Four-component mixtures separability

Take two different sequences for the separation of a four-component mixture" (Fig. 5.7). Summing the feed flow rates of the key components to each column in the sequence, the total flow rate is the same in both cases ... 

Figure 5.7 Two possible configurations of simple columns for the separation of a four-component mixture. (From Smith and Linnhoff, Trans. IChemE, ChERD, 66 195, 1988 reproduced by permission of the Institution of Chemical Engineers.)...

Figure 18. Vacancy Chromatograms for the Separation of a Four Component Mixture...

Figure 7.41 Microcolumn size-exclusion separation of a four-component mixture using THF as the mobile phase and UV detection at 230 nm. Legend (1) Irganox 1010 (2) oleamide (3) AO 2246 (4) Cyasorb UV9 (5) sample solvent (CHCI3). After Fujimoto et al. [931], Reprinted from Journal of Chromatography, 438, C. Fujimoto et al., 329-337, Copyright (1988), with permission from Elsevier...

A distillation column separating 150 kmol-h 1 of a four-component mixture is estimated to have a minimum reflux... 

Table 11.9 shows the composition of a four-component mixture to be separated by distillation. The K-values for each component at the bubble point temperature of this mixture are given. The liquid- and vapor-phase mixtures of these... 

Table 11.9 Data for four-component mixture to be separated.

Vapor flowrate in kmoMr1 for each task for the separation of a four-component mixture are ... 

The mathematical development of estimating correlation is taken from Liu s work and is a simple treatment. In 2DLC, we can form a retention matrix composed of the scaled k values for each zone so that each dimension (i.e., each unique column) has a k row vector for the compounds that were separated on it. In two dimensions, the retention representation becomes a matrix, ft, so that k takes the form for a four-component mixture ... 

In the fractionation of multicomponent mixtures, the essential requirement is often the separation of two components. Such components are called the key components and by concentrating attention on these it is possible to simplify the handling of complex mixtures. If a four-component mixture A-B-C-D, in which A is the most volatile and D the least volatile, is to be separated as shown in Table 11.3, then B is the lightest component appearing in the bottoms and is termed the light key component. C is the... 

Table 3.12 Sequences for separating four-component mixture by simple columns.

Rgure 10 Schemes for complete separation of four-component mixtures after removal of (a) more strongly and (b) less strongly sorbed components. 

Fig. 1.24. Overlapping resolution map for the separation of a four-component mixture with optimisation of tw

Assuming a four component mixture and simple two product splits. Fig. 1 shows all possible separation sequences into the pure components under the assumption of sharp splits. If the number of components is increased, an exponential growth of the number of sequences is observed (Fig. 2, sequences). This behaviour is well known [6] and can be described by... 

A depropanizer is a distillation operation encountered in almost all oil refineries. Our task here is to design a column to separate 1000 mol/s of a four component mixture containing 300 mol/s n-propane and 500 mol/s -butane so that there is no more than 3.5 mol/s of n-propane present in the bottom product and no more than 3.5 mol/s of n-butane is... 

It is proposed to design a distillation column for coarse separation of a four-component mixture between components 2 and 3. (The components are numbered by decreasing volatility). The combined mole fraction of components 1 and 2 in the distillate should be 0.65, and the ratio of the mole fraction of components 3 and 4 in the bottoms should be... 

Two columns are needed in either of these sequences the first to recover one of the components in the ternary and the second to separate the remaining two. For a four-component mixture, five altemative sequences could be used, each requiring three distillation columns ... 

Systems containing dimethylsulfoxide, methanol and hydtodiloric add have been studied for the anion-exchange behavior of 26 elements [33]. Numerous separations of two- to four-component mixtures of metal ions were carried out with quantitative results. 

In the rectification tower, four equations are available from material balances (overall and component material balances) for the separation of the four components. If the feed or input amount and its composition are known, then one has two unknown streams H (head product) and B (bottom product) and three unknown concentrations in each stream. Thus, generally there are eight unknown values for a four component mixture. Only two of these unknown values are to be determined. Thus the material balance of the rectification tower can be evaluated to obtain the top and bottom product rates. The vapor stream in the stripping section can be determined as the vapor stream ascending from the tower bottom. This stream can be taken as constant throughout the stripping section of the tower. This vapor stream plus the fraction of feed that is vapor will yield both the head product stream as well as the reflux stream that will be returned to the tower. The reflux ratio can be determined based on the minimum reflux. There is a method for the evaluation of the minimum reflux. This method will be shown in a later section. 

When [he feed mixture contains more than two components, (he separation is generally leimed multicomponent, even (hough a three-component mixture Is also known as a ternary. a four-component mixture as a qnertemary, and so on. The key point is that when (here ate more than two components, (he simple procedures such as McCabe- Thiele cannot be used with reliability and it is necessaty to use analytical rather than graphical approaches. However, the same principles are used, and die MESH equations are applied at each theoretical stage. 

Fig. 2.3.2-24 General separation scheme for splitting a four-component mixture (a) and development of a thermodynamically optimal separation scheme (a ) [Kaibel 1989a],...

The components of mixtures can be easily collected from the effluent of a liquid chromatograph and analyzed by NMR and IR spectroscopies. As an example, a sample of S1132 was Injected repetitively and the four components collected separately. The small amounts obtained are quite suitable for infrared samples. New Fourier Transform NMR spectrometers equipped with micro sized probes are now available for small samples. The and... 

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