Water residue curve maps

Fig. 5. The acetone—2-propanol—water system where I represents the 2-propanol—water azeotrope, (a) Residue curve map (34) (b) material balance lines...

Fig. 11. Separation of nitric acid, HNO, and water, H2O, using sulfuric acid, H2SO4, as the solvent, (a) Residue curve map and material balance lines where...

Fig. 16. Residue curve map calculated for the ethanol—water—benzene mixture where A is the end poiat of the vapor line I represents a homogeneous...

Podebush Sequence forPthanol—Water Separation. When ethyl acetate is used as the entrainer to break the ethanol—water azeotrope the residue curve map is similar to the one shown in Figure 21d, ie, the ternary azeotrope is homogeneous. Otherwise the map is the same as for ethanol—water—benzene. In such... 

More Complex Mixtures. AH the sequences discussed are type I Hquid systems, ie, mixtures in which only one of the binary pairs shows Hquid—Hquid behavior. Many mixtures of commercial interest display Hquid—Hquid behavior in two of the binary pairs (type II systems), eg, secondary butyl alcohol—water—di-secondary butyl ether (SBA—water—DSBE), and water—formic acid—xylene (92). Sequences for these separations can be devised on the basis of residue curve maps. The SBA—water—DSBE separation is practiced by ARGO and is considered in detail in the Hterature (4,5,105,126). 

FIG. 13-58 (Continued) Residue curve maps, (h) MEK-MIPK-water system containing two minumum-hoiling binary azeotropes. 

FIG. 13-73 Residue curve maps for acetone-methanol systems, (a) With water, (h) With MIPK. 

The transformed variables describe the system composition with or without reaction and sum to unity as do Xi and yi. The condition for azeotropy becomes X, = Y,. Barbosa and Doherty have shown that phase and distillation diagrams constructed using the transformed composition coordinates have the same properties as phase and distillation region diagrams for nonreactive systems and similarly can be used to assist in design feasibility and operability studies [Chem Eng Sci, 43, 529, 1523, and 2377 (1988a,b,c)]. A residue curve map in transformed coordinates for the reactive system methanol-acetic acid-methyl acetate-water is shown in Fig. 13-76. Note that the nonreactive azeotrope between water and methyl acetate has disappeared, while the methyl acetate-methanol azeotrope remains intact. Only... 

FIG. 13-76 Residue curve map for the reactive system methanol-acetic acid-methyl acetate-water in chemical eqiiihhriiim. 

Nitromethane shows the simplest residue curve map with one unstable curved separatrix dividing the triangle in two basic distillation regions. Methanol and acetonitrile give rise two binary azeotropic mixtures and three distillation regions that are bounded by two unstable curved separatrices. Water shows the most complicated residue curve maps, due to the presence of a ternary azeotrope and a miscibility gap with both the n-hexane and the ethyl acetate component. In all four cases, the heteroazeotrope (binary or ternary) has the lowest boiling temperature of the system. As it can be seen in Table 3, all entrainers except water provide the n-hexane-rich phase Zw as distillate product with a purity better than 0.91. Water is not a desirable entrainer because of the existence of ternary azeotrope whose n-hexane-rich phase has a water purity much lower (0.70). Considering in Table 3 the split... 

Residue curve maps of the THF system were predicted for reactive distillation at different reaction conditions (Fig. 4.29). The topology of the map at nonreactive conditions (Da = 0) is structured by a binary azeotrope (unstable node) between water and THF. Pure water and pure THF are saddle nodes, while the 1,4-BD vertex is a stable node. 

Fig. 4.30. Residue curve maps for reactive membrane separation 1,4-BD — THF + Water p= 5 atm Knudsen-membrane. (a) Da = 0 (b)...

Figure 3.9 Sketch of a residue curve map isopropanol, n-propanol, water.

Figure 8.4 presents the residue curve map of simultaneous phase and chemical equilibrium at normal pressure. Special coordinates, Xx (acid + water) and X2 (acid + ester) enable tbe representation of all four components in a bidimensional... 

Figu re 8.4 Residue curve map of the reactive mixture lauric acid/2-ethylhexanol/water/2-ethylhexyl dodecanoate a = initial estimation b = experimental data [2],... 

In the following, the strategy presented before will this time be applied for developing a process for the esterification of lauric acid with methanol. All the thermodynamic data for pure components and binary mixtures are available in Aspen Plus. A residue curve map of the reactive mixture at equilibrium can be computed as described in Appendix A. A useful representation can be done in reduced coordinates defined by Xx = water + add and X2 = add + ester. The diagram displayed... 

Figure 10.1 Residue curve map of the mixture vinyl acetate/acetic acid/water.

Figure 6.1 Residue curve map for vinyl acetate, water, and acetic acid.

FIG. 13-78b Residue curve map MEK-MIPK-water system at 1 atm containing two minumum-boiling binary azeotropes. 

FIG. 13-78C Residue curve map Ethanol-cyclohexane-water system at 1 atm containing four minimum-boiling azeotropes (three binary and one ternary) and three distillation regions. 

FIG. 13-96 Residue curve maps for the reactive system methanol—acetic aci(d-methyl acetate-water in phase and chemical equilibrium at 1-atm pressure, a) Calculated by Barbosa and Doherty [Chem. Eng. Sci., 43,1523 (1988)]. (b) Measured by Song et al. [Ind. Eng. Chem. Res., 37,1917 (1998)]. 

FIG. 13-130 Residue curve map and batch rectifier paths for methanol, methyl propionate, and water. 

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