Phase diagrams supercritical fluid region

Figure 5.1 Phase diagram showing supercritical fluid region...

Figure 2 A schematic of a phase diagram for water showing solid, liquid and gas phases relative to the supercritical fluid region.

FIGURE 24.1 Definition of the supercritical fluid region in the phase diagram of a pure substance. 

Saeki, S. (1997) Calculation of the phase diagram of polymer solution over supercritical fluid region based on the Patterson-Delmas theory of corresponding state. Fluid Phase Equilib. 136,87-92. 

Figure 14.13 The pressure temperature phase diagram of a pure substance, emphasizing the supercritical fluid region. The critical point is the highest pressure and temperature at which a pure substance can exist in a vapor iquid equilibrium.

Figure 11.2 Cartxin dioxide pressure-temperature phase diagram. In the supercritical fluid region, the COj becomes denser than gas and can approach the density of the liquid CO. At the higher densities, the solubility of the CO increases significantly as well.

Chapter 14 describes the phase behavior of binary mixtures. It begins with a discussion of (vapor -l- liquid) phase equilibria, followed by a description of (liquid + liquid) phase equilibria. (Fluid + fluid) phase equilibria extends this description into the supercritical region, where the five fundamental types of (fluid + fluid) phase diagrams are described. Examples of (solid + liquid) phase diagrams are presented that demonstrate the wide variety of systems that are observed. Of interest is the combination of (liquid + liquid) and (solid 4- liquid) equilibria into a single phase diagram, where a quadruple point is described. 

There is a region in a gas-liquid phase diagram where a substance can exist with properties characteristic of both the gas and liquid states. This state is referred to as fluid, or more precisely, a supercritical fluid, since it exists in the region beyond the critical points for the substance. Visualize a transparent container half filled with liquid and sealed. As its temperature is increased its pressure will increase until the critical point... 

Figure 4.1 Single-component phase diagram highlighting the supercritical fluid (SCF) region and the critical point.

Figure 8.22 shows ternary TMB-methanol-methane data at 35°C and 152 bar, conditions very similar to those used in the screening study. Several features of this diagram indicate that methane is the supercritical fluid solvent of choice for the separation of TMB from methanol. The shape of the two-phase region and the slopes of the tie lines reveal that greater than 70 wt%... 

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