Benzene Antoine vapor pressure

Calculate the vapor pressure of benzene at 50°C using the Antoine Equation. Also estimate the normal boiling point of benzene (the vapor pressure at 1 atm), and compare it with the experimental value (taken from a handbook). 

However, this pressure does not represent the final system pressure, since benzene will exert a vapor pressure at 298 K. Benzene s vapor pressure can be determined by the Antoine equation. Looking up the Antoine coefficients in Table A.l yields ... 

The system l-chlorobutane(l)/benzene(2)/chlorobenzene(3) conforms closely to Raoult s la The vapor pressures of the pure species are given by the following Antoine equations ... 

The vapor pressure of benzene can be calculated from the Antoine equation. 

One way to obtain the necessary vapor-pressure data for benzene and toluene is to employ the Antoine equation ... 

The vapor pressures of benzene and toluene at 80°C are determined from the Antoine equation to be 757.7 mm Hg and 291.2 mm Hg, respectively. Assuming that nitrogen is insoluble in the condensate. Equation 6.4-8 gives... 

Assume that the vapor pressures of benzene and toluene are given by the Antoine equation. Table 6.1-1 that Raoult s law—Equation 6.4-1—applies and that the enthalpies of benzene and toluene liquid and vapor are linear functions of temperature. Specific enthalpies at two temperatures are given here for each substance in each phase. 

You have been assigned to simulate a flash evaporator that separates a liquid feed stream containing benzene and toluene at temperature Tf ( C) into liquid and vapor product streams m equilibrium at temperature T( C) and pressure P mm Hg). The compositions of the product streams are related by Raoulfs law (Equation 6.4-1), and the component vapor pressures are expressed by the Antoine equation (Table B.4). 

A mixture of three components (60% benzene, 30% toluene and 10% ethylbenzene) is separated in a DWG with sieve plates and lateral downcomers. The vapor pressures Ry of components were calculated on the basis of Antoine equation, and the trays efficiency was set at value 1 (equilibrium trays). 

The separation of benzene (1) and cyclohexane (2) by distillation is complicated due to the formation of an azeotrope (Example 2.5). Vapor-liquid equilibrium data for this binary are required for the design of a workable separation process. As a first step, find the azeotropic composition and temperature at 100 kPa pressure. Use the van Laar equation for activity coefficients with parameters A12 = 0.147, A21 = 0.165. The computations can be made with assumptions consistent with low pressure conditions. The vapor pressures of benzene and cyclohexane can be represented by the Antoine Equation 2.19 with the following constants Al = 13.88, Bl = 2788.5, Q = -52.36, A2 = 13.74, = 2766.6,... 

To determine the overall effect on pressure error of normally distributed variation in temperature, the Antoine equation must be employed. Thus, the pressure error is a function of the compound of interest. To focus on typical situations, three compounds representative of the range of application of the isoteniscope were used. These were benzene with a relatively high vapor pressure ("true value" = 95 torr at 25°C) toluene for a medium vapor pressure ("true value" = 28 torr at 25°C) and chlorobenzene for a low vapor pressure ("true value" = 12 torr at 25°C). 

The physical-property data in the preceding equation will correspond to the average film conditions. The inner edge of the film is a saturated mixture of benzene vapors and nitrogen at 300 K and 1 bar, while the outer edge is virtually pure nitrogen at the same temperature and pressure. The vapor pressure of benzene, PA, at 300 K is from the Antoine equation (Himmelblau, 1989)... 

Raoult s law may be used to determine phase compositions for the binary system benzene-toluene, at low temperatures and pressures. Determine the composition of the vapor in equilibrium with a liquid containing 0.4 mole fraction of benzene at 300 K, and calculate the total equilibrium pressure. Estimate the vapor pressure of benzene and toluene at 300 K from the Antoine equation,... 

An equimolal solution of benzene and toluene is totally evaporated at a constant temperature of 90°C. What are the pressures at the beginning and the end of the vaporization process Assume an ideal solution and use the Antoine equation with constants from Appendix I for vapor pressures. 

Three moles of benzene, four moles of acetonitrile, and four moles of water are placed in a closed vessel and brought into VLLE at 333 K, 0.70 bar. Assume the liquid phases obey the NRTL equations (Appendix J), with parameter values given in Table J.l. Appendix D contains Antoine parameters for vapor pressures of the pure-components. Use the double Rachford-Rice algorithm of Figure 11.6 to determine the following ... 

We start by computing the vapor pressure at the maximum temperature of 30dC using the Antoine constants for benzene listed in Table 6.1. Thus,... 

The vapor pressure of either benzene or toluene is given by Antoine s eguation as a function of temperature as in the following eguations ... 

Here we calculate the vapor pressures of benzene and toluene at 20°C using the Antoine equation (see Chapter 5) and Table A.2. For benzene... 

A liquid mixture of benzene and toluene containing 50.0 wt% benzene at 90 C and pressure Po is fed at a rale of 32.5 m /h into a flash evaporator, a heated tank maintained at a pressure P,ank Po-When the feed is exposed to the reduced pressure in this unit, a portion of it evaporates. The liquid and vapor product streams are in equilibrium at 75 C and P,ank- liquid product contains 43.9 mole% benzene. When carrying out the requested calculations, assume volume additivity of liquid benzene and toluene, use Raoult s law and the Antoine equation where necessary, and neglect the effect of pressure on enthalpy. 

Hermsen and Prausnitz (1963) present the P-Xj data for the system benzene(l)-cyclopentane(2) at 25°C shown in Table 13.E.11. Calculate the values of the vapor phase composition assuming, because of the low pressures involved and the similarity of the two components, ideal vapor behavior. The following Antoine constants are given ... 

Using the Peng-Robinson equation of state, calculate the saturation pressure of pure benzene at 400 K using fugacity coefficients to calculate the fugacity for both vapor and liquid phases. Compare the results with the values of obtained by the Antoine equation and report the percent error. 

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