# Negisht

Next, and more difficult, is the calculation of the true mole fraction This calculation is achieved by simultaneous [c.34]

Sinor, 1960 (2) Conti, 1960 (3) Pratt, 1947 (4) Scatchard, 1952 (5) Steinhauser, 1949 (6) Abbott, 1975 (7) Severns, 1955 (8) Nagata, 1962. [c.54]

In the next three sections we discuss calculation of liquid-liquid equilibria (LLE) for ternary systems and then conclude the chapter with a discussion of LLE for systems containing more than three components. [c.63]

Unfortunately, good binary data are often not available, and no model, including the modified UNIQUAC equation, is entirely adequate. Therefore, we require a calculation method which allows utilization of some ternary data in the parameter estimation such that the ternary system is well represented. A method toward that end is described in the next section. [c.66]

Nagata, I., Hayashida, H., J. Chem. Eng. Japan, 3, 161 (1970). [c.80]

Equations (7-8) and (7-9) are then used to calculate the compositions, which are normalized and used in the thermodynamic subroutines to find new equilibrium ratios,. These values are then used in the next Newton-Raphson iteration. The iterative process continues until the magnitude of the objective function 1g is less than a convergence criterion, e. If initial estimates of x, y, and a are not provided externally (for instance from previous calculations of the same separation under slightly different conditions), they are taken to be [c.121]

Again, Equations (7-8) and (7-9) are then used to calculate new compositions. These compositions, normalized, and the new value for T are utilized in thermodynamic subroutine calls to find equilibrium ratios and enthalpies for use in the next iteration. [c.121]

These initial estimates are used in the iteration function. Equation (37), to obtain values of the 2 s that do not change significantly from one iteration to the next. These true mole fractions, with Equation (3-13), yield the desired fugacity [c.135]

METHYL ACETATE VL 16 323 121.17 -187.87 3.66 NAGATA. 1970 [c.192]

ETHYL ACETATE VL 20 335-3A7 - 10 7.SA 579.61 16.97 NAGATA,19628 [c.197]

METHYL ACETATE VL 13 318 -81.84 502.74 8. 72 NAGATA,1972 [c.197]

METHYL ACETATE VL lA 308 -83.96 508.39 3. 72 NAGATA,1972 [c.197]

NAGATA,I /J CHEM.ENG DATA 7,367(19620) [c.205]

NAGATA,I, OHTA,T, TAKAHASHI,T /J CHEM ENG JAPAN 5(3), [c.205]

This value determines the amount the step-size is reduced to satisfy the criteria of a SSQ which decreases from one iteration to the next. The amount of the decrease is equal to the previous value of the step-limiting parameter divided by RP. [c.223]

B. The next four data cards contain pure-component data for component one. [c.224]

C. The next four data cards contain pure-component data for component two. The same format as used in part B is repeated here. [c.225]

D. The next card supplies the solvation and association parameters, and the third parameter for either the UNIQUAC, NRTL, or Wilson equation, if this parameter is not being fitted. [c.225]

E. The next data card contains information about the binary VLE data. FORMAT(2A3, 4X, 2A3, 4X, 12, 18X, 5(I1,1X)). [c.225]

I. The next card gives the initial parameter estimates. [c.227]

DA Change in the vapor-feed ratio from one iteration to the next [c.321]

DT Change in the temperature from one iteration to the next. [c.321]

PROCEED TO NEXT ITERATION 270 A=AN T = TN SL=1 [c.325]

Next to last iterative value of extract-feed ratio. [c.335]

Change in extract-feed ratio from one iteration to the next. Partial derivative of Rachford-Rice objective function with respect to extract-feed ratio. [c.335]

PARIN first loads all pure component data by reading two records per component. The total number of components, M, in the library or data deck must be known beforehand. Next the associ-ation/solvation parameters are input for M components. Finally all the established UNIQUAC binary interaction parameters (or noncondensable-condensable interaction parameters) are read. [c.341]

The next requirement is to achieve the initial setting for the [c.27]

Stirred-tank reactors become unfavorable if the reaction must take place at high pressure. Under high-pressure conditions, a small-diameter cylinder requires a thinner wall than a large-diameter cylinder. Under high-pressure conditions, use of a tubular reactor is preferred, as described in the next section, although mixing problems with heterogeneous reactions and other factors may prevent this. Another important factor to the disadvantage of the continuous stirred-tank reactor is that for a given conversion it requires a large inventory of material relative to, say, a tubular reactor. This is not desirable for safety reasons if the reactants or products are particularly hazardous. [c.53]

Forward-feed operation is shown in Fig. 3.12a. The fresh feed is added to the first stage and fiows to the next stage in the same direction as the vapor flow. The boiling temperature decreases from stage to stage, and this arrangement is thus used when the [c.85]

To illustrate, UNIQUAC parameters were obtained for the ethanol/cyclohexane system using the extensive isothermal data of Scatchard and Satkiewicz (1964). Figure 2 shows parameters for 5, 35, and 60°C along with the confidence ellipses. These regions indicate that it is possible to choose a single value of 322 appropriate for all temperatures a single value of a2 (e.g. 1300) can be included in all three confidence ellipses, implying that in the range 5-65 C parameter a2 is temperature independent. For 3., however, there is no single value which can intercept all three confidence ellipses. Therefore, parameter a 2 must be represented by a function of temperature as shown in Table 1 where the estimated variance of the fit, a, provides a measure of how well the data are represented. The first line shows results obtained when fitting two UNIQUAC parameters, a 2 21 ii ispendent of temperature. The next two [c.45]

Predictions for the other isobaric systems (experimental data of Sinor, Steinhauser, and Nagata) show good agreement. Excellent agreement is obtained for the system carbon tetrachlor-ide-methanol-benzene, where the binary data are of superior quality. [c.55]

F. The next card supplies the VLB data reference (2 cards if IRF=1). FORMAT(15A4). [c.226]

G. The next NN cards supply the VLB data. NN equals the number of experimental points. Bach card has one set of data. FORMAT(8F10.2). [c.226]

H. The next cards provide estimates of the standard deviations of the experimental data. At least one card is needed with non-zero values. Units are the same as those of the VLE data. FORMAT(4f10.2,I2). [c.227]

The design problem is next formulated as a mathematical problem with design equations and design variables. The design equations are the modeling equations of the units and their specification constraints. Design variables are of two types. The first t3qje of design variables describe the operation of each unit (flow rate, composition, temperature, and pressure), its size (volume, heat transfer area, etc.), as well as the costs or profits associated with the units. Since [c.9]

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**Negisht**:

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Organic syntheses based on name reactions and unnamed reactions (1994) -- [ c.222 ]