Carbon monoxide, separation vapor pressure

Figure 1 shows the vapor pressure of some of the relevant compounds as a function of temperature. At -230.8°F and -184°F, the vapor pressure of propane is about 0.1 mm Hg and 1 mm Hg respectively. Absorption/stripping process is a conventionally practical process so it is decided to evaluate the separation of methane from hydrogen and carbon monoxide by this process. Since the operating pressures of the absorber and stripper are about 500 psia and 487 psia respectively, the mole fractions of propane in the outlet gas streams of the absorber and stripper are about 6.75 x 10 6 and 1 x 10 4 at -230.8°F and -184°F respectively. 

If carbon monoxide is initially present (case of synthesis gases produced by partial oxidation or steam reforming, for example), a residua] content is inevitable in the purified gas. This can at best be reduced to XS per cent volume, a maximum purity corresponding to the value given by the liquid/vapor equilibria of the H2/CO mixture at the service pressure(3to4.10 Paabsolute),aj atthemaximumcoolingtemperature(S — 155 0. A methane carbon monoxide column can finally be used to separate the CO. 

Liquid propylene, gaseous carbon monoxide and hydrogen, and a soluble cobalt catalyst are fed to a high-pressure catalytic reactor. The reactor effluent goes to a flash tank, where all of the solution constituents are vaporized except the catalyst, which is recycled to the reactor. The reaction products are separated from unconsumed reactants in a multiple-unit process, and the product stream, which contains both butyraldehyde and /i-butanol, is subjected to additional hydrogenation with excess hydrogen, converting all of the butyraldehyde to butanol. 

The passage of ethanol vapors over such an activated copper catalyst at one atmosphere pressure and about 350° C. at such a rate that only 50 per cent is decomposed results in the conversion of about 11 per cent of the reacted alcohol to ester and the rest to aldehyde. However, when a pressure of 270 atmospheres is employed and the ethanol conducted over the catalyst at 350° C. at a rate equal to four volumes of liquid ethanol per volume of catalyst per hour, about 50 per cent of the alcohol is converted per pass, 5 per cent is decomposed to carbon monoxide and methane and 45 per cent passes through unchanged. Of the alcohol converted about half goes to ethyl acetate, a quarter goes to form M-butyl alcohol, and the remainder forms acetic add and acetaldehyde. These products are separated by a process of distillation and the hydrogen recovered as such. 

This type of unit features the main steps encountered in partial condensation. The available gas mixture, previously dried on molecular sieves, is cooled to around — 120 C by heat exchange in a series of piaicexchangers operating in countercurrent flow on the cold purified products, and is then introduced at the bottom of a tray column with a downflow of liquid methane. The operation takes place at a pressure of abont 1.6.10 Pa absolute. It yields hydrogen with a purity better than 98.5 per cent volume, and which contains less than 10 ppm of CO. After expansion and partial vaporization, the extract feeds a distillation colnmn operating at 0.2. 10 Pa absolute, which separates the carbon monoxide at the top with a yield of at least 80 per cent at a purity over 99 per cent volume, and liquid methane at the bottom. This methane provides reflux to the scrubbing column and partly to the feed cooling uuiL... 

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