Propane system

Physica.1 Properties. Carbonyl sulfide [463-58-1] (carbon oxysulfide), COS, is a colorless gas that is odorless when pure however, it has been described as having a foul odor. Physical constants and thermodynamic properties are Hsted ia Table 1 (17,18). The vapor pressure has been fitted to an equation, and a detailed study has been made of the phase equiUbria of the carbonyl sulfide—propane system, which is important ia the purification of propane fuel (19,20). Carbonyl sulfide can be adsorbed on molecular sieves (qv) as a means for removal from propane (21). This approach has been compared to the use of various solvents and reagents (22). 

Figure 11-47. Two-stage propane system for Example 11-4. (Excerpted by special permission Mehra, Y. R. Chemical Engineering, March 26,1979. McGraw-Hill, Inc., New York. All rights reserved.)...

The C—Sn—S angle in this stannathiacyclo- 173 propane system is small (45.7°). 

Fig. 2. RPT regions for a methane-ethane-propane system on 298-K water.

Data are not widely available, but it is likely that liquid propane fuel systems should have improved vehicle acceleration relative to vaporized propane fuel systems. Vaporization of the propane would occur right in the intake port, cooling the intake air and regaining some of the volumetric efficiency loss that fully vaporized propane systems experience. More precise control of propane metering, especially during acceleration, should also improve vehicle acceleration performance. Such propane fuel systems should also have excellent driveability and cold-start performance the same or better than gasoline vehicles. 

The valves used in propane systems must be made from steel, ductile (nodular) iron, malleable iron, or brass. Soft parts of these valves such as gaskets, valve seat disks, packing, seals, and diaphragms must be made of materials that are certified by the manufacturer to be compatible with propane. Valve pressure ratings shall be consistent with the pressures observed in the intended application [3.14]. 

Flanged connections used in propane systems shall have gaskets that are compatible with propane and also have a melting point of greater than 816°C (1500°F) [3.14]. Whenever flanged joints are opened in propane systems, the gasket is to be replaced. 

The materials used in propane dispensers include steel, wrought iron, brass, and aluminum. Dispensing nozzles are made from aluminum, brass, and steel. Few elastomer gaskets are used in propane systems—most are aluminum or steel. Propane dispensing systems should incorporate filters to prevent debris and heavy oils from being pumped into the vehicle fuel tank. 

Trust, D. B. Kurata, F. Vapor-Liquid Phase Behavior of the Hydrogen-Carbon Monoxide-Propane Systems AIChE J. 1971,... 

Figure 2. Phase diagram of an. 4077water/supercritical propane system in the oil-rich comer of the temaiy phase diagram. The regions to the right of the solid lines are the one-phase, clear microemulsions. The various IV value lines ([H2O]/ [AOT]) are also indicated. The temperature of the system is 103°C. (Compositions are given in weight percent.)...

Foldiak and Horvath studied the radiolysis of cyclopropane-propane and cyclopropane-propene mixtures. Horvath and coworkers" reported on the comparison between photolysis and radiolysis of the mixture cyclopropane-propane system. 

Heating divinylcyclopropanes cw-74 in high-boiling solvents also leads to the formation of cycloheptadienes, accompanied in some cases by isomerization of the starting divinylcyclo-propane system. ... 

The propane system shown in Fig. 11.3 is clearly subcritical as the critical temperature of propane is about 96°C. An increase of the C02 fraction ((3) in the mixture of C02 and propane shifts the one-phase region (1), i.e. the bicontinuous microemulsion, to lower temperatures. For pure C02 the bicontinuous microemulsion (1) exists around 35°C, which is higher than the Tc = 31°C of C02. In other words, the C02 solubilised in the microemulsion is supercritical Knowing how to tune the phase behaviour of these systems, one can easily shift phase diagrams on the temperature scale by simply choosing an appropriate surfactant. Other tuning parameters are the oil-to-water fraction and the temperature which maybe adjusted such that, e.g. a C02-in-water droplet microemulsion forms. 

Figure 3.36 The effect of ethanol and acetone cosolvents on the cloud point pressure of the poly(ethylene-co-methyl acrylate) (90mol% ethylene and 10 mol% methyl acrylate)-propane system. The copolymer concentration is fixed at 5 wt% and the weight-average molecular weight of the copolymer is 34,000 with a molecular weight polydispersity of 2.0. This copolymer is —15% crystalline. (Hasch et al., 1993.)...

Figure 5.9 Phase behavior of the acetone-propane system. The symbols represent experimental data (Gomez-Nieto and Thodos, 1978). The solid lines represent calculations with the Sanchez-Lacombe EOS with...

The calculated cloud point curve for the EMAgg/aj-propane system is shown in figure 5.10. The best fit of the experimental data was obtained with kjj = 0.023 and i7,y = -0.002. If kij becomes more positive, the curve shifts to higher pressures if 17,y becomes more positive, the curve shifts to lower pressures. But the shift in the curve and its slope are more sensitive to changes in 17,y than A ,y. 

Figure 5.10 Comparison of calculated (lines) and experimental cloud point data (symbols) of the poly(ethylene-co-methyl acrylate) (69 mol%/ 31 mol%)-acetone-propane system (Hasch et al., 1993). The polymer concentration is fixed at 5wt%. The calculations are performed with the Sanchez-Lacombe EOS with kij and 17,y set equal to zero for the EMAt9/3i-acetone pair, kij = 0.030 and rj/y = 0.000 for the propane-acetone pair, and kij = 0.023 and 77,/ = -0.002 for the EMA soi-propane pair. The weight average and number average molecular weights of EMA69/31 are 58,900 and 31,000, respectively.

Figure 9.5 Effect of molecular weight on the pressure-composition behavior for the high-density polyethylene (1.3% methyl content)-propane system at 110°C.

Some C4 and C5 secondaries have also been observed [256, 266, 271], though in small concentrations, in all high pressure propane systems except the low-energy photon impact system [265], and it appears certain that some of the minor fragments are responsible for the formation of these secondary ions. It is also probable that C3H7 and C3H6 participate in the formation of C4 and C5 secondaries. 

The H2 transfer reaction between C3H6 and CsHg in the propane system, described in Section 6.1.3, constitutes a similar case in the complementary process. On the other hand, no H or H2 transfer occurs when cyclopropane ions are impacted on cyclohexane, benzene or cyclobutane. 

Figure 17.9, Feed system for separation of propylene-propane system by distillation at lOOpsia.

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