Separation processes classification

The energy or power required by any separation process is related more or less directly to its thermodynamic classification. There are, broadly speaking, three general types of continuous separation processes reversible, partially reversible, and irreversible. 

Table 16.1. Classification of membrane separation processes for liquid systems...

Industrial membrane processes may be classified according to the size range of materials that they are to separate and the driving force used in separation. There is always a degree of arbitrariness about such classifications, and the distinctions that are typically drawn. Table 16.1 presents classification of membrane separation processes for liquid systems. 

It will be recalled from the earlier section that classification is one of the sizing separation processes, the other being screening. The two differ in that while screening does not take... 

Ion separation systems can be classified as static ion separation systems and dynamic ion separation systems .1,2 The proposed classification is related to the time dependence of the mass spectrometric ion separation systems during the separation process of the ions. 

As described above, various separation processes and CFCs have been developed and proposed, aiming at the modification of the current PUREX process and reformation of the Improved PUREX and also aiming at the establishment of advanced reprocessing processes. Figure 1.10 shows a classification scheme for these processes and CFCs. 

FIGURE 1.10 Classification scheme of separation processes developed and proposed for the reprocessing or partitioning. 

Because there are many different ways to combine a catalyst with a membrane, there are numerous possible classifications of the CMRs. However, one of the most useful classifications is based on the role of the membrane in the catalytic process we have a catalytically active membrane if the membrane has itself catalytic properties (the membrane is functionalized with a catalyst inside or on the surface, or the material used to prepare the membrane is intrinsically catalytic) otherwise if the only function of the membrane is a separation process (retention of the catalyst in reactor and/or removal of products and/or dosing of reagents) we have a catalytically passive membrane. The process carried out with the second type of membrane is also known as membrane-assisted catalysis (a complete description of the different CMRs configurations will be presented in a specific chapter). 

Table 4.4. Classification of singular points in reactive distillation and reactive membrane separation processes.

We found earlier that a theoretical consideration of displacement and transport exerts a unifying influence on separation science, bringing diverse methods under a common descriptive umbrella. The theory leads in a natural way to the formation of categories of separations which can be considered the beginning of a fundamental classificatory system. Here we generalize the results of transport theory to develop a fundamental basis for classification. While the resulting scheme will not be a complete polythetic classification, it will be based upon some of the most fundamental features of the separation process. These basic features, incorporated in the classification, should correlate well with other properties of separations in the same way that the number of outer-shell electrons is directly related to the diverse properties of the elements of the periodic table. This transport-oriented... 

IH TABLE I Classification of Separation Processes on the Basis of Physical - Chemical Characteristics... 

Adsorption/separation processes are based on adsorption isotherms (thermodynamics) and intracrystalline diffusivity (kinetics). Figure 16.1 illustrates various shapes of adsorption isotherms depending on the VOC nature, trichloroethylene (TCE) and tetrachloroethylene (PCE), and of the zeolite, MFI with Si/Al > 500 and FAU (Si/Al > 100) (14). The isotherms of VOCs adsorbed on FAU present a more or less S-shape which corresponds to type V of the IUPAC classification. In contrast, the isotherms of VOCs on MFI are more of type I, with the additional particularity of a step at 4 molecules per u.c. for PCE adsorption. The... 

In this chapter, we will introduce fundamental concepts of the membrane and membrane-separation processes, such as membrane definition, membrane classification, membrane formation, module configuration, transport mechanism, system design, and cost evaluation. Four widely used membrane separation processes in water and wastewater treatment, namely, microfiltration (MF), ultrafiltration (UF), nanofiltrafion (NF), and reverse osmosis (RO), will be discussed in detail. The issue of membrane foufing together with its solutions will be addressed. Several examples will be given to illustrate the processes. 

In complex systems where the number of groups to be separated during classification becomes larger, the performance of simple unsupervised methods (Section 3) degrades, requiring the use of more sophisticated supervised chemometric techniques. Additionally, in fields such a process NMR where there is a need for quantifying a component, the use of supervised methods becomes necessary. The different supervised methods described in the sections below have all been utilized in the chemometric analysis of NMR data for classification and/or quantitation. Examples utilizing these different techniques are discussed in Section 5. 

The literature of the commercial development of hydrocarbons derivable from petroleum and natural gas is meager until about 1935. Since 1945, the literature has become extensive. This study includes the paraffins, olefins, alicyclics, aromatics, acetylene, and separation processes. Journals and sections of journals of value are discussed. The main subject heads to be consulted in Chemical Abstracts are given. There is considerable overlapping of subject matter in the U. S. patent classification system pertinent classes are listed. References in the bibliography were selected to show the various types available. 

The objective of this chapter is to provide comprehensive knowledge-based information by critical analysis, classification, model description, and applications of a variety of ELM separation processes. New perspectives and directions of development in these fields are also discussed. 

IAs are classified by several groupings. If the antigen-antibody complex is separated from the unbound reactants before quantitation, it is referred to as a heterogeneous assay. For homogeneous assays, the detection of the bound complexes can be differentiated from the unbound reactants, and no separation process is needed. Another classification is competitive and noncompetitive IA. The measure of occupied or unoccupied Ab determines whether an IA is competitive or noncompetitive, not whether the label is on the Ag or Ab. A broader classification is limited-reagent assay and excess-reagent assay (7,8). They will be discussed in more detail. 

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