value of e whenever it is needed. However, once the virtue of using inerts for this calculation has been noted, the question arises whether s is the best method of accounting for volume expansion, and hence if it is needed at all. The traditional uses for e are in formulas for conversion fractions, as in equations 7.34 - 7.36 above, and in the reaction rate expression where terms like (1 + ex) are introduced to account for stoichiometric volume expansion (see for example O. Levenspiel (1999) third edition,... 

One of the traditional uses fix e is in rate expressions where terms like (1+ex) are introduced to account for stoichiometric volume expansion. These cases can be easily handled by the above method of calculation of volume expansion using the presence of inerts in the feed to calculate e. For example, in Levenspiel (1999), pp. 69-72, it is... 

Hydrolysis is avoided in nonaqueous media, when ethanolic solutions of copper(II) nitrate (water free) and lithium azide are mixed to precipitate the black-brown copper(II) azide [181]. Likewise, stoichiometric volumes of sodium azide and copper(II) perchlorate, in acetone containing 10% (v/v) water, may be added slowly to a large volume of acetone. A red precipitate of acetone-solvated copper(II) azide is obtained, which after washing is dried at llO C to obtain the free azide (color change to brown) [184]. Similarly, the azide has been precipitated by mixing alcoholic solutions of hydrazoic acid and copper acetate [185]. 

Recently the Lewis acid-catalysed oxidation of isobutane has been re-examined with the rigorous exclusion of any Bronsted acid and stoichiometric volumes of hydrogen were collected. When the temperature of a solution of isobutane in SbF5/S02ClF was raised to — 30 °C, hydrogen evolved and the t-butyl cation was produced quantitatively. Analysis of a white precipitate showed SbF3 to have been formed (equation 9). When the reaction was carried out in the presence of acetone, then only traces of hydrogen were detected and equimolar quantities of the t-butyl cation and protonated acetone formed (equation 10). 

The above equation indicates complete combustion of the fuel gas methane. The volume of air required for the complete theoretical combustion of a gas (such as methane) is called the stoichiometric volume (100%). A flame containing an excess (>1(X)% stoichiometry) of air is referred to as an oxidizing flame a flame that does not have sufficient air (<100% stoichiometry) to complete combustion is a reducing flame. 

Peregrine Phillips British patent 6096 (1881) described process of forming sulfur trioxide with a platinum catalyst. Used stoichiometric volumes of sulfur dioxide and oxygen. Inspired further research. 

Thann Chemical Works, Alsace Acquired an improved oleum process design from Squire. Burned Sicilian sulfur and washed gas at 4 atm pressure. Mixed SOrwith stoichiometric volume of air and formed SO3 using platinized asbestos. Output 1.5 tons of SO3 per day and dissolved in concentrated H2SO4. 

The modem two-step process converts hydrogen sulfide mixed with a stoichiometric volume of air to sulfur. In theory, one-third of the hydrogen sulfide is oxidized to sulfur dioxide in a carefully designed furnace, while the remaining hydrogen sulfide reacts with the sulfur dioxide to produce sulfur in two or more reactors containing a suitable catalyst. 

Oxygen or hydrogen can be removed from inert gas streams by the addition of stoichiometric volumes of hydrogen or oxygen, respectively. Not surprisingly, the catalyst can also be used to remove traces of sulfur from gas streams. More than 10 wt% of sulfur can be absorbed by the catalyst at about 300 C. 

In the Wacker two-stage process, the ethylene was completely oxidized with palladium chloride/cupric chloride solution at 110°C and 10 bar, with the stoichiometric volume of air in the reaction vessel. Acetaldehyde was recovered from the circulating solution and the palladium oxidized with air at lOO C and 100 bar pressme in a second vessel before the catalyst solution was letumed to the reactor. 

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